The volume of air inspired or expired during each normal, quiet respiratory cycle. Common abbreviations are TV or V with subscript T.
Any method of artificial breathing that employs mechanical or non-mechanical means to force the air into and out of the lungs. Artificial respiration or ventilation is used in individuals who have stopped breathing or have RESPIRATORY INSUFFICIENCY to increase their intake of oxygen (O2) and excretion of carbon dioxide (CO2).
The physical or mechanical action of the LUNGS; DIAPHRAGM; RIBS; and CHEST WALL during respiration. It includes airflow, lung volume, neural and reflex controls, mechanoreceptors, breathing patterns, etc.
The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (= OXYGEN CONSUMPTION) or cell respiration (= CELL RESPIRATION).
Mechanical devices used to produce or assist pulmonary ventilation.
A method of mechanical ventilation in which pressure is maintained to increase the volume of gas remaining in the lungs at the end of expiration, thus reducing the shunting of blood through the lungs and improving gas exchange.
The total volume of gas inspired or expired per unit of time, usually measured in liters per minute.
The capability of the LUNGS to distend under pressure as measured by pulmonary volume change per unit pressure change. While not a complete description of the pressure-volume properties of the lung, it is nevertheless useful in practice as a measure of the comparative stiffness of the lung. (From Best & Taylor's Physiological Basis of Medical Practice, 12th ed, p562)
Lung damage that is caused by the adverse effects of PULMONARY VENTILATOR usage. The high frequency and tidal volumes produced by a mechanical ventilator can cause alveolar disruption and PULMONARY EDEMA.
That part of the RESPIRATORY TRACT or the air within the respiratory tract that does not exchange OXYGEN and CARBON DIOXIDE with pulmonary capillary blood.
Measurement of the amount of air that the lungs may contain at various points in the respiratory cycle.
A syndrome characterized by progressive life-threatening RESPIRATORY INSUFFICIENCY in the absence of known LUNG DISEASES, usually following a systemic insult such as surgery or major TRAUMA.
A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.
Volume of circulating BLOOD. It is the sum of the PLASMA VOLUME and ERYTHROCYTE VOLUME.
The force per unit area that the air exerts on any surface in contact with it. Primarily used for articles pertaining to air pressure within a closed environment.
The exchange of OXYGEN and CARBON DIOXIDE between alveolar air and pulmonary capillary blood that occurs across the BLOOD-AIR BARRIER.
The number of times an organism breathes with the lungs (RESPIRATION) per unit time, usually per minute.
Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.
A clinical manifestation of abnormal increase in the amount of carbon dioxide in arterial blood.
The act of BREATHING in.
Injury following pressure changes; includes injury to the eustachian tube, ear drum, lung and stomach.
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
Damage to any compartment of the lung caused by physical, chemical, or biological agents which characteristically elicit inflammatory reaction. These inflammatory reactions can either be acute and dominated by NEUTROPHILS, or chronic and dominated by LYMPHOCYTES and MACROPHAGES.
RESPIRATORY MUSCLE contraction during INHALATION. The work is accomplished in three phases: LUNG COMPLIANCE work, that required to expand the LUNGS against its elastic forces; tissue resistance work, that required to overcome the viscosity of the lung and chest wall structures; and AIRWAY RESISTANCE work, that required to overcome airway resistance during the movement of air into the lungs. Work of breathing does not refer to expiration, which is entirely a passive process caused by elastic recoil of the lung and chest cage. (Guyton, Textbook of Medical Physiology, 8th ed, p406)
Measurement of the various processes involved in the act of respiration: inspiration, expiration, oxygen and carbon dioxide exchange, lung volume and compliance, etc.
The volume of air remaining in the LUNGS at the end of a normal, quiet expiration. It is the sum of the RESIDUAL VOLUME and the EXPIRATORY RESERVE VOLUME. Common abbreviation is FRC.
Measurement of oxygen and carbon dioxide in the blood.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
Recording of change in the size of a part as modified by the circulation in it.
Measurement of the volume of gas in the lungs, including that which is trapped in poorly communicating air spaces. It is of particular use in chronic obstructive pulmonary disease and emphysema. (Segen, Dictionary of Modern Medicine, 1992)
These include the muscles of the DIAPHRAGM and the INTERCOSTAL MUSCLES.
A pulmonary ventilation rate faster than is metabolically necessary for the exchange of gases. It is the result of an increased frequency of breathing, an increased tidal volume, or a combination of both. It causes an excess intake of oxygen and the blowing off of carbon dioxide.
A condition of lung damage that is characterized by bilateral pulmonary infiltrates (PULMONARY EDEMA) rich in NEUTROPHILS, and in the absence of clinical HEART FAILURE. This can represent a spectrum of pulmonary lesions, endothelial and epithelial, due to numerous factors (physical, chemical, or biological).
The musculofibrous partition that separates the THORACIC CAVITY from the ABDOMINAL CAVITY. Contraction of the diaphragm increases the volume of the thoracic cavity aiding INHALATION.
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Physiological processes and properties of the RESPIRATORY SYSTEM as a whole or of any of its parts.
The pressure that would be exerted by one component of a mixture of gases if it were present alone in a container. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A procedure involving placement of a tube into the trachea through the mouth or nose in order to provide a patient with oxygen and anesthesia.
Ventilatory support system using frequencies from 60-900 cycles/min or more. Three types of systems have been distinguished on the basis of rates, volumes, and the system used. They are high frequency positive-pressure ventilation (HFPPV); HIGH-FREQUENCY JET VENTILATION; (HFJV); and high-frequency oscillation (HFO).
Failure to adequately provide oxygen to cells of the body and to remove excess carbon dioxide from them. (Stedman, 25th ed)
Continuous recording of the carbon dioxide content of expired air.
Techniques for effecting the transition of the respiratory-failure patient from mechanical ventilation to spontaneous ventilation, while meeting the criteria that tidal volume be above a given threshold (greater than 5 ml/kg), respiratory frequency be below a given count (less than 30 breaths/min), and oxygen partial pressure be above a given threshold (PaO2 greater than 50mm Hg). Weaning studies focus on finding methods to monitor and predict the outcome of mechanical ventilator weaning as well as finding ventilatory support techniques which will facilitate successful weaning. Present methods include intermittent mandatory ventilation, intermittent positive pressure ventilation, and mandatory minute volume ventilation.
The amount of BLOOD pumped out of the HEART per beat, not to be confused with cardiac output (volume/time). It is calculated as the difference between the end-diastolic volume and the end-systolic volume.
Stretch receptors found in the bronchi and bronchioles. Pulmonary stretch receptors are sensors for a reflex which stops inspiration. In humans, the reflex is protective and is probably not activated during normal respiration.
The upper part of the trunk between the NECK and the ABDOMEN. It contains the chief organs of the circulatory and respiratory systems. (From Stedman, 25th ed)
Volume of PLASMA in the circulation. It is usually measured by INDICATOR DILUTION TECHNIQUES.
Small polyhedral outpouchings along the walls of the alveolar sacs, alveolar ducts and terminal bronchioles through the walls of which gas exchange between alveolar air and pulmonary capillary blood takes place.
The maximum volume of air that can be inspired after reaching the end of a normal, quiet expiration. It is the sum of the TIDAL VOLUME and the INSPIRATORY RESERVE VOLUME. Common abbreviation is IC.
A transient absence of spontaneous respiration.
Measure of the maximum amount of air that can be expelled in a given number of seconds during a FORCED VITAL CAPACITY determination . It is usually given as FEV followed by a subscript indicating the number of seconds over which the measurement is made, although it is sometimes given as a percentage of forced vital capacity.
Pathological processes involving any part of the LUNG.
Methods of creating machines and devices.
Measurement of volume of air inhaled or exhaled by the lung.
The interruption or removal of any part of the vagus (10th cranial) nerve. Vagotomy may be performed for research or for therapeutic purposes.
Recording changes in electrical impedance between electrodes placed on opposite sides of a part of the body, as a measure of volume changes in the path of the current. (Stedman, 25th ed)
A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.
The act of BREATHING out.
Elements of limited time intervals, contributing to particular results or situations.
Excessive accumulation of extravascular fluid in the lung, an indication of a serious underlying disease or disorder. Pulmonary edema prevents efficient PULMONARY GAS EXCHANGE in the PULMONARY ALVEOLI, and can be life-threatening.
The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
Procedure in which patients are induced into an unconscious state through use of various medications so that they do not feel pain during surgery.
Cells specialized to detect chemical substances and relay that information centrally in the nervous system. Chemoreceptor cells may monitor external stimuli, as in TASTE and OLFACTION, or internal stimuli, such as the concentrations of OXYGEN and CARBON DIOXIDE in the blood.
In the medical field, manikins are realistic, full-size models of human bodies used for teaching and practicing medical skills, such as CPR, intubation, or surgical procedures, as they provide a realistic and safe training environment without the use of actual patients.
All-purpose surfactant, wetting agent, and solubilizer used in the drug, cosmetics, and food industries. It has also been used in laxatives and as cerumenolytics. It is usually administered as either the calcium, potassium, or sodium salt.
The volume of air contained in the lungs at the end of a maximal inspiration. It is the equivalent to each of the following sums: VITAL CAPACITY plus RESIDUAL VOLUME; INSPIRATORY CAPACITY plus FUNCTIONAL RESIDUAL CAPACITY; TIDAL VOLUME plus INSPIRATORY RESERVE VOLUME plus functional residual capacity; or tidal volume plus inspiratory reserve volume plus EXPIRATORY RESERVE VOLUME plus residual volume.
The extra volume of air that can be expired with maximum effort beyond the level reached at the end of a normal, quiet expiration. Common abbreviation is ERV.
Washing liquid obtained from irrigation of the lung, including the BRONCHI and the PULMONARY ALVEOLI. It is generally used to assess biochemical, inflammatory, or infection status of the lung.
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)
Volume of circulating ERYTHROCYTES . It is usually measured by RADIOISOTOPE DILUTION TECHNIQUE.
The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).
The volume of air that is exhaled by a maximal expiration following a maximal inspiration.
Irregular HEART RATE caused by abnormal function of the SINOATRIAL NODE. It is characterized by a greater than 10% change between the maximum and the minimum sinus cycle length or 120 milliseconds.
Colloids with a gaseous dispersing phase and either liquid (fog) or solid (smoke) dispersed phase; used in fumigation or in inhalation therapy; may contain propellant agents.
Substances and drugs that lower the SURFACE TENSION of the mucoid layer lining the PULMONARY ALVEOLI.
Relatively complete absence of oxygen in one or more tissues.
The motor nerve of the diaphragm. The phrenic nerve fibers originate in the cervical spinal column (mostly C4) and travel through the cervical plexus to the diaphragm.
The outer margins of the thorax containing SKIN, deep FASCIA; THORACIC VERTEBRAE; RIBS; STERNUM; and MUSCLES.
Any disorder marked by obstruction of conducting airways of the lung. AIRWAY OBSTRUCTION may be acute, chronic, intermittent, or persistent.
Method for determining the circulating blood volume by introducing a known quantity of foreign substance into the blood and determining its concentration some minutes later when thorough mixing has occurred. From these two values the blood volume can be calculated by dividing the quantity of injected material by its concentration in the blood at the time of uniform mixing. Generally expressed as cubic centimeters or liters per kilogram of body weight.
Helium. A noble gas with the atomic symbol He, atomic number 2, and atomic weight 4.003. It is a colorless, odorless, tasteless gas that is not combustible and does not support combustion. It was first detected in the sun and is now obtained from natural gas. Medically it is used as a diluent for other gases, being especially useful with oxygen in the treatment of certain cases of respiratory obstruction, and as a vehicle for general anesthetics. (Dorland, 27th ed)
Timing the acquisition of imaging data to specific points in the breathing cycle to minimize image blurring and other motion artifacts. The images are used diagnostically and also interventionally to coordinate radiation treatment beam on/off cycles to protect healthy tissues when they move into the beam field during different times in the breathing cycle.
A type of oropharyngeal airway that provides an alternative to endotracheal intubation and standard mask anesthesia in certain patients. It is introduced into the hypopharynx to form a seal around the larynx thus permitting spontaneous or positive pressure ventilation without penetration of the larynx or esophagus. It is used in place of a facemask in routine anesthesia. The advantages over standard mask anesthesia are better airway control, minimal anesthetic gas leakage, a secure airway during patient transport to the recovery area, and minimal postoperative problems.
Agents causing the narrowing of the lumen of a bronchus or bronchiole.
Mechanical ventilation delivered to match the patient's efforts in breathing as detected by the interactive ventilation device.
The process of converting analog data such as continually measured voltage to discrete, digital form.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
The restoration to life or consciousness of one apparently dead. (Dorland, 27th ed)
Narrowing of the caliber of the BRONCHI, physiologically or as a result of pharmacological intervention.
A subspecialty of Pediatrics concerned with the newborn infant.
Complete or severe weakness of the muscles of respiration. This condition may be associated with MOTOR NEURON DISEASES; PERIPHERAL NERVE DISEASES; NEUROMUSCULAR JUNCTION DISEASES; SPINAL CORD DISEASES; injury to the PHRENIC NERVE; and other disorders.
The rate of airflow measured during a FORCED VITAL CAPACITY determination.
Application of positive pressure to the inspiratory phase when the patient has an artificial airway in place and is connected to a ventilator.
Three-dimensional representation to show anatomic structures. Models may be used in place of intact animals or organisms for teaching, practice, and study.
PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
The posture of an individual lying face down.
Absence of air in the entire or part of a lung, such as an incompletely inflated neonate lung or a collapsed adult lung. Pulmonary atelectasis can be caused by airway obstruction, lung compression, fibrotic contraction, or other factors.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.
That portion of the body that lies between the THORAX and the PELVIS.
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
The 10th cranial nerve. The vagus is a mixed nerve which contains somatic afferents (from skin in back of the ear and the external auditory meatus), visceral afferents (from the pharynx, larynx, thorax, and abdomen), parasympathetic efferents (to the thorax and abdomen), and efferents to striated muscle (of the larynx and pharynx).
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
Any hindrance to the passage of air into and out of the lungs.
The measurement of an organ in volume, mass, or heaviness.
Surgical incision of the trachea.
Application of positive pressure to the inspiratory phase of spontaneous respiration.
Muscles forming the ABDOMINAL WALL including RECTUS ABDOMINIS, external and internal oblique muscles, transversus abdominis, and quadratus abdominis. (from Stedman, 25th ed)
Artificial respiration (RESPIRATION, ARTIFICIAL) using an oxygenated fluid.
Non-therapeutic positive end-expiratory pressure occurring frequently in patients with severe airway obstruction. It can appear with or without the administration of external positive end-expiratory pressure (POSITIVE-PRESSURE RESPIRATION). It presents an important load on the inspiratory muscles which are operating at a mechanical disadvantage due to hyperinflation. Auto-PEEP may cause profound hypotension that should be treated by intravascular volume expansion, increasing the time for expiration, and/or changing from assist mode to intermittent mandatory ventilation mode. (From Harrison's Principles of Internal Medicine, 12th ed, p1127)
A quaternary ammonium parasympathomimetic agent with the muscarinic actions of ACETYLCHOLINE. It is hydrolyzed by ACETYLCHOLINESTERASE at a considerably slower rate than ACETYLCHOLINE and is more resistant to hydrolysis by nonspecific CHOLINESTERASES so that its actions are more prolonged. It is used as a parasympathomimetic bronchoconstrictor agent and as a diagnostic aid for bronchial asthma. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1116)
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
A condition of the newborn marked by DYSPNEA with CYANOSIS, heralded by such prodromal signs as dilatation of the alae nasi, expiratory grunt, and retraction of the suprasternal notch or costal margins, mostly frequently occurring in premature infants, children of diabetic mothers, and infants delivered by cesarean section, and sometimes with no apparent predisposing cause.
The circulation of the BLOOD through the LUNGS.
The continuous measurement of physiological processes, blood pressure, heart rate, renal output, reflexes, respiration, etc., in a patient or experimental animal; includes pharmacologic monitoring, the measurement of administered drugs or their metabolites in the blood, tissues, or urine.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
Devices that cause a liquid or solid to be converted into an aerosol (spray) or a vapor. It is used in drug administration by inhalation, humidification of ambient air, and in certain analytical instruments.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
Difficult or labored breathing.
The ratio of alveolar ventilation to simultaneous alveolar capillary blood flow in any part of the lung. (Stedman, 25th ed)
Body ventilators that assist ventilation by applying intermittent subatmospheric pressure around the thorax, abdomen, or airway and periodically expand the chest wall and inflate the lungs. They are relatively simple to operate and do not require tracheostomy. These devices include the tank ventilators ("iron lung"), Portalung, Pneumowrap, and chest cuirass ("tortoise shell").
Expenditure of energy during PHYSICAL ACTIVITY. Intensity of exertion may be measured by rate of OXYGEN CONSUMPTION; HEAT produced, or HEART RATE. Perceived exertion, a psychological measure of exertion, is included.
The posture of an individual lying face up.
An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
Respiratory retention of carbon dioxide. It may be chronic or acute.
The administration of drugs by the respiratory route. It includes insufflation into the respiratory tract.
The act of blowing a powder, vapor, or gas into any body cavity for experimental, diagnostic, or therapeutic purposes.
A small cluster of chemoreceptive and supporting cells located near the bifurcation of the internal carotid artery. The carotid body, which is richly supplied with fenestrated capillaries, senses the pH, carbon dioxide, and oxygen concentrations in the blood and plays a crucial role in their homeostatic control.
An abnormal increase in the amount of oxygen in the tissues and organs.
Part of the brain located in the MEDULLA OBLONGATA and PONS. It receives neural, chemical and hormonal signals, and controls the rate and depth of respiratory movements of the DIAPHRAGM and other respiratory muscles.
Techniques for administering artificial respiration without the need for INTRATRACHEAL INTUBATION.
Agents that cause an increase in the expansion of a bronchus or bronchial tubes.
Respiratory support system used primarily with rates of about 100 to 200/min with volumes of from about one to three times predicted anatomic dead space. Used to treat respiratory failure and maintain ventilation under severe circumstances.
Therapy whose basic objective is to restore the volume and composition of the body fluids to normal with respect to WATER-ELECTROLYTE BALANCE. Fluids may be administered intravenously, orally, by intermittent gavage, or by HYPODERMOCLYSIS.
The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.
A measure of the amount of WATER VAPOR in the air.
Diseases of the respiratory system in general or unspecified or for a specific respiratory disease not available.
Respiratory muscles that arise from the lower border of one rib and insert into the upper border of the adjoining rib, and contract during inspiration or respiration. (From Stedman, 25th ed)
Controlled physical activity which is performed in order to allow assessment of physiological functions, particularly cardiovascular and pulmonary, but also aerobic capacity. Maximal (most intense) exercise is usually required but submaximal exercise is also used.
Advanced and highly specialized care provided to medical or surgical patients whose conditions are life-threatening and require comprehensive care and constant monitoring. It is usually administered in specially equipped units of a health care facility.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
A reduction in the amount of air entering the pulmonary alveoli.
The position or attitude of the body.
An infant during the first month after birth.
A type of impedance plethysmography in which bioelectrical impedance is measured between electrodes positioned around the neck and around the lower thorax. It is used principally to calculate stroke volume and cardiac volume, but it is also related to myocardial contractility, thoracic fluid content, and circulation to the extremities.
Tomography using x-ray transmission and a computer algorithm to reconstruct the image.
Clinical manifestation consisting of a deficiency of carbon dioxide in arterial blood.
The tubular and cavernous organs and structures, by means of which pulmonary ventilation and gas exchange between ambient air and the blood are brought about.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
The volume of air remaining in the LUNGS at the end of a maximal expiration. Common abbreviation is RV.
A class of statistical methods applicable to a large set of probability distributions used to test for correlation, location, independence, etc. In most nonparametric statistical tests, the original scores or observations are replaced by another variable containing less information. An important class of nonparametric tests employs the ordinal properties of the data. Another class of tests uses information about whether an observation is above or below some fixed value such as the median, and a third class is based on the frequency of the occurrence of runs in the data. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1284; Corsini, Concise Encyclopedia of Psychology, 1987, p764-5)
Infection of the lung often accompanied by inflammation.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Devices intended to replace non-functioning organs. They may be temporary or permanent. Since they are intended always to function as the natural organs they are replacing, they should be differentiated from PROSTHESES AND IMPLANTS and specific types of prostheses which, though also replacements for body parts, are frequently cosmetic (EYE, ARTIFICIAL) as well as functional (ARTIFICIAL LIMBS).
Health care provided to a critically ill patient during a medical emergency or crisis.
Barriers used to separate and remove PARTICULATE MATTER from air.
Care of patients with deficiencies and abnormalities associated with the cardiopulmonary system. It includes the therapeutic use of medical gases and their administrative apparatus, environmental control systems, humidification, aerosols, ventilatory support, bronchopulmonary drainage and exercise, respiratory rehabilitation, assistance with cardiopulmonary resuscitation, and maintenance of natural, artificial, and mechanical airways.
Surgical formation of an opening into the trachea through the neck, or the opening so created.
The airflow rate measured during the first liter expired after the first 200 ml have been exhausted during a FORCED VITAL CAPACITY determination. Common abbreviations are MEFR, FEF 200-1200, and FEF 0.2-1.2.
Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.
The resistance to the flow of either alternating or direct electrical current.

Breathing responses to small inspiratory threshold loads in humans. (1/1287)

To investiage the effect of inspiratory threshold load (ITL) on breathing, all previous work studied loads that were much greater than would be encountered under pathophysiological conditions. We hypothesized that mild ITL from 2.5 to 20 cmH2O is sufficient to modify control and sensation of breathing. The study was performed in healthy subjects. The results demonstrated that with mild ITL 1) inspiratory difficulty sensation could be perceived at an ITL of 2.5 cmH2O; 2) tidal volume increased without change in breathing frequency, resulting in hyperpnea; and 3) although additional time was required for inspiratory pressure to attain the threshold before inspiratory flow was initiated, the total inspiratory muscle contraction time remained constant. This resulted in shortening of the available time for inspiratory flow, so that the tidal volume was maintained or increased by significant increase in mean inspiratory flow. On the basis of computer simulation, we conclude that the mild ITL is sufficient to increase breathing sensation and alter breathing control, presumably aiming at maintaining a certain level of ventilation but minimizing the energy consumption of the inspiratory muscles.  (+info)

Capsaicin-sensitive C-fiber-mediated protective responses in ozone inhalation in rats. (2/1287)

To assess the role of lung sensory C fibers during and after inhalation of 1 part/million ozone for 8 h, we compared breathing pattern responses and epithelial injury-inflammation-repair in rats depleted of C fibers by systemic administration of capsaicin as neonates and in vehicle-treated control animals. Capsaicin-treated rats did not develop ozone-induced rapid, shallow breathing. Capsaicin-treated rats showed more severe necrosis in the nasal cavity and greater inflammation throughout the respiratory tract than did control rats exposed to ozone. Incorporation of 5-bromo-2'-deoxyuridine (a marker of DNA synthesis associated with proliferation) into terminal bronchiolar epithelial cells was not significantly affected by capsaicin treatment in rats exposed to ozone. However, when normalized to the degree of epithelial necrosis present in each rat studied, there was less 5-bromo-2'-deoxyuridine labeling in the terminal bronchioles of capsaicin-treated rats. These observations suggest that the ozone-induced release of neuropeptides does not measurably contribute to airway inflammation but may play a role in modulating basal and reparative airway epithelial cell proliferation.  (+info)

Breathing patterns during slow and fast ramp exercise in man. (3/1287)

Breathing frequency (fb), tidal volume (VT), and respiratory timing during slow (SR, 8 W min-1) and fast (FR, 65 W min-1) ramp exercise to exhaustion on a cycle ergometer was examined in seven healthy male subjects. Expiratory ventilation (VE), pulmonary gas exchange (VO2 and VCO2) and end-tidal gas tensions (PET,O2 and PET,CO2) were determined using breath-by-breath techniques. Arterialized venous blood was sampled from a dorsal hand vein at 2 min intervals during SR and 30 s intervals during FR and analysed for arterial plasma PCO2 (PaCO2). PET,CO2 increased with increasing work rates (WRs) below the ventilatory threshold (VT); at WRs > or = 90% VO2,max, PET,CO2 was reduced (P < 0.05) below 0 W values in SR but not in FR.fb and VT were similar for SR and FR at all submaximal WRs, resulting in a similar VE. At exhaustion VE was similar but fb was higher (P < 0.05) and VT was lower (P < 0.05) in SR (fb, 51 +/- 10 breaths min-1; VT, 2590 +/- 590 ml) than in FR (fb, 42 +/- 8 breaths min-1; VT, 3050 +/- 470 ml). The time of expiration (TE) decreased with increasing WR, but there was no difference between SR and FR. The time of inspiration (TI) decreased at exercise intensities > or = VT; at exhaustion, TI was shorter (P < 0.05) during SR (0.512 +/- 0.097 s) than during FR (0.753 +/- 0.100 s). The TI to total breath duration (TI/TTot) and the inspiratory flow (VT/TI) were similar during SR and FR at all submaximal exercise intensities; at VO2,max, TI/TTot was lower (P < 0.05) and VT/TI was higher (P < 0.05) during SR (TI/TTot, 0.473 +/- 0.030; VT/TI, 5.092 +/- 0.377 l s-1) than during FR (TI/TTot, 0.567 +/- 0.050; VT/TI, 4.117 +/- 0.635 l s-1). These results suggest that during progressive exercise, breathing pattern and respiratory timing may be determined, at least at submaximal work rates, independently of alveolar and arterial PCO2.  (+info)

Vital capacity and tidal volume preoxygenation with a mouthpiece. (4/1287)

We have measured oxygen wash-in in 20 volunteers undergoing preoxygenation with a face mask, mouthpiece alone and a mouthpiece with a noseclip, in a crossover study. Tidal volume breathing and maximal deep breath techniques were studied with each type of equipment. When tidal volume breathing was used, the face mask and mouthpiece with noseclip were comparable, but the mouthpiece alone achieved a lower end-expiratory oxygen concentration than the two other methods after 3 min (P < 0.001 and P < 0.01), and after 5 min (P < 0.05 in each case). Conversely, during preoxygenation with vital capacity breaths, the mouthpiece and mouthpiece with noseclip were comparable, and both were more effective than the face mask (P < 0.001). In a second study, 20 patients who had undergone preoxygenation before induction of anaesthesia were asked later if they would have preferred the face mask or mouthpiece for this procedure. Significantly more patients (14 of 18 who expressed a preference) favoured the mouthpiece (P < 0.05; confidence limits 0.56-0.92).  (+info)

Compensatory alveolar growth normalizes gas-exchange function in immature dogs after pneumonectomy. (5/1287)

To determine the extent and sources of adaptive response in gas-exchange to major lung resection during somatic maturation, immature male foxhounds underwent right pneumonectomy (R-Pnx, n = 5) or right thoracotomy without pneumonectomy (Sham, n = 6) at 2 mo of age. One year after surgery, exercise capacity and pulmonary gas-exchange were determined during treadmill exercise. Lung diffusing capacity (DL) and cardiac output were measured by a rebreathing technique. In animals after R-Pnx, maximal O2 uptake, lung volume, arterial blood gases, and DL during exercise were completely normal. Postmortem morphometric analysis 18 mo after R-Pnx (n = 3) showed a vigorous compensatory increase in alveolar septal tissue volume involving all cellular compartments of the septum compared with the control lung; as a result, alveolar-capillary surface areas and DL estimated by morphometry were restored to normal. In both groups, estimates of DL by the morphometric method agreed closely with estimates obtained by the physiological method during peak exercise. These data show that extensive lung resection in immature dogs stimulates a vigorous compensatory growth of alveolar tissue in excess of maturational lung growth, resulting in complete normalization of aerobic capacity and gas-exchange function at maturity.  (+info)

Expiratory time determined by individual anxiety levels in humans. (6/1287)

We have previously found that individual anxiety levels influence respiratory rates in physical load and mental stress (Y. Masaoka and I. Homma. Int. J. Psychophysiol. 27: 153-159, 1997). On the basis of that study, in the present study we investigated the metabolic outputs during tests and analyzed the respiratory timing relationship between inspiration and expiration, taking into account individual anxiety levels. Disregarding anxiety levels, there were correlations between O2 consumption (VO2) and minute ventilation (VE) and between VO2 and tidal volume in the physical load test, but no correlations were observed in the noxious audio stimulation test. There was a volume-based increase in respiratory patterns in physical load; however, VE increased not only for the adjustment of metabolic needs but also for individual mental factors; anxiety participated in this increase. In the high-anxiety group, the VE-to-VO2 ratio, indicating ventilatory efficiency, increased in both tests. In the high-anxiety group, increases in respiratory rate contributed to a VE increase, and there were negative correlations between expiratory time and anxiety scores in both tests. In an awake state, the higher neural structure may dominantly affect the mechanism of respiratory rhythm generation. We focus on the relationship between expiratory time and anxiety and show diagrams of respiratory output, allowing for individual personality.  (+info)

Evaluation of pulmonary resistance and maximal expiratory flow measurements during exercise in humans. (7/1287)

To evaluate methods used to document changes in airway function during and after exercise, we studied nine subjects with exercise-induced asthma and five subjects without asthma. Airway function was assessed from measurements of pulmonary resistance (RL) and forced expiratory vital capacity maneuvers. In the asthmatic subjects, forced expiratory volume in 1 s (FEV1) fell 24 +/- 14% and RL increased 176 +/- 153% after exercise, whereas normal subjects experienced no change in airway function (RL -3 +/- 8% and FEV1 -4 +/- 5%). During exercise, there was a tendency for FEV1 to increase in the asthmatic subjects but not in the normal subjects. RL, however, showed a slight increase during exercise in both groups. Changes in lung volumes encountered during exercise were small and had no consistent effect on RL. The small increases in RL during exercise could be explained by the nonlinearity of the pressure-flow relationship and the increased tidal breathing flows associated with exercise. In the asthmatic subjects, a deep inspiration (DI) caused a small, significant, transient decrease in RL 15 min after exercise. There was no change in RL in response to DI during exercise in either asthmatic or nonasthmatic subjects. When percent changes in RL and FEV1 during and after exercise were compared, there was close agreement between the two measurements of change in airway function. In the groups of normal and mildly asthmatic subjects, we conclude that changes in lung volume and DIs had no influence on RL during exercise. Increases in tidal breathing flows had only minor influence on measurements of RL during exercise. Furthermore, changes in RL and in FEV1 produce equivalent indexes of the variations in airway function during and after exercise.  (+info)

Dyspnoea, peripheral airway involvement and respiratory muscle effort in patients with type I diabetes mellitus under good metabolic control. (8/1287)

Dyspnoea and pulmonary dysfunction have recently been associated with Type I (insulin-dependent) diabetes mellitus. The putative role of altered pulmonary mechanics and of performance of inspiratory muscles in inducing dyspnoea has not been yet assessed in Type I diabetes. To better focus on this topic we evaluated nine patients with Type I diabetes mellitus, aged 19 to 48 years with good and stable metabolic control, without a history of smoking and microvascular complications, alongside a group of 14 healthy control subjects. In each subject, pulmonary volumes, static and dynamic compliance, pleural pressure swings (Pplsw), maximal inspiratory pressures (Pplsn), Pplsw(%Pplsn), a measure of respiratory muscle effort, and tension-time index [TTI=TI/TTOTxPplsw(%Pplsn)] were measured (TI=inspiratory time;TTOT=total time of the respiratory cycle). All subjects were studied at baseline and during hypoxic rebreathing. Patients had normal pulmonary volumes. During hypoxic rebreathing, a normal change in respiratory muscle effort [DeltaPplsw(%Pplsn)/DeltaSaO2] and DeltaTTI/DeltaSaO2, and a lower change in tidal volume versus change in oxygen saturation [DeltaVT(% vital capacity)/DeltaSaO2], resulted in a higher ratio of respiratory effort to tidal volume [Pplsw(%Pplsn)/VT(% vital capacity)], a measure of neuroventilatory dissociation of the respiratory pump. Hypoxic dyspnoea, assessed by a modified Borg scale, showed a greater rate of rise (DeltaBorg/DeltaSaO2) and a greater increase for a given level of respiratory effort in patients. Moreover, neuroventilatory dissociation related to the expression of peripheral airway involvement, as assessed in terms of low dynamic compliance, and to concurrent change in dyspnoea sensation. Patients with Type I diabetes mellitus under good metabolic control and with normal lung volumes may have abnormal peripheral airway function. The latter is thought to be responsible for the association between dyspnoea sensation and neuroventilatory dissociation.  (+info)

Tidal volume (Vt) is the amount of air that moves into or out of the lungs during normal, resting breathing. It is the difference between the volume of air in the lungs at the end of a normal expiration and the volume at the end of a normal inspiration. In other words, it's the volume of each breath you take when you are not making any effort to breathe more deeply.

The average tidal volume for an adult human is around 500 milliliters (ml) per breath, but this can vary depending on factors such as age, sex, size, and fitness level. During exercise or other activities that require increased oxygen intake, tidal volume may increase to meet the body's demands for more oxygen.

Tidal volume is an important concept in respiratory physiology and clinical medicine, as it can be used to assess lung function and diagnose respiratory disorders such as chronic obstructive pulmonary disease (COPD) or asthma.

Artificial respiration is an emergency procedure that can be used to provide oxygen to a person who is not breathing or is breathing inadequately. It involves manually forcing air into the lungs, either by compressing the chest or using a device to deliver breaths. The goal of artificial respiration is to maintain adequate oxygenation of the body's tissues and organs until the person can breathe on their own or until advanced medical care arrives. Artificial respiration may be used in conjunction with cardiopulmonary resuscitation (CPR) in cases of cardiac arrest.

Respiratory mechanics refers to the biomechanical properties and processes that involve the movement of air through the respiratory system during breathing. It encompasses the mechanical behavior of the lungs, chest wall, and the muscles of respiration, including the diaphragm and intercostal muscles.

Respiratory mechanics includes several key components:

1. **Compliance**: The ability of the lungs and chest wall to expand and recoil during breathing. High compliance means that the structures can easily expand and recoil, while low compliance indicates greater resistance to expansion and recoil.
2. **Resistance**: The opposition to airflow within the respiratory system, primarily due to the friction between the air and the airway walls. Airway resistance is influenced by factors such as airway diameter, length, and the viscosity of the air.
3. **Lung volumes and capacities**: These are the amounts of air present in the lungs during different phases of the breathing cycle. They include tidal volume (the amount of air inspired or expired during normal breathing), inspiratory reserve volume (additional air that can be inspired beyond the tidal volume), expiratory reserve volume (additional air that can be exhaled beyond the tidal volume), and residual volume (the air remaining in the lungs after a forced maximum exhalation).
4. **Work of breathing**: The energy required to overcome the resistance and elastic forces during breathing. This work is primarily performed by the respiratory muscles, which contract to generate negative intrathoracic pressure and expand the chest wall, allowing air to flow into the lungs.
5. **Pressure-volume relationships**: These describe how changes in lung volume are associated with changes in pressure within the respiratory system. Important pressure components include alveolar pressure (the pressure inside the alveoli), pleural pressure (the pressure between the lungs and the chest wall), and transpulmonary pressure (the difference between alveolar and pleural pressures).

Understanding respiratory mechanics is crucial for diagnosing and managing various respiratory disorders, such as chronic obstructive pulmonary disease (COPD), asthma, and restrictive lung diseases.

Medical Definition of Respiration:

Respiration, in physiology, is the process by which an organism takes in oxygen and gives out carbon dioxide. It's also known as breathing. This process is essential for most forms of life because it provides the necessary oxygen for cellular respiration, where the cells convert biochemical energy from nutrients into adenosine triphosphate (ATP), and releases waste products, primarily carbon dioxide.

In humans and other mammals, respiration is a two-stage process:

1. Breathing (or external respiration): This involves the exchange of gases with the environment. Air enters the lungs through the mouth or nose, then passes through the pharynx, larynx, trachea, and bronchi, finally reaching the alveoli where the actual gas exchange occurs. Oxygen from the inhaled air diffuses into the blood, while carbon dioxide, a waste product of metabolism, diffuses from the blood into the alveoli to be exhaled.

2. Cellular respiration (or internal respiration): This is the process by which cells convert glucose and other nutrients into ATP, water, and carbon dioxide in the presence of oxygen. The carbon dioxide produced during this process then diffuses out of the cells and into the bloodstream to be exhaled during breathing.

In summary, respiration is a vital physiological function that enables organisms to obtain the necessary oxygen for cellular metabolism while eliminating waste products like carbon dioxide.

Mechanical Ventilators are medical devices that assist with breathing by providing mechanical ventilation to patients who are unable to breathe sufficiently on their own. These machines deliver breaths to the patient through an endotracheal tube or a tracheostomy tube, which is placed in the windpipe (trachea). Mechanical Ventilators can be set to deliver breaths at specific rates and volumes, and they can also be adjusted to provide varying levels of positive end-expiratory pressure (PEEP) to help keep the alveoli open and improve oxygenation.

Mechanical ventilation is typically used in critical care settings such as intensive care units (ICUs), and it may be employed for a variety of reasons, including respiratory failure, sedation, neuromuscular disorders, or surgery. Prolonged use of mechanical ventilation can lead to complications such as ventilator-associated pneumonia, muscle weakness, and decreased cardiac function, so the goal is usually to wean patients off the ventilator as soon as possible.

Positive-pressure respiration is a type of mechanical ventilation where positive pressure is applied to the airway and lungs, causing them to expand and inflate. This can be used to support or replace spontaneous breathing in patients who are unable to breathe effectively on their own due to conditions such as respiratory failure, neuromuscular disorders, or sedation for surgery.

During positive-pressure ventilation, a mechanical ventilator delivers breaths to the patient through an endotracheal tube or a tracheostomy tube. The ventilator is set to deliver a specific volume or pressure of air with each breath, and the patient's breathing is synchronized with the ventilator to ensure proper delivery of the breaths.

Positive-pressure ventilation can help improve oxygenation and remove carbon dioxide from the lungs, but it can also have potential complications such as barotrauma (injury to lung tissue due to excessive pressure), volutrauma (injury due to overdistention of the lungs), hemodynamic compromise (decreased blood pressure and cardiac output), and ventilator-associated pneumonia. Therefore, careful monitoring and adjustment of ventilator settings are essential to minimize these risks and provide safe and effective respiratory support.

Pulmonary ventilation, also known as pulmonary respiration or simply ventilation, is the process of moving air into and out of the lungs to facilitate gas exchange. It involves two main phases: inhalation (or inspiration) and exhalation (or expiration). During inhalation, the diaphragm and external intercostal muscles contract, causing the chest volume to increase and the pressure inside the chest to decrease, which then draws air into the lungs. Conversely, during exhalation, these muscles relax, causing the chest volume to decrease and the pressure inside the chest to increase, which pushes air out of the lungs. This process ensures that oxygen-rich air from the atmosphere enters the alveoli (air sacs in the lungs), where it can diffuse into the bloodstream, while carbon dioxide-rich air from the bloodstream in the capillaries surrounding the alveoli is expelled out of the body.

Lung compliance is a measure of the ease with which the lungs expand and is defined as the change in lung volume for a given change in transpulmonary pressure. It is often expressed in units of liters per centimeter of water (L/cm H2O). A higher compliance indicates that the lungs are more easily distensible, while a lower compliance suggests that the lungs are stiffer and require more force to expand. Lung compliance can be affected by various conditions such as pulmonary fibrosis, pneumonia, acute respiratory distress syndrome (ARDS), and chronic obstructive pulmonary disease (COPD).

Ventilator-Induced Lung Injury (VILI) is a type of lung injury that can occur in patients who require mechanical ventilation to assist their breathing. It's caused by the application of excessive pressure or volume to the lungs during the process of mechanical ventilation, which can lead to damage of the alveoli (tiny air sacs in the lungs). This can result in inflammation, increased permeability of the alveolar-capillary membrane, and potentially even progressive lung dysfunction.

The risk factors for VILI include high tidal volumes (the amount of air moved into and out of the lungs during each breath), high inspiratory pressures, and high levels of positive end-expiratory pressure (PEEP). To minimize the risk of VILI, clinicians often use a lung protective ventilation strategy that involves using lower tidal volumes and limiting inspiratory pressures.

It's important to note that while mechanical ventilation is a lifesaving intervention for many critically ill patients, it is not without risks. VILI is one of the potential complications of this therapy, and clinicians must be mindful of this risk when managing mechanically ventilated patients.

Respiratory dead space is the portion of each tidal volume (the amount of air that moves in and out of the lungs during normal breathing) that does not participate in gas exchange. It mainly consists of the anatomical dead space, which includes the conducting airways such as the trachea, bronchi, and bronchioles, where no alveoli are present for gas exchange to occur.

Additionally, alveolar dead space can also contribute to respiratory dead space when alveoli are perfused inadequately or not at all due to conditions like pulmonary embolism, lung consolidation, or impaired circulation. In these cases, even though air reaches the alveoli, insufficient blood flow prevents efficient gas exchange from taking place.

The sum of anatomical and alveolar dead space is referred to as physiological dead space. An increased respiratory dead space can lead to ventilation-perfusion mismatch and impaired oxygenation, making it a critical parameter in assessing respiratory function, particularly during mechanical ventilation in critically ill patients.

Lung volume measurements are clinical tests that determine the amount of air inhaled, exhaled, and present in the lungs at different times during the breathing cycle. These measurements include:

1. Tidal Volume (TV): The amount of air inhaled or exhaled during normal breathing, usually around 500 mL in resting adults.
2. Inspiratory Reserve Volume (IRV): The additional air that can be inhaled after a normal inspiration, approximately 3,000 mL in adults.
3. Expiratory Reserve Volume (ERV): The extra air that can be exhaled after a normal expiration, about 1,000-1,200 mL in adults.
4. Residual Volume (RV): The air remaining in the lungs after a maximal exhalation, approximately 1,100-1,500 mL in adults.
5. Total Lung Capacity (TLC): The total amount of air the lungs can hold at full inflation, calculated as TV + IRV + ERV + RV, around 6,000 mL in adults.
6. Functional Residual Capacity (FRC): The volume of air remaining in the lungs after a normal expiration, equal to ERV + RV, about 2,100-2,700 mL in adults.
7. Inspiratory Capacity (IC): The maximum amount of air that can be inhaled after a normal expiration, equal to TV + IRV, around 3,500 mL in adults.
8. Vital Capacity (VC): The total volume of air that can be exhaled after a maximal inspiration, calculated as IC + ERV, approximately 4,200-5,600 mL in adults.

These measurements help assess lung function and identify various respiratory disorders such as chronic obstructive pulmonary disease (COPD), asthma, and restrictive lung diseases.

Respiratory Distress Syndrome, Adult (RDSa or ARDS), also known as Acute Respiratory Distress Syndrome, is a severe form of acute lung injury characterized by rapid onset of widespread inflammation in the lungs. This results in increased permeability of the alveolar-capillary membrane, pulmonary edema, and hypoxemia (low oxygen levels in the blood). The inflammation can be triggered by various direct or indirect insults to the lung, such as sepsis, pneumonia, trauma, or aspiration.

The hallmark of ARDS is the development of bilateral pulmonary infiltrates on chest X-ray, which can resemble pulmonary edema, but without evidence of increased left atrial pressure. The condition can progress rapidly and may require mechanical ventilation with positive end-expiratory pressure (PEEP) to maintain adequate oxygenation and prevent further lung injury.

The management of ARDS is primarily supportive, focusing on protecting the lungs from further injury, optimizing oxygenation, and providing adequate nutrition and treatment for any underlying conditions. The use of low tidal volumes and limiting plateau pressures during mechanical ventilation have been shown to improve outcomes in patients with ARDS.

Carbon dioxide (CO2) is a colorless, odorless gas that is naturally present in the Earth's atmosphere. It is a normal byproduct of cellular respiration in humans, animals, and plants, and is also produced through the combustion of fossil fuels such as coal, oil, and natural gas.

In medical terms, carbon dioxide is often used as a respiratory stimulant and to maintain the pH balance of blood. It is also used during certain medical procedures, such as laparoscopic surgery, to insufflate (inflate) the abdominal cavity and create a working space for the surgeon.

Elevated levels of carbon dioxide in the body can lead to respiratory acidosis, a condition characterized by an increased concentration of carbon dioxide in the blood and a decrease in pH. This can occur in conditions such as chronic obstructive pulmonary disease (COPD), asthma, or other lung diseases that impair breathing and gas exchange. Symptoms of respiratory acidosis may include shortness of breath, confusion, headache, and in severe cases, coma or death.

Blood volume refers to the total amount of blood present in an individual's circulatory system at any given time. It is the combined volume of both the plasma (the liquid component of blood) and the formed elements (such as red and white blood cells and platelets) in the blood. In a healthy adult human, the average blood volume is approximately 5 liters (or about 1 gallon). However, blood volume can vary depending on several factors, including age, sex, body weight, and overall health status.

Blood volume plays a critical role in maintaining proper cardiovascular function, as it affects blood pressure, heart rate, and the delivery of oxygen and nutrients to tissues throughout the body. Changes in blood volume can have significant impacts on an individual's health and may be associated with various medical conditions, such as dehydration, hemorrhage, heart failure, and liver disease. Accurate measurement of blood volume is essential for diagnosing and managing these conditions, as well as for guiding treatment decisions in clinical settings.

Air pressure, also known as atmospheric pressure, is the force exerted by the weight of air in the atmosphere on a surface. It is measured in units such as pounds per square inch (psi), hectopascals (hPa), or inches of mercury (inHg). The standard atmospheric pressure at sea level is defined as 101,325 Pa (14.7 psi/1013 hPa/29.92 inHg). Changes in air pressure can be used to predict weather patterns and are an important factor in the study of aerodynamics and respiratory physiology.

Pulmonary gas exchange is the process by which oxygen (O2) from inhaled air is transferred to the blood, and carbon dioxide (CO2), a waste product of metabolism, is removed from the blood and exhaled. This process occurs in the lungs, primarily in the alveoli, where the thin walls of the alveoli and capillaries allow for the rapid diffusion of gases between them. The partial pressure gradient between the alveolar air and the blood in the pulmonary capillaries drives this diffusion process. Oxygen-rich blood is then transported to the body's tissues, while CO2-rich blood returns to the lungs to be exhaled.

Respiratory rate is the number of breaths a person takes per minute. It is typically measured by counting the number of times the chest rises and falls in one minute. Normal respiratory rate at rest for an adult ranges from 12 to 20 breaths per minute. An increased respiratory rate (tachypnea) or decreased respiratory rate (bradypnea) can be a sign of various medical conditions, such as lung disease, heart failure, or neurological disorders. It is an important vital sign that should be regularly monitored in clinical settings.

Airway resistance is a measure of the opposition to airflow during breathing, which is caused by the friction between the air and the walls of the respiratory tract. It is an important parameter in respiratory physiology because it can affect the work of breathing and gas exchange.

Airway resistance is usually expressed in units of cm H2O/L/s or Pa·s/m, and it can be measured during spontaneous breathing or during forced expiratory maneuvers, such as those used in pulmonary function testing. Increased airway resistance can result from a variety of conditions, including asthma, chronic obstructive pulmonary disease (COPD), bronchitis, and bronchiectasis. Decreased airway resistance can be seen in conditions such as emphysema or after a successful bronchodilator treatment.

Hypercapnia is a state of increased carbon dioxide (CO2) concentration in the blood, typically defined as an arterial CO2 tension (PaCO2) above 45 mmHg. It is often associated with conditions that impair gas exchange or eliminate CO2 from the body, such as chronic obstructive pulmonary disease (COPD), severe asthma, respiratory failure, or certain neuromuscular disorders. Hypercapnia can cause symptoms such as headache, confusion, shortness of breath, and in severe cases, it can lead to life-threatening complications such as respiratory acidosis, coma, and even death if not promptly treated.

Inhalation is the act or process of breathing in where air or other gases are drawn into the lungs. It's also known as inspiration. This process involves several muscles, including the diaphragm and intercostal muscles between the ribs, working together to expand the chest cavity and decrease the pressure within the thorax, which then causes air to flow into the lungs.

In a medical context, inhalation can also refer to the administration of medications or therapeutic gases through the respiratory tract, typically using an inhaler or nebulizer. This route of administration allows for direct delivery of the medication to the lungs, where it can be quickly absorbed into the bloodstream and exert its effects.

Barotrauma is a type of injury that occurs when there is a difference in pressure between the external environment and the internal body, leading to damage to body tissues. It commonly affects gas-filled spaces in the body, such as the lungs, middle ear, or sinuses.

In medical terms, barotrauma refers to the damage caused by changes in pressure that occur rapidly, such as during scuba diving, flying in an airplane, or receiving treatment in a hyperbaric chamber. These rapid changes in pressure can cause the gas-filled spaces in the body to expand or contract, leading to injury.

For example, during descent while scuba diving, the pressure outside the body increases, and if the diver does not equalize the pressure in their middle ear by swallowing or yawning, the increased pressure can cause the eardrum to rupture, resulting in barotrauma. Similarly, rapid ascent while flying can cause the air in the lungs to expand, leading to lung overexpansion injuries such as pneumothorax or arterial gas embolism.

Prevention of barotrauma involves equalizing pressure in the affected body spaces during changes in pressure and avoiding diving or flying with respiratory infections or other conditions that may increase the risk of injury. Treatment of barotrauma depends on the severity and location of the injury and may include pain management, antibiotics, surgery, or hyperbaric oxygen therapy.

A lung is a pair of spongy, elastic organs in the chest that work together to enable breathing. They are responsible for taking in oxygen and expelling carbon dioxide through the process of respiration. The left lung has two lobes, while the right lung has three lobes. The lungs are protected by the ribcage and are covered by a double-layered membrane called the pleura. The trachea divides into two bronchi, which further divide into smaller bronchioles, leading to millions of tiny air sacs called alveoli, where the exchange of gases occurs.

Lung injury, also known as pulmonary injury, refers to damage or harm caused to the lung tissue, blood vessels, or air sacs (alveoli) in the lungs. This can result from various causes such as infection, trauma, exposure to harmful substances, or systemic diseases. Common types of lung injuries include acute respiratory distress syndrome (ARDS), pneumonia, and chemical pneumonitis. Symptoms may include difficulty breathing, cough, chest pain, and decreased oxygen levels in the blood. Treatment depends on the underlying cause and may include medications, oxygen therapy, or mechanical ventilation.

Work of breathing (WOB) is a term used in respiratory physiology to describe the amount of energy expended by the respiratory muscles to overcome the elastic and resistive forces in the lungs and chest wall during breathing. It is usually measured in joules per liter (J/L) or in breaths per minute (BPM).

WOB can be increased in various lung diseases, such as chronic obstructive pulmonary disease (COPD), asthma, and interstitial lung disease, due to increased airway resistance or decreased lung compliance. Increased WOB can lead to respiratory muscle fatigue, decreased exercise tolerance, and reduced quality of life.

WOB can be measured noninvasively using techniques such as esophageal pressure monitoring or transdiaphragmatic pressure measurement, or invasively through the use of indwelling catheters in the pleural space or within the airways. These measurements are often used in research settings to evaluate the effectiveness of various treatments for respiratory disorders.

Respiratory Function Tests (RFTs) are a group of medical tests that measure how well your lungs take in and exhale air, and how well they transfer oxygen and carbon dioxide into and out of your blood. They can help diagnose certain lung disorders, measure the severity of lung disease, and monitor response to treatment.

RFTs include several types of tests, such as:

1. Spirometry: This test measures how much air you can exhale and how quickly you can do it. It's often used to diagnose and monitor conditions like asthma, chronic obstructive pulmonary disease (COPD), and other lung diseases.
2. Lung volume testing: This test measures the total amount of air in your lungs. It can help diagnose restrictive lung diseases, such as pulmonary fibrosis or sarcoidosis.
3. Diffusion capacity testing: This test measures how well oxygen moves from your lungs into your bloodstream. It's often used to diagnose and monitor conditions like pulmonary fibrosis, interstitial lung disease, and other lung diseases that affect the ability of the lungs to transfer oxygen to the blood.
4. Bronchoprovocation testing: This test involves inhaling a substance that can cause your airways to narrow, such as methacholine or histamine. It's often used to diagnose and monitor asthma.
5. Exercise stress testing: This test measures how well your lungs and heart work together during exercise. It's often used to diagnose lung or heart disease.

Overall, Respiratory Function Tests are an important tool for diagnosing and managing a wide range of lung conditions.

Functional Residual Capacity (FRC) is the volume of air that remains in the lungs after normal expiration during quiet breathing. It represents the sum of the residual volume (RV) and the expiratory reserve volume (ERV). The FRC is approximately 2.5-3.5 liters in a healthy adult. This volume of air serves to keep the alveoli open and maintain oxygenation during periods of quiet breathing, as well as providing a reservoir for additional ventilation during increased activity or exercise.

Blood gas analysis is a medical test that measures the levels of oxygen and carbon dioxide in the blood, as well as the pH level, which indicates the acidity or alkalinity of the blood. This test is often used to evaluate lung function, respiratory disorders, and acid-base balance in the body. It can also be used to monitor the effectiveness of treatments for conditions such as chronic obstructive pulmonary disease (COPD), asthma, and other respiratory illnesses. The analysis is typically performed on a sample of arterial blood, although venous blood may also be used in some cases.

Oxygen is a colorless, odorless, tasteless gas that constitutes about 21% of the earth's atmosphere. It is a crucial element for human and most living organisms as it is vital for respiration. Inhaled oxygen enters the lungs and binds to hemoglobin in red blood cells, which carries it to tissues throughout the body where it is used to convert nutrients into energy and carbon dioxide, a waste product that is exhaled.

Medically, supplemental oxygen therapy may be provided to patients with conditions such as chronic obstructive pulmonary disease (COPD), pneumonia, heart failure, or other medical conditions that impair the body's ability to extract sufficient oxygen from the air. Oxygen can be administered through various devices, including nasal cannulas, face masks, and ventilators.

Plethysmography is a non-invasive medical technique used to measure changes in volume or blood flow within an organ or body part, typically in the lungs or extremities. There are several types of plethysmography, including:

1. **Whole Body Plethysmography (WBP):** This type of plethysmography is used to assess lung function and volumes by measuring changes in pressure within a sealed chamber that contains the patient's entire body except for their head. The patient breathes normally while wearing a nose clip, allowing technicians to analyze respiratory patterns, airflow, and lung volume changes.
2. **Segmental or Local Plethysmography:** This technique measures volume or blood flow changes in specific body parts, such as the limbs or digits. It can help diagnose and monitor conditions affecting peripheral circulation, like deep vein thrombosis, arterial occlusive disease, or Raynaud's phenomenon.
3. **Impedance Plethysmography (IPG):** This non-invasive method uses electrical impedance to estimate changes in blood volume within an organ or body part. By applying a small electrical current and measuring the opposition to flow (impedance), technicians can determine variations in blood volume, which can help diagnose conditions like deep vein thrombosis or heart failure.
4. **Optical Plethysmography:** This technique uses light to measure changes in blood volume, typically in the skin or mucous membranes. By shining a light on the area and analyzing the reflected or transmitted light, technicians can detect variations in blood volume related to cardiac output, respiration, or other physiological factors.

Overall, plethysmography is an essential tool for diagnosing and monitoring various medical conditions affecting circulation, respiratory function, and organ volumes.

Whole-body plethysmography is a non-invasive medical technique used to measure changes in the volume of air in the lungs and chest during breathing. It is often utilized in the diagnosis and assessment of various respiratory disorders such as chronic obstructive pulmonary disease (COPD), asthma, and restrictive lung diseases.

During whole-body plethysmography, the patient enters a sealed, clear chamber, usually in a standing or sitting position. The patient is instructed to breathe normally while the machine measures changes in pressure within the chamber as the chest and abdomen move during respiration. These measurements are then used to calculate lung volume, airflow, and other respiratory parameters.

This technique provides valuable information about the functional status of the lungs and can help healthcare providers make informed decisions regarding diagnosis, treatment planning, and disease monitoring.

Respiratory muscles are a group of muscles involved in the process of breathing. They include the diaphragm, intercostal muscles (located between the ribs), scalene muscles (located in the neck), and abdominal muscles. These muscles work together to allow the chest cavity to expand or contract, which draws air into or pushes it out of the lungs. The diaphragm is the primary muscle responsible for breathing, contracting to increase the volume of the chest cavity and draw air into the lungs during inhalation. The intercostal muscles help to further expand the ribcage, while the abdominal muscles assist in exhaling by compressing the abdomen and pushing up on the diaphragm.

Hyperventilation is a medical condition characterized by an increased respiratory rate and depth, resulting in excessive elimination of carbon dioxide (CO2) from the body. This leads to hypocapnia (low CO2 levels in the blood), which can cause symptoms such as lightheadedness, dizziness, confusion, tingling sensations in the extremities, and muscle spasms. Hyperventilation may occur due to various underlying causes, including anxiety disorders, lung diseases, neurological conditions, or certain medications. It is essential to identify and address the underlying cause of hyperventilation for proper treatment.

Acute Lung Injury (ALI) is a medical condition characterized by inflammation and damage to the lung tissue, which can lead to difficulty breathing and respiratory failure. It is often caused by direct or indirect injury to the lungs, such as pneumonia, sepsis, trauma, or inhalation of harmful substances.

The symptoms of ALI include shortness of breath, rapid breathing, cough, and low oxygen levels in the blood. The condition can progress rapidly and may require mechanical ventilation to support breathing. Treatment typically involves addressing the underlying cause of the injury, providing supportive care, and managing symptoms.

In severe cases, ALI can lead to Acute Respiratory Distress Syndrome (ARDS), a more serious and life-threatening condition that requires intensive care unit (ICU) treatment.

A diaphragm is a thin, dome-shaped muscle that separates the chest cavity from the abdominal cavity. It plays a vital role in the process of breathing as it contracts and flattens to draw air into the lungs (inhalation) and relaxes and returns to its domed shape to expel air out of the lungs (exhalation).

In addition, a diaphragm is also a type of barrier method of birth control. It is a flexible dome-shaped device made of silicone that fits over the cervix inside the vagina. When used correctly and consistently, it prevents sperm from entering the uterus and fertilizing an egg, thereby preventing pregnancy.

In medical terms, pressure is defined as the force applied per unit area on an object or body surface. It is often measured in millimeters of mercury (mmHg) in clinical settings. For example, blood pressure is the force exerted by circulating blood on the walls of the arteries and is recorded as two numbers: systolic pressure (when the heart beats and pushes blood out) and diastolic pressure (when the heart rests between beats).

Pressure can also refer to the pressure exerted on a wound or incision to help control bleeding, or the pressure inside the skull or spinal canal. High or low pressure in different body systems can indicate various medical conditions and require appropriate treatment.

Respiratory physiological phenomena refer to the various mechanical, chemical, and biological processes and functions that occur in the respiratory system during breathing and gas exchange. These phenomena include:

1. Ventilation: The movement of air into and out of the lungs, which is achieved through the contraction and relaxation of the diaphragm and intercostal muscles.
2. Gas Exchange: The diffusion of oxygen (O2) from the alveoli into the bloodstream and carbon dioxide (CO2) from the bloodstream into the alveoli.
3. Respiratory Mechanics: The physical properties and forces that affect the movement of air in and out of the lungs, such as lung compliance, airway resistance, and chest wall elasticity.
4. Control of Breathing: The regulation of ventilation by the central nervous system through the integration of sensory information from chemoreceptors and mechanoreceptors in the respiratory system.
5. Acid-Base Balance: The maintenance of a stable pH level in the blood through the regulation of CO2 elimination and bicarbonate balance by the respiratory and renal systems.
6. Oxygen Transport: The binding of O2 to hemoglobin in the red blood cells and its delivery to the tissues for metabolic processes.
7. Defense Mechanisms: The various protective mechanisms that prevent the entry and colonization of pathogens and foreign particles into the respiratory system, such as mucociliary clearance, cough reflex, and immune responses.

In the context of medicine, and specifically in physiology and respiratory therapy, partial pressure (P or p) is a measure of the pressure exerted by an individual gas in a mixture of gases. It's commonly used to describe the concentrations of gases in the body, such as oxygen (PO2), carbon dioxide (PCO2), and nitrogen (PN2).

The partial pressure of a specific gas is calculated as the fraction of that gas in the total mixture multiplied by the total pressure of the mixture. This concept is based on Dalton's law, which states that the total pressure exerted by a mixture of gases is equal to the sum of the pressures exerted by each individual gas.

For example, in room air at sea level, the partial pressure of oxygen (PO2) is approximately 160 mmHg (mm of mercury), which represents about 21% of the total barometric pressure (760 mmHg). This concept is crucial for understanding gas exchange in the lungs and how gases move across membranes, such as from alveoli to blood and vice versa.

Intubation, intratracheal is a medical procedure in which a flexible plastic or rubber tube called an endotracheal tube (ETT) is inserted through the mouth or nose, passing through the vocal cords and into the trachea (windpipe). This procedure is performed to establish and maintain a patent airway, allowing for the delivery of oxygen and the removal of carbon dioxide during mechanical ventilation in various clinical scenarios, such as:

1. Respiratory failure or arrest
2. Procedural sedation
3. Surgery under general anesthesia
4. Neuromuscular disorders
5. Ingestion of toxic substances
6. Head and neck trauma
7. Critical illness or injury affecting the airway

The process of intubation is typically performed by trained medical professionals, such as anesthesiologists, emergency medicine physicians, or critical care specialists, using direct laryngoscopy or video laryngoscopy to visualize the vocal cords and guide the ETT into the correct position. Once placed, the ETT is secured to prevent dislodgement, and the patient's respiratory status is continuously monitored to ensure proper ventilation and oxygenation.

High-frequency ventilation (HFV) is a specialized mode of mechanical ventilation that delivers breaths at higher rates (usually 120-900 breaths per minute) and smaller tidal volumes (1-3 mL/kg) compared to conventional ventilation. This technique aims to reduce lung injury caused by overdistension and atelectasis, which can occur with traditional ventilator settings. It is often used in neonatal and pediatric intensive care units for the management of severe respiratory distress syndrome, meconium aspiration syndrome, and other conditions where conventional ventilation may be harmful.

There are two main types of high-frequency ventilation: high-frequency oscillatory ventilation (HFOV) and high-frequency jet ventilation (HFJV). Both techniques use different methods to generate the high-frequency breaths but share similar principles in delivering small tidal volumes at rapid rates.

In summary, high-frequency ventilation is a medical intervention that utilizes specialized ventilators to deliver faster and smaller breaths, minimizing lung injury and improving oxygenation for critically ill patients with severe respiratory distress.

Respiratory insufficiency is a condition characterized by the inability of the respiratory system to maintain adequate gas exchange, resulting in an inadequate supply of oxygen and/or removal of carbon dioxide from the body. This can occur due to various causes, such as lung diseases (e.g., chronic obstructive pulmonary disease, pneumonia), neuromuscular disorders (e.g., muscular dystrophy, spinal cord injury), or other medical conditions that affect breathing mechanics and/or gas exchange.

Respiratory insufficiency can manifest as hypoxemia (low oxygen levels in the blood) and/or hypercapnia (high carbon dioxide levels in the blood). Symptoms of respiratory insufficiency may include shortness of breath, rapid breathing, fatigue, confusion, and in severe cases, loss of consciousness or even death. Treatment depends on the underlying cause and severity of the condition and may include oxygen therapy, mechanical ventilation, medications, and/or other supportive measures.

Capnography is the non-invasive measurement and monitoring of carbon dioxide (CO2) in exhaled breath, also known as end-tidal CO2 (EtCO2). It is typically displayed as a waveform graph that shows the concentration of CO2 over time. Capnography provides important information about respiratory function, metabolic rate, and the effectiveness of ventilation during medical procedures such as anesthesia, mechanical ventilation, and resuscitation. Changes in capnograph patterns can help detect conditions such as hypoventilation, hyperventilation, esophageal intubation, and pulmonary embolism.

Ventilator weaning is the process of gradually reducing the amount of support provided by a mechanical ventilator to a patient, with the ultimate goal of completely withdrawing the mechanical assistance and allowing the patient to breathe independently. This process is typically initiated when the patient's underlying medical condition has improved to the point where they are able to sustain their own respiratory efforts.

The weaning process may involve reducing the frequency and duration of ventilator breaths, decreasing the amount of oxygen supplied by the ventilator, or adjusting the settings of the ventilator to encourage the patient to take more frequent and deeper breaths on their own. The rate at which weaning is attempted will depend on the individual patient's condition and overall progress.

Close monitoring of the patient's respiratory status, oxygenation, and work of breathing is essential during the weaning process to ensure that the patient is able to tolerate the decreased level of support and to identify any potential complications that may arise. Effective communication between the healthcare team and the patient is also important to provide education, set expectations, and address any concerns or questions that may arise during the weaning process.

Stroke volume is a term used in cardiovascular physiology and medicine. It refers to the amount of blood that is pumped out of the left ventricle of the heart during each contraction (systole). Specifically, it is the difference between the volume of blood in the left ventricle at the end of diastole (when the ventricle is filled with blood) and the volume at the end of systole (when the ventricle has contracted and ejected its contents into the aorta).

Stroke volume is an important measure of heart function, as it reflects the ability of the heart to pump blood effectively to the rest of the body. A low stroke volume may indicate that the heart is not pumping efficiently, while a high stroke volume may suggest that the heart is working too hard. Stroke volume can be affected by various factors, including heart disease, high blood pressure, and physical fitness level.

The formula for calculating stroke volume is:

Stroke Volume = End-Diastolic Volume - End-Systolic Volume

Where end-diastolic volume (EDV) is the volume of blood in the left ventricle at the end of diastole, and end-systolic volume (ESV) is the volume of blood in the left ventricle at the end of systole.

Pulmonary stretch receptors are nerve endings (receptors) located in the smooth muscle of the airways, specifically within the bronchi and bronchioles of the lungs. They are also known as irritant receptors or slowly adapting receptors. These receptors respond to mechanical deformation caused by lung inflation during breathing. When the lungs stretch, these receptors send signals to the brain via the vagus nerve, which helps regulate breathing patterns and depth. This reflex is known as the Hering-Breuer reflex, which can inhibit inspiration and promote expiration, preventing overinflation of the lungs and helping maintain lung volume within normal ranges.

The thorax is the central part of the human body, located between the neck and the abdomen. In medical terms, it refers to the portion of the body that contains the heart, lungs, and associated structures within a protective cage made up of the sternum (breastbone), ribs, and thoracic vertebrae. The thorax is enclosed by muscles and protected by the ribcage, which helps to maintain its structural integrity and protect the vital organs contained within it.

The thorax plays a crucial role in respiration, as it allows for the expansion and contraction of the lungs during breathing. This movement is facilitated by the flexible nature of the ribcage, which expands and contracts with each breath, allowing air to enter and exit the lungs. Additionally, the thorax serves as a conduit for major blood vessels, such as the aorta and vena cava, which carry blood to and from the heart and the rest of the body.

Understanding the anatomy and function of the thorax is essential for medical professionals, as many conditions and diseases can affect this region of the body. These may include respiratory disorders such as pneumonia or chronic obstructive pulmonary disease (COPD), cardiovascular conditions like heart attacks or aortic aneurysms, and musculoskeletal issues involving the ribs, spine, or surrounding muscles.

Plasma volume refers to the total amount of plasma present in an individual's circulatory system. Plasma is the fluid component of blood, in which cells and chemical components are suspended. It is composed mainly of water, along with various dissolved substances such as nutrients, waste products, hormones, gases, and proteins.

Plasma volume is a crucial factor in maintaining proper blood flow, regulating body temperature, and facilitating the transportation of oxygen, carbon dioxide, and other essential components throughout the body. The average plasma volume for an adult human is approximately 3 liters, but it can vary depending on factors like age, sex, body weight, and overall health status.

Changes in plasma volume can have significant effects on an individual's cardiovascular function and fluid balance. For example, dehydration or blood loss can lead to a decrease in plasma volume, while conditions such as heart failure or liver cirrhosis may result in increased plasma volume due to fluid retention. Accurate measurement of plasma volume is essential for diagnosing various medical conditions and monitoring the effectiveness of treatments.

Pulmonary alveoli, also known as air sacs, are tiny clusters of air-filled pouches located at the end of the bronchioles in the lungs. They play a crucial role in the process of gas exchange during respiration. The thin walls of the alveoli, called alveolar membranes, allow oxygen from inhaled air to pass into the bloodstream and carbon dioxide from the bloodstream to pass into the alveoli to be exhaled out of the body. This vital function enables the lungs to supply oxygen-rich blood to the rest of the body and remove waste products like carbon dioxide.

Inspiratory Capacity (IC) is the maximum volume of air that can be breathed in after a normal expiration. It is the sum of the tidal volume (the amount of air displaced between normal inspiration and expiration during quiet breathing) and the inspiratory reserve volume (the additional amount of air that can be inspired over and above the tidal volume). IC is an important parameter used in pulmonary function testing to assess lung volumes and capacities in patients with respiratory disorders.

Apnea is a medical condition defined as the cessation of breathing for 10 seconds or more. It can occur during sleep (sleep apnea) or while awake (wakeful apnea). There are different types of sleep apnea, including obstructive sleep apnea, central sleep apnea, and complex sleep apnea syndrome. Obstructive sleep apnea occurs when the airway becomes blocked during sleep, while central sleep apnea occurs when the brain fails to signal the muscles to breathe. Complex sleep apnea syndrome, also known as treatment-emergent central sleep apnea, is a combination of obstructive and central sleep apneas. Sleep apnea can lead to various complications, such as fatigue, difficulty concentrating, high blood pressure, heart disease, and stroke.

Forced Expiratory Volume (FEV) is a medical term used to describe the volume of air that can be forcefully exhaled from the lungs in one second. It is often measured during pulmonary function testing to assess lung function and diagnose conditions such as chronic obstructive pulmonary disease (COPD) or asthma.

FEV is typically expressed as a percentage of the Forced Vital Capacity (FVC), which is the total volume of air that can be exhaled from the lungs after taking a deep breath in. The ratio of FEV to FVC is used to determine whether there is obstruction in the airways, with a lower ratio indicating more severe obstruction.

There are different types of FEV measurements, including FEV1 (the volume of air exhaled in one second), FEV25-75 (the average volume of air exhaled during the middle 50% of the FVC maneuver), and FEV0.5 (the volume of air exhaled in half a second). These measurements can provide additional information about lung function and help guide treatment decisions.

Lung diseases refer to a broad category of disorders that affect the lungs and other structures within the respiratory system. These diseases can impair lung function, leading to symptoms such as coughing, shortness of breath, chest pain, and wheezing. They can be categorized into several types based on the underlying cause and nature of the disease process. Some common examples include:

1. Obstructive lung diseases: These are characterized by narrowing or blockage of the airways, making it difficult to breathe out. Examples include chronic obstructive pulmonary disease (COPD), asthma, bronchiectasis, and cystic fibrosis.
2. Restrictive lung diseases: These involve stiffening or scarring of the lungs, which reduces their ability to expand and take in air. Examples include idiopathic pulmonary fibrosis, sarcoidosis, and asbestosis.
3. Infectious lung diseases: These are caused by bacteria, viruses, fungi, or parasites that infect the lungs. Examples include pneumonia, tuberculosis, and influenza.
4. Vascular lung diseases: These affect the blood vessels in the lungs, impairing oxygen exchange. Examples include pulmonary embolism, pulmonary hypertension, and chronic thromboembolic pulmonary hypertension (CTEPH).
5. Neoplastic lung diseases: These involve abnormal growth of cells within the lungs, leading to cancer. Examples include small cell lung cancer, non-small cell lung cancer, and mesothelioma.
6. Other lung diseases: These include interstitial lung diseases, pleural effusions, and rare disorders such as pulmonary alveolar proteinosis and lymphangioleiomyomatosis (LAM).

It is important to note that this list is not exhaustive, and there are many other conditions that can affect the lungs. Proper diagnosis and treatment of lung diseases require consultation with a healthcare professional, such as a pulmonologist or respiratory therapist.

Equipment design, in the medical context, refers to the process of creating and developing medical equipment and devices, such as surgical instruments, diagnostic machines, or assistive technologies. This process involves several stages, including:

1. Identifying user needs and requirements
2. Concept development and brainstorming
3. Prototyping and testing
4. Design for manufacturing and assembly
5. Safety and regulatory compliance
6. Verification and validation
7. Training and support

The goal of equipment design is to create safe, effective, and efficient medical devices that meet the needs of healthcare providers and patients while complying with relevant regulations and standards. The design process typically involves a multidisciplinary team of engineers, clinicians, designers, and researchers who work together to develop innovative solutions that improve patient care and outcomes.

Spirometry is a common type of pulmonary function test (PFT) that measures how well your lungs work. This is done by measuring how much air you can exhale from your lungs after taking a deep breath, and how quickly you can exhale it. The results are compared to normal values for your age, height, sex, and ethnicity.

Spirometry is used to diagnose and monitor certain lung conditions, such as asthma, chronic obstructive pulmonary disease (COPD), and other respiratory diseases that cause narrowing of the airways. It can also be used to assess the effectiveness of treatment for these conditions. The test is non-invasive, safe, and easy to perform.

A vagotomy is a surgical procedure that involves cutting or blocking the vagus nerve, which is a parasympathetic nerve that runs from the brainstem to the abdomen and helps regulate many bodily functions such as heart rate, gastrointestinal motility, and digestion. In particular, vagotomy is often performed as a treatment for peptic ulcers, as it can help reduce gastric acid secretion.

There are several types of vagotomy procedures, including:

1. Truncal vagotomy: This involves cutting the main trunks of the vagus nerve as they enter the abdomen. It is a more extensive procedure that reduces gastric acid secretion significantly but can also lead to side effects such as delayed gastric emptying and diarrhea.
2. Selective vagotomy: This involves cutting only the branches of the vagus nerve that supply the stomach, leaving the rest of the nerve intact. It is a less extensive procedure that reduces gastric acid secretion while minimizing side effects.
3. Highly selective vagotomy (HSV): Also known as parietal cell vagotomy, this involves cutting only the branches of the vagus nerve that supply the acid-secreting cells in the stomach. It is a highly targeted procedure that reduces gastric acid secretion while minimizing side effects such as delayed gastric emptying and diarrhea.

Vagotomy is typically performed using laparoscopic or open surgical techniques, depending on the patient's individual needs and the surgeon's preference. While vagotomy can be effective in treating peptic ulcers, it is not commonly performed today due to the development of less invasive treatments such as proton pump inhibitors (PPIs) that reduce gastric acid secretion without surgery.

Impedance plethysmography is a non-invasive method used to measure changes in blood volume or flow in a particular area of the body. It works by passing a small electrical current through the tissue and measuring the opposition (impedance) to that current, which varies with the amount of blood present in the area.

In impedance cardiography, this technique is used to estimate cardiac output, stroke volume, and other hemodynamic parameters. The changes in impedance are measured across the chest wall, which correlate with the ventricular ejection of blood during each heartbeat. This allows for the calculation of various cardiovascular variables, such as the amount of blood pumped by the heart per minute (cardiac output) and the resistance to blood flow in the systemic circulation (systemic vascular resistance).

Impedance plethysmography is a safe and reliable method for assessing cardiovascular function, and it has been widely used in clinical settings to evaluate patients with various cardiovascular disorders, including heart failure, hypertension, and peripheral arterial disease.

Anesthesia is a medical term that refers to the loss of sensation or awareness, usually induced by the administration of various drugs. It is commonly used during surgical procedures to prevent pain and discomfort. There are several types of anesthesia, including:

1. General anesthesia: This type of anesthesia causes a complete loss of consciousness and is typically used for major surgeries.
2. Regional anesthesia: This type of anesthesia numbs a specific area of the body, such as an arm or leg, while the patient remains conscious.
3. Local anesthesia: This type of anesthesia numbs a small area of the body, such as a cut or wound, and is typically used for minor procedures.

Anesthesia can be administered through various routes, including injection, inhalation, or topical application. The choice of anesthesia depends on several factors, including the type and duration of the procedure, the patient's medical history, and their overall health. Anesthesiologists are medical professionals who specialize in administering anesthesia and monitoring patients during surgical procedures to ensure their safety and comfort.

Exhalation is the act of breathing out or exhaling, which is the reverse process of inhalation. During exhalation, the diaphragm relaxes and moves upwards, while the chest muscles also relax, causing the chest cavity to decrease in size. This decrease in size puts pressure on the lungs, causing them to deflate and expel air.

Exhalation is a passive process that occurs naturally after inhalation, but it can also be actively controlled during activities such as speaking, singing, or playing a wind instrument. In medical terms, exhalation may also be referred to as expiration.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Pulmonary edema is a medical condition characterized by the accumulation of fluid in the alveoli (air sacs) and interstitial spaces (the area surrounding the alveoli) within the lungs. This buildup of fluid can lead to impaired gas exchange, resulting in shortness of breath, coughing, and difficulty breathing, especially when lying down. Pulmonary edema is often a complication of heart failure, but it can also be caused by other conditions such as pneumonia, trauma, or exposure to certain toxins.

In the early stages of pulmonary edema, patients may experience mild symptoms such as shortness of breath during physical activity. However, as the condition progresses, symptoms can become more severe and include:

* Severe shortness of breath, even at rest
* Wheezing or coughing up pink, frothy sputum
* Rapid breathing and heart rate
* Anxiety or restlessness
* Bluish discoloration of the skin (cyanosis) due to lack of oxygen

Pulmonary edema can be diagnosed through a combination of physical examination, medical history, chest X-ray, and other diagnostic tests such as echocardiography or CT scan. Treatment typically involves addressing the underlying cause of the condition, as well as providing supportive care such as supplemental oxygen, diuretics to help remove excess fluid from the body, and medications to help reduce anxiety and improve breathing. In severe cases, mechanical ventilation may be necessary to support respiratory function.

Hemodynamics is the study of how blood flows through the cardiovascular system, including the heart and the vascular network. It examines various factors that affect blood flow, such as blood volume, viscosity, vessel length and diameter, and pressure differences between different parts of the circulatory system. Hemodynamics also considers the impact of various physiological and pathological conditions on these variables, and how they in turn influence the function of vital organs and systems in the body. It is a critical area of study in fields such as cardiology, anesthesiology, and critical care medicine.

General anesthesia is a state of controlled unconsciousness, induced by administering various medications, that eliminates awareness, movement, and pain sensation during medical procedures. It involves the use of a combination of intravenous and inhaled drugs to produce a reversible loss of consciousness, allowing patients to undergo surgical or diagnostic interventions safely and comfortably. The depth and duration of anesthesia are carefully monitored and adjusted throughout the procedure by an anesthesiologist or certified registered nurse anesthetist (CRNA) to ensure patient safety and optimize recovery. General anesthesia is typically used for more extensive surgical procedures, such as open-heart surgery, major orthopedic surgeries, and neurosurgery.

Chemoreceptor cells are specialized sensory neurons that detect and respond to chemical changes in the internal or external environment. They play a crucial role in maintaining homeostasis within the body by converting chemical signals into electrical impulses, which are then transmitted to the central nervous system for further processing and response.

There are two main types of chemoreceptor cells:

1. Oxygen Chemoreceptors: These cells are located in the carotid bodies near the bifurcation of the common carotid artery and in the aortic bodies close to the aortic arch. They monitor the levels of oxygen, carbon dioxide, and pH in the blood and respond to decreases in oxygen concentration or increases in carbon dioxide and hydrogen ions (indicating acidity) by increasing their firing rate. This signals the brain to increase respiratory rate and depth, thereby restoring normal oxygen levels.

2. Taste Cells: These chemoreceptor cells are found within the taste buds of the tongue and other areas of the oral cavity. They detect specific tastes (salty, sour, sweet, bitter, and umami) by interacting with molecules from food. When a tastant binds to receptors on the surface of a taste cell, it triggers a series of intracellular signaling events that ultimately lead to the generation of an action potential. This information is then relayed to the brain, where it is interpreted as taste sensation.

In summary, chemoreceptor cells are essential for maintaining physiological balance by detecting and responding to chemical stimuli in the body. They play a critical role in regulating vital functions such as respiration and digestion.

A manikin is commonly referred to as a full-size model of the human body used for training in various medical and healthcare fields. Medical manikins are often made from materials that simulate human skin and tissues, allowing for realistic practice in procedures such as physical examinations, resuscitation, and surgical techniques.

These manikins can be highly advanced, with built-in mechanisms to simulate physiological responses, such as breathing, heartbeats, and pupil dilation. They may also have interchangeable parts, allowing for the simulation of various medical conditions and scenarios. Medical manikins are essential tools in healthcare education, enabling learners to develop their skills and confidence in a controlled, safe environment before working with real patients.

Dioctyl Sulfosuccinic Acid (DOS) is a type of organic compound that is used as a surfactant and a dispersing agent in various industrial and commercial applications. It is a white to off-white crystalline powder, soluble in water and most organic solvents.

In medical terms, Dioctyl Sulfosuccinic Acid is not commonly used as a therapeutic agent. However, it may be used as an excipient or a component of the formulation in some pharmaceutical products. It has been used as a component in some oral and topical medications to improve their solubility, absorption, and stability.

It is important to note that while Dioctyl Sulfosuccinic Acid itself is not considered harmful, like any other chemical substance, it should be handled with care and used appropriately to avoid any potential health risks.

Total Lung Capacity (TLC) is the maximum volume of air that can be contained within the lungs at the end of a maximal inspiration. It includes all of the following lung volumes: tidal volume, inspiratory reserve volume, expiratory reserve volume, and residual volume. TLC can be measured directly using gas dilution techniques or indirectly by adding residual volume to vital capacity. Factors that affect TLC include age, sex, height, and lung health status.

Expiratory Reserve Volume (ERV) is the maximum amount of air that can be exhaled forcefully after a normal tidal exhalation. It is the difference between the functional residual capacity (FRC) and the residual volume (RV). In other words, ERV is the extra volume of air that can be exhaled from the lungs after a normal breath out, when one tries to empty the lungs as much as possible. This volume is an important parameter in pulmonary function tests and helps assess lung health and disease. A decreased ERV may indicate restrictive lung diseases such as pulmonary fibrosis or neuromuscular disorders affecting respiratory muscles.

Bronchoalveolar lavage (BAL) fluid is a type of clinical specimen obtained through a procedure called bronchoalveolar lavage. This procedure involves inserting a bronchoscope into the lungs and instilling a small amount of saline solution into a specific area of the lung, then gently aspirating the fluid back out. The fluid that is recovered is called bronchoalveolar lavage fluid.

BAL fluid contains cells and other substances that are present in the lower respiratory tract, including the alveoli (the tiny air sacs where gas exchange occurs). By analyzing BAL fluid, doctors can diagnose various lung conditions, such as pneumonia, interstitial lung disease, and lung cancer. They can also monitor the effectiveness of treatments for these conditions by comparing the composition of BAL fluid before and after treatment.

BAL fluid is typically analyzed for its cellular content, including the number and type of white blood cells present, as well as for the presence of bacteria, viruses, or other microorganisms. The fluid may also be tested for various proteins, enzymes, and other biomarkers that can provide additional information about lung health and disease.

Oxygen consumption, also known as oxygen uptake, is the amount of oxygen that is consumed or utilized by the body during a specific period of time, usually measured in liters per minute (L/min). It is a common measurement used in exercise physiology and critical care medicine to assess an individual's aerobic metabolism and overall health status.

In clinical settings, oxygen consumption is often measured during cardiopulmonary exercise testing (CPET) to evaluate cardiovascular function, pulmonary function, and exercise capacity in patients with various medical conditions such as heart failure, chronic obstructive pulmonary disease (COPD), and other respiratory or cardiac disorders.

During exercise, oxygen is consumed by the muscles to generate energy through a process called oxidative phosphorylation. The amount of oxygen consumed during exercise can provide important information about an individual's fitness level, exercise capacity, and overall health status. Additionally, measuring oxygen consumption can help healthcare providers assess the effectiveness of treatments and rehabilitation programs in patients with various medical conditions.

Erythrocyte volume, also known as red cell volume or hematocrit, is the proportion of whole blood that is made up of erythrocytes or red blood cells. It is typically expressed as a percentage and can be measured using a centrifuge to separate the components of a blood sample by density.

The erythrocyte volume is an important clinical parameter because it can provide information about a person's health status, such as their hydration level, altitude acclimatization, and the presence of certain medical conditions like anemia or polycythemia. Changes in erythrocyte volume can also have significant effects on the body's oxygen-carrying capacity and overall cardiovascular function.

Cardiac output is a measure of the amount of blood that is pumped by the heart in one minute. It is defined as the product of stroke volume (the amount of blood pumped by the left ventricle during each contraction) and heart rate (the number of contractions per minute). Normal cardiac output at rest for an average-sized adult is about 5 to 6 liters per minute. Cardiac output can be increased during exercise or other conditions that require more blood flow, such as during illness or injury. It can be measured noninvasively using techniques such as echocardiography or invasively through a catheter placed in the heart.

Vital capacity (VC) is a term used in pulmonary function tests to describe the maximum volume of air that can be exhaled after taking a deep breath. It is the sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume. In other words, it's the total amount of air you can forcibly exhale after inhaling as deeply as possible. Vital capacity is an important measurement in assessing lung function and can be reduced in conditions such as chronic obstructive pulmonary disease (COPD), asthma, and other respiratory disorders.

Sinus arrhythmia is a type of heart rhythm disorder (arrhythmia) where the normal rhythm generated by the sinus node in the heart varies in rate or pattern. The sinus node is the natural pacemaker of the heart and usually sets a steady pace for heartbeats. However, in sinus arrhythmia, the heart rate may speed up or slow down abnormally during breathing in (inspiration) or breathing out (expiration).

When the heart rate increases during inspiration, it is called "inspiratory sinus arrhythmia," and when the heart rate decreases during expiration, it is called "expiratory sinus arrhythmia." Most people experience a mild form of inspiratory sinus arrhythmia, which is considered normal, especially in children and young adults.

However, if the variation in heart rate is significant or accompanied by symptoms such as palpitations, dizziness, shortness of breath, or chest discomfort, it may require medical evaluation and treatment. Sinus arrhythmia can be caused by various factors, including lung disease, heart disease, electrolyte imbalances, or the use of certain medications.

Aerosols are defined in the medical field as suspensions of fine solid or liquid particles in a gas. In the context of public health and medicine, aerosols often refer to particles that can remain suspended in air for long periods of time and can be inhaled. They can contain various substances, such as viruses, bacteria, fungi, or chemicals, and can play a role in the transmission of respiratory infections or other health effects.

For example, when an infected person coughs or sneezes, they may produce respiratory droplets that can contain viruses like influenza or SARS-CoV-2 (the virus that causes COVID-19). Some of these droplets can evaporate quickly and leave behind smaller particles called aerosols, which can remain suspended in the air for hours and potentially be inhaled by others. This is one way that respiratory viruses can spread between people in close proximity to each other.

Aerosols can also be generated through medical procedures such as bronchoscopy, suctioning, or nebulizer treatments, which can produce aerosols containing bacteria, viruses, or other particles that may pose an infection risk to healthcare workers or other patients. Therefore, appropriate personal protective equipment (PPE) and airborne precautions are often necessary to reduce the risk of transmission in these settings.

Pulmonary surfactants are a complex mixture of lipids and proteins that are produced by the alveolar type II cells in the lungs. They play a crucial role in reducing the surface tension at the air-liquid interface within the alveoli, which helps to prevent collapse of the lungs during expiration. Surfactants also have important immunological functions, such as inhibiting the growth of certain bacteria and modulating the immune response. Deficiency or dysfunction of pulmonary surfactants can lead to respiratory distress syndrome (RDS) in premature infants and other lung diseases.

Anoxia is a medical condition that refers to the absence or complete lack of oxygen supply in the body or a specific organ, tissue, or cell. This can lead to serious health consequences, including damage or death of cells and tissues, due to the vital role that oxygen plays in supporting cellular metabolism and energy production.

Anoxia can occur due to various reasons, such as respiratory failure, cardiac arrest, severe blood loss, carbon monoxide poisoning, or high altitude exposure. Prolonged anoxia can result in hypoxic-ischemic encephalopathy, a serious condition that can cause brain damage and long-term neurological impairments.

Medical professionals use various diagnostic tests, such as blood gas analysis, pulse oximetry, and electroencephalography (EEG), to assess oxygen levels in the body and diagnose anoxia. Treatment for anoxia typically involves addressing the underlying cause, providing supplemental oxygen, and supporting vital functions, such as breathing and circulation, to prevent further damage.

The phrenic nerve is a motor nerve that originates from the cervical spine (C3-C5) and descends through the neck to reach the diaphragm, which is the primary muscle used for breathing. The main function of the phrenic nerve is to innervate the diaphragm and control its contraction and relaxation, thereby enabling respiration.

Damage or injury to the phrenic nerve can result in paralysis of the diaphragm, leading to difficulty breathing and potentially causing respiratory failure. Certain medical conditions, such as neuromuscular disorders, spinal cord injuries, and tumors, can affect the phrenic nerve and impair its function.

The thoracic wall refers to the anatomical structure that surrounds and protects the chest cavity or thorax, which contains the lungs, heart, and other vital organs. It is composed of several components:

1. Skeletal framework: This includes the 12 pairs of ribs, the sternum (breastbone) in the front, and the thoracic vertebrae in the back. The upper seven pairs of ribs are directly attached to the sternum in the front through costal cartilages. The lower five pairs of ribs are not directly connected to the sternum but are joined to the ribs above them.
2. Muscles: The thoracic wall contains several muscles, including the intercostal muscles (located between the ribs), the scalene muscles (at the side and back of the neck), and the serratus anterior muscle (on the sides of the chest). These muscles help in breathing by expanding and contracting the ribcage.
3. Soft tissues: The thoracic wall also contains various soft tissues, such as fascia, nerves, blood vessels, and fat. These structures support the functioning of the thoracic organs and contribute to the overall stability and protection of the chest cavity.

The primary function of the thoracic wall is to protect the vital organs within the chest cavity while allowing for adequate movement during respiration. Additionally, it provides a stable base for the attachment of various muscles involved in upper limb movement and posture.

Obstructive lung disease is a category of respiratory diseases characterized by airflow limitation that causes difficulty in completely emptying the alveoli (tiny air sacs) of the lungs during exhaling. This results in the trapping of stale air and prevents fresh air from entering the alveoli, leading to various symptoms such as coughing, wheezing, shortness of breath, and decreased exercise tolerance.

The most common obstructive lung diseases include:

1. Chronic Obstructive Pulmonary Disease (COPD): A progressive disease that includes chronic bronchitis and emphysema, often caused by smoking or exposure to harmful pollutants.
2. Asthma: A chronic inflammatory disorder of the airways characterized by variable airflow obstruction, bronchial hyperresponsiveness, and an underlying inflammation. Symptoms can be triggered by various factors such as allergens, irritants, or physical activity.
3. Bronchiectasis: A condition in which the airways become abnormally widened, scarred, and thickened due to chronic inflammation or infection, leading to mucus buildup and impaired clearance.
4. Cystic Fibrosis: An inherited genetic disorder that affects the exocrine glands, resulting in thick and sticky mucus production in various organs, including the lungs. This can lead to chronic lung infections, inflammation, and airway obstruction.
5. Alpha-1 Antitrypsin Deficiency: A genetic condition characterized by low levels of alpha-1 antitrypsin protein, which leads to uncontrolled protease enzyme activity that damages the lung tissue, causing emphysema-like symptoms.

Treatment for obstructive lung diseases typically involves bronchodilators (to relax and widen the airways), corticosteroids (to reduce inflammation), and lifestyle modifications such as smoking cessation and pulmonary rehabilitation programs. In severe cases, oxygen therapy or even lung transplantation may be considered.

Blood volume determination is a medical procedure that involves measuring the total amount of blood present in an individual's circulatory system. This measurement is typically expressed in milliliters (mL) or liters (L) and provides important information about the person's overall cardiovascular health and fluid status.

There are several methods for determining blood volume, including:

1. Direct measurement: This involves withdrawing a known volume of blood from the body, labeling the red blood cells with a radioactive or dye marker, reinfusing the cells back into the body, and then measuring the amount of marked cells that appear in subsequent blood samples over time.
2. Indirect measurement: This method uses formulas based on the person's height, weight, sex, and other factors to estimate their blood volume. One common indirect method is the "hemodynamic" calculation, which takes into account the individual's heart rate, stroke volume (the amount of blood pumped by the heart with each beat), and the concentration of hemoglobin in their red blood cells.
3. Bioimpedance analysis: This non-invasive technique uses electrical signals to measure the body's fluid volumes, including blood volume. By analyzing changes in the body's electrical conductivity in response to a small current, bioimpedance analysis can provide an estimate of blood volume.

Accurate determination of blood volume is important for assessing various medical conditions, such as heart failure, shock, anemia, and dehydration. It can also help guide treatment decisions, including the need for fluid replacement or blood transfusions.

Helium is not a medical term, but it's a chemical element with symbol He and atomic number 2. It's a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gases section of the periodic table. In medicine, helium is sometimes used in medical settings for its unique properties, such as being less dense than air, which can help improve the delivery of oxygen to patients with respiratory conditions. For example, heliox, a mixture of helium and oxygen, may be used to reduce the work of breathing in patients with conditions like chronic obstructive pulmonary disease (COPD) or asthma. Additionally, helium is also used in cryogenic medical equipment and in magnetic resonance imaging (MRI) machines to cool the superconducting magnets.

Respiratory-gated imaging techniques are medical imaging procedures that synchronize the data acquisition with the patient's respiratory cycle, in order to reduce motion artifacts and improve image quality. These techniques are often used in CT (computed tomography) and MR (magnetic resonance) imaging for thoracic and abdominal examinations, where respiratory motion can degrade the images and compromise diagnostic accuracy.

In a respiratory-gated imaging technique, the patient's breathing pattern is monitored using sensors such as pressure belts or navigators, which detect the movement of the diaphragm or chest wall. The imaging data are then acquired only during specific phases of the respiratory cycle, typically during the end-expiration phase when motion is minimal. This allows for the creation of sharp and detailed images that accurately represent the anatomy and pathology of interest.

Respiratory gating can be particularly useful in imaging patients with lung cancer, liver tumors, or other conditions that involve moving structures in the chest and abdomen. By reducing motion artifacts, these techniques can help ensure more accurate diagnosis, staging, and treatment planning.

A laryngeal mask is a type of supraglottic airway device that is used in anesthesia and critical care to secure the airway during procedures or respiratory support. It consists of an inflatable cuff that is inserted into the hypopharynx, behind the tongue, and above the laryngeal opening. The cuff forms a low-pressure seal around the laryngeal inlet, allowing for the delivery of ventilated gases to the lungs while minimizing the risk of aspiration.

Laryngeal masks are often used as an alternative to endotracheal intubation, especially in cases where intubation is difficult or contraindicated. They are also used in emergency situations for airway management and during resuscitation efforts. Laryngeal masks come in various sizes and designs, with some models allowing for the placement of a gastric tube to decompress the stomach and reduce the risk of regurgitation and aspiration.

Overall, laryngeal masks provide a safe and effective means of securing the airway while minimizing trauma and discomfort to the patient.

Bronchoconstrictor agents are substances that cause narrowing or constriction of the bronchioles, the small airways in the lungs. This can lead to symptoms such as wheezing, coughing, and shortness of breath. Bronchoconstrictor agents include certain medications (such as some beta-blockers and prostaglandin F2alpha), environmental pollutants (such as tobacco smoke and air pollution particles), and allergens (such as dust mites and pollen).

In contrast to bronchodilator agents, which are medications that widen the airways and improve breathing, bronchoconstrictor agents can make it more difficult for a person to breathe. People with respiratory conditions such as asthma or chronic obstructive pulmonary disease (COPD) may be particularly sensitive to bronchoconstrictor agents and may experience severe symptoms when exposed to them.

Interactive Ventilatory Support (IVS) is not a widely recognized or established medical term with a universally accepted definition. However, in the context of mechanical ventilation, it generally refers to a mode of support that allows for some level of interaction between the patient's own breathing efforts and the ventilator's assistance.

One example of IVS is called "Pressure Regulated Volume Control with Automatic Tube Compensation" (PRVC-ATC). In this mode, the ventilator delivers a preset volume while adjusting the pressure to maintain a constant flow, and it compensates for the resistance of the endotracheal tube. The patient's spontaneous breaths are assisted by a lower level of pressure, allowing for some interaction between the patient's efforts and the ventilator's support.

It is important to note that different manufacturers may use the term "Interactive Ventilatory Support" or similar terms to describe various modes or functions of their mechanical ventilators. Therefore, it is always recommended to refer to the specific definitions provided by the manufacturer's user manual or clinical literature.

Analog-digital conversion, also known as analog-to-digital conversion (ADC) or digitization, is the process of converting a continuous physical quantity or analog signal into a discrete numerical representation or digital signal. This process typically involves sampling the analog signal at regular intervals and then quantizing each sample by assigning it to a specific numerical value within a range. The resulting digital signal can be processed, stored, and transmitted more easily than an analog signal. In medical settings, this type of conversion is often used in devices such as electrocardiograms (ECGs) and blood pressure monitors to convert physiological signals into digital data that can be analyzed and interpreted by healthcare professionals.

Heart rate is the number of heartbeats per unit of time, often expressed as beats per minute (bpm). It can vary significantly depending on factors such as age, physical fitness, emotions, and overall health status. A resting heart rate between 60-100 bpm is generally considered normal for adults, but athletes and individuals with high levels of physical fitness may have a resting heart rate below 60 bpm due to their enhanced cardiovascular efficiency. Monitoring heart rate can provide valuable insights into an individual's health status, exercise intensity, and response to various treatments or interventions.

Resuscitation is a medical term that refers to the process of reversing cardiopulmonary arrest or preventing further deterioration of someone in cardiac or respiratory arrest. It involves a series of interventions aimed at restoring spontaneous blood circulation and breathing, thereby preventing or minimizing tissue damage due to lack of oxygen.

The most common form of resuscitation is cardiopulmonary resuscitation (CPR), which combines chest compressions to manually pump blood through the body with rescue breaths to provide oxygen to the lungs. In a hospital setting, more advanced techniques such as defibrillation, medication administration, and intubation may also be used as part of the resuscitation process.

The goal of resuscitation is to stabilize the patient's condition and prevent further harm while treating the underlying cause of the arrest. Successful resuscitation can lead to a full recovery or, in some cases, result in varying degrees of neurological impairment depending on the severity and duration of the cardiac or respiratory arrest.

Bronchoconstriction is a medical term that refers to the narrowing of the airways in the lungs (the bronchi and bronchioles) due to the contraction of the smooth muscles surrounding them. This constriction can cause difficulty breathing, wheezing, coughing, and shortness of breath, which are common symptoms of asthma and other respiratory conditions.

Bronchoconstriction can be triggered by a variety of factors, including allergens, irritants, cold air, exercise, and emotional stress. In some cases, it may also be caused by certain medications, such as beta-blockers or nonsteroidal anti-inflammatory drugs (NSAIDs). Treatment for bronchoconstriction typically involves the use of bronchodilators, which are medications that help to relax the smooth muscles around the airways and widen them, making it easier to breathe.

Neonatology is a subspecialty of pediatrics that focuses on the medical care of newborn infants, particularly those who are born prematurely or with critical illnesses. Neonatologists are physicians who have additional training and expertise in managing complex neonatal conditions such as respiratory distress syndrome, birth defects, infection, and other issues that can affect newborns. They typically work in neonatal intensive care units (NICUs) and collaborate with a multidisciplinary team of healthcare professionals to provide comprehensive care for these vulnerable patients.

Respiratory paralysis is a condition characterized by the inability to breathe effectively due to the failure or weakness of the muscles involved in respiration. This can include the diaphragm, intercostal muscles, and other accessory muscles.

In medical terms, it's often associated with conditions that affect the neuromuscular junction, such as botulism, myasthenia gravis, or spinal cord injuries. It can also occur as a complication of general anesthesia, sedative drugs, or certain types of poisoning.

Respiratory paralysis is a serious condition that requires immediate medical attention, as it can lead to lack of oxygen (hypoxia) and buildup of carbon dioxide (hypercapnia) in the body, which can be life-threatening if not treated promptly.

Forced expiratory flow rates (FEFR) are measures of how quickly and efficiently air can be exhaled from the lungs during a forced breath maneuver. These measurements are often used in pulmonary function testing to help diagnose and monitor obstructive lung diseases such as asthma or chronic obstructive pulmonary disease (COPD).

FEFR is typically measured during a forced expiratory maneuver, where the person takes a deep breath in and then exhales as forcefully and quickly as possible into a mouthpiece connected to a spirometer. The spirometer measures the volume and flow rate of the exhaled air over time.

There are several different FEFR measurements that can be reported, including:

* Forced Expiratory Flow (FEF) 25-75%: This is the average flow rate during the middle half of the forced expiratory maneuver.
* Peak Expiratory Flow Rate (PEFR): This is the maximum flow rate achieved during the first second of the forced expiratory maneuver.
* Forced Expiratory Volume in 1 Second (FEV1): This is the volume of air exhaled in the first second of the forced expiratory maneuver.

Abnormal FEFR values can indicate obstruction in the small airways of the lungs, which can make it difficult to breathe out fully and quickly. The specific pattern of abnormalities in FEFR measurements can help doctors differentiate between different types of obstructive lung diseases.

Intermittent Positive-Pressure Ventilation (IPPV) is a type of mechanical ventilation in which positive pressure is intermittently applied to the airway and lungs, allowing for inflation and deflation of the lungs. This mode of ventilation is often used in critical care settings such as intensive care units (ICUs) to support patients who are unable to breathe effectively on their own due to respiratory failure or other conditions that affect breathing.

During IPPV, a mechanical ventilator delivers breaths to the patient at set intervals, with each breath consisting of a set volume or pressure. The patient may also be allowed to take spontaneous breaths between the mechanically delivered breaths. The settings for IPPV can be adjusted based on the patient's needs and condition, including factors such as their respiratory rate, tidal volume (the amount of air moved with each breath), and positive end-expiratory pressure (PEEP), which helps to keep the alveoli open and prevent atelectasis.

IPPV can be used to provide short-term or long-term ventilatory support, depending on the patient's needs. It is an effective way to ensure that patients receive adequate oxygenation and ventilation while minimizing the risk of lung injury associated with high pressures or volumes. However, it is important to closely monitor patients receiving IPPV and adjust the settings as needed to avoid complications such as ventilator-associated pneumonia or barotrauma.

Anatomic models are three-dimensional representations of body structures used for educational, training, or demonstration purposes. They can be made from various materials such as plastic, wax, or rubber and may depict the entire body or specific regions, organs, or systems. These models can be used to provide a visual aid for understanding anatomy, physiology, and pathology, and can be particularly useful in situations where actual human specimens are not available or practical to use. They may also be used for surgical planning and rehearsal, as well as in medical research and product development.

Blood pressure is the force exerted by circulating blood on the walls of the blood vessels. It is measured in millimeters of mercury (mmHg) and is given as two figures:

1. Systolic pressure: This is the pressure when the heart pushes blood out into the arteries.
2. Diastolic pressure: This is the pressure when the heart rests between beats, allowing it to fill with blood.

Normal blood pressure for adults is typically around 120/80 mmHg, although this can vary slightly depending on age, sex, and other factors. High blood pressure (hypertension) is generally considered to be a reading of 130/80 mmHg or higher, while low blood pressure (hypotension) is usually defined as a reading below 90/60 mmHg. It's important to note that blood pressure can fluctuate throughout the day and may be affected by factors such as stress, physical activity, and medication use.

Medical Definition:

Magnetic Resonance Imaging (MRI) is a non-invasive diagnostic imaging technique that uses a strong magnetic field and radio waves to create detailed cross-sectional or three-dimensional images of the internal structures of the body. The patient lies within a large, cylindrical magnet, and the scanner detects changes in the direction of the magnetic field caused by protons in the body. These changes are then converted into detailed images that help medical professionals to diagnose and monitor various medical conditions, such as tumors, injuries, or diseases affecting the brain, spinal cord, heart, blood vessels, joints, and other internal organs. MRI does not use radiation like computed tomography (CT) scans.

The prone position is a body posture in which an individual lies on their stomach, with their face down and chest facing the floor or bed. This position is often used in medical settings for various purposes, such as during certain surgical procedures, respiratory support, or to alleviate pressure ulcers. It's also important to note that the prone position can have implications for patient safety, particularly in critically ill patients, and should be carefully monitored.

Pulmonary atelectasis is a medical condition characterized by the collapse or closure of the alveoli (tiny air sacs) in the lungs, leading to reduced or absent gas exchange in the affected area. This results in decreased lung volume and can cause hypoxemia (low oxygen levels in the blood). Atelectasis can be caused by various factors such as obstruction of the airways, surfactant deficiency, pneumothorax, or compression from outside the lung. It can also occur after surgical procedures, particularly when the patient is lying in one position for a long time. Symptoms may include shortness of breath, cough, and chest discomfort, but sometimes it may not cause any symptoms, especially if only a small area of the lung is affected. Treatment depends on the underlying cause and may include bronchodilators, chest physiotherapy, or even surgery in severe cases.

Reproducibility of results in a medical context refers to the ability to obtain consistent and comparable findings when a particular experiment or study is repeated, either by the same researcher or by different researchers, following the same experimental protocol. It is an essential principle in scientific research that helps to ensure the validity and reliability of research findings.

In medical research, reproducibility of results is crucial for establishing the effectiveness and safety of new treatments, interventions, or diagnostic tools. It involves conducting well-designed studies with adequate sample sizes, appropriate statistical analyses, and transparent reporting of methods and findings to allow other researchers to replicate the study and confirm or refute the results.

The lack of reproducibility in medical research has become a significant concern in recent years, as several high-profile studies have failed to produce consistent findings when replicated by other researchers. This has led to increased scrutiny of research practices and a call for greater transparency, rigor, and standardization in the conduct and reporting of medical research.

Three-dimensional (3D) imaging in medicine refers to the use of technologies and techniques that generate a 3D representation of internal body structures, organs, or tissues. This is achieved by acquiring and processing data from various imaging modalities such as X-ray computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, or confocal microscopy. The resulting 3D images offer a more detailed visualization of the anatomy and pathology compared to traditional 2D imaging techniques, allowing for improved diagnostic accuracy, surgical planning, and minimally invasive interventions.

In 3D imaging, specialized software is used to reconstruct the acquired data into a volumetric model, which can be manipulated and viewed from different angles and perspectives. This enables healthcare professionals to better understand complex anatomical relationships, detect abnormalities, assess disease progression, and monitor treatment response. Common applications of 3D imaging include neuroimaging, orthopedic surgery planning, cancer staging, dental and maxillofacial reconstruction, and interventional radiology procedures.

The abdomen refers to the portion of the body that lies between the thorax (chest) and the pelvis. It is a musculo-fascial cavity containing the digestive, urinary, and reproductive organs. The abdominal cavity is divided into several regions and quadrants for medical description and examination purposes. These include the upper and lower abdomen, as well as nine quadrants formed by the intersection of the midline and a horizontal line drawn at the level of the umbilicus (navel).

The major organs located within the abdominal cavity include:

1. Stomach - muscular organ responsible for initial digestion of food
2. Small intestine - long, coiled tube where most nutrient absorption occurs
3. Large intestine - consists of the colon and rectum; absorbs water and stores waste products
4. Liver - largest internal organ, involved in protein synthesis, detoxification, and metabolism
5. Pancreas - secretes digestive enzymes and hormones such as insulin
6. Spleen - filters blood and removes old red blood cells
7. Kidneys - pair of organs responsible for filtering waste products from the blood and producing urine
8. Adrenal glands - sit atop each kidney, produce hormones that regulate metabolism, immune response, and stress response

The abdomen is an essential part of the human body, playing a crucial role in digestion, absorption, and elimination of food and waste materials, as well as various metabolic processes.

Analysis of Variance (ANOVA) is a statistical technique used to compare the means of two or more groups and determine whether there are any significant differences between them. It is a way to analyze the variance in a dataset to determine whether the variability between groups is greater than the variability within groups, which can indicate that the groups are significantly different from one another.

ANOVA is based on the concept of partitioning the total variance in a dataset into two components: variance due to differences between group means (also known as "between-group variance") and variance due to differences within each group (also known as "within-group variance"). By comparing these two sources of variance, ANOVA can help researchers determine whether any observed differences between groups are statistically significant, or whether they could have occurred by chance.

ANOVA is a widely used technique in many areas of research, including biology, psychology, engineering, and business. It is often used to compare the means of two or more experimental groups, such as a treatment group and a control group, to determine whether the treatment had a significant effect. ANOVA can also be used to compare the means of different populations or subgroups within a population, to identify any differences that may exist between them.

The vagus nerve, also known as the 10th cranial nerve (CN X), is the longest of the cranial nerves and extends from the brainstem to the abdomen. It has both sensory and motor functions and plays a crucial role in regulating various bodily functions such as heart rate, digestion, respiratory rate, speech, and sweating, among others.

The vagus nerve is responsible for carrying sensory information from the internal organs to the brain, and it also sends motor signals from the brain to the muscles of the throat and voice box, as well as to the heart, lungs, and digestive tract. The vagus nerve helps regulate the body's involuntary responses, such as controlling heart rate and blood pressure, promoting relaxation, and reducing inflammation.

Dysfunction in the vagus nerve can lead to various medical conditions, including gastroparesis, chronic pain, and autonomic nervous system disorders. Vagus nerve stimulation (VNS) is a therapeutic intervention that involves delivering electrical impulses to the vagus nerve to treat conditions such as epilepsy, depression, and migraine headaches.

I believe there might be a misunderstanding in your question. "Dogs" is not a medical term or condition. It is the common name for a domesticated carnivore of the family Canidae, specifically the genus Canis, which includes wolves, foxes, and other extant and extinct species of mammals. Dogs are often kept as pets and companions, and they have been bred in a wide variety of forms and sizes for different purposes, such as hunting, herding, guarding, assisting police and military forces, and providing companionship and emotional support.

If you meant to ask about a specific medical condition or term related to dogs, please provide more context so I can give you an accurate answer.

Airway obstruction is a medical condition that occurs when the normal flow of air into and out of the lungs is partially or completely blocked. This blockage can be caused by a variety of factors, including swelling of the tissues in the airway, the presence of foreign objects or substances, or abnormal growths such as tumors.

When the airway becomes obstructed, it can make it difficult for a person to breathe normally. They may experience symptoms such as shortness of breath, wheezing, coughing, and chest tightness. In severe cases, airway obstruction can lead to respiratory failure and other life-threatening complications.

There are several types of airway obstruction, including:

1. Upper airway obstruction: This occurs when the blockage is located in the upper part of the airway, such as the nose, throat, or voice box.
2. Lower airway obstruction: This occurs when the blockage is located in the lower part of the airway, such as the trachea or bronchi.
3. Partial airway obstruction: This occurs when the airway is partially blocked, allowing some air to flow in and out of the lungs.
4. Complete airway obstruction: This occurs when the airway is completely blocked, preventing any air from flowing into or out of the lungs.

Treatment for airway obstruction depends on the underlying cause of the condition. In some cases, removing the obstruction may be as simple as clearing the airway of foreign objects or mucus. In other cases, more invasive treatments such as surgery may be necessary.

Organ size refers to the volume or physical measurement of an organ in the body of an individual. It can be described in terms of length, width, and height or by using specialized techniques such as imaging studies (like CT scans or MRIs) to determine the volume. The size of an organ can vary depending on factors such as age, sex, body size, and overall health status. Changes in organ size may indicate various medical conditions, including growths, inflammation, or atrophy.

A tracheotomy is a surgical procedure that involves creating an opening in the neck and through the front (anterior) wall of the trachea (windpipe). This is performed to provide a new airway for the patient, bypassing any obstruction or damage in the upper airways. A tube is then inserted into this opening to maintain it and allow breathing.

This procedure is often conducted in emergency situations when there is an upper airway obstruction that cannot be easily removed or in critically ill patients who require long-term ventilation support. Complications can include infection, bleeding, damage to surrounding structures, and difficulties with speaking, swallowing, or coughing.

Intermittent Positive-Pressure Breathing (IPPB) is a type of ventilatory support that involves the intermittent delivery of positive pressure to the airways and alveoli during inspiration, while allowing for expiration to occur passively. This technique is often used in medical settings to assist patients with respiratory insufficiency or failure, such as those with chronic obstructive pulmonary disease (COPD), neuromuscular disorders, or following surgery.

During IPPB, the patient breathes in through a mouthpiece or mask that is connected to a ventilator or breathing machine. The machine delivers positive pressure to the airways, which helps to inflate the lungs and improve oxygenation. The pressure can be adjusted to meet the needs of each individual patient, and the frequency and duration of breaths can also be controlled by the healthcare provider.

IPPB is typically used on a short-term basis, as a means of providing respiratory support while a patient's underlying condition improves. It may be used in conjunction with other therapies, such as bronchodilators or corticosteroids, to help improve lung function and reduce symptoms. While IPPB can be an effective tool for managing respiratory insufficiency, it is not without risks, and careful monitoring is required to ensure that it is used safely and effectively.

The abdominal muscles, also known as the abdominals or abs, are a group of muscles in the anterior (front) wall of the abdominopelvic cavity. They play a crucial role in maintaining posture, supporting the trunk, and facilitating movement of the torso. The main abdominal muscles include:

1. Rectus Abdominis: These are the pair of long, flat muscles that run vertically along the middle of the anterior abdominal wall. They are often referred to as the "six-pack" muscles due to their visible, segmented appearance in well-trained individuals. The primary function of the rectus abdominis is to flex the spine, allowing for actions such as sitting up from a lying down position or performing a crunch exercise.

2. External Obliques: These are the largest and most superficial of the oblique muscles, located on the lateral (side) aspects of the abdominal wall. They run diagonally downward and forward from the lower ribs to the iliac crest (the upper part of the pelvis) and the pubic tubercle (a bony prominence at the front of the pelvis). The external obliques help rotate and flex the trunk, as well as assist in side-bending and exhalation.

3. Internal Obliques: These muscles lie deep to the external obliques and run diagonally downward and backward from the lower ribs to the iliac crest, pubic tubercle, and linea alba (the strong band of connective tissue that runs vertically along the midline of the abdomen). The internal obliques help rotate and flex the trunk, as well as assist in forced exhalation and increasing intra-abdominal pressure during actions such as coughing or lifting heavy objects.

4. Transversus Abdominis: This is the deepest of the abdominal muscles, located inner to both the internal obliques and the rectus sheath (a strong, fibrous covering that surrounds the rectus abdominis). The transversus abdominis runs horizontally around the abdomen, attaching to the lower six ribs, the thoracolumbar fascia (a broad sheet of connective tissue spanning from the lower back to the pelvis), and the pubic crest (the front part of the pelvic bone). The transversus abdominis helps maintain core stability by compressing the abdominal contents and increasing intra-abdominal pressure.

Together, these muscles form the muscular "corset" of the abdomen, providing support, stability, and flexibility to the trunk. They also play a crucial role in respiration, posture, and various movements such as bending, twisting, and lifting.

Liquid ventilation is a medical procedure that involves the use of an oxygen-rich liquid, such as perfluorocarbons (PFCs), to replace air in the lungs. This technique is used to improve gas exchange and lung function in patients with severe respiratory distress syndrome (RDS) or other forms of acute lung injury.

During liquid ventilation, the liquid is instilled into the lungs through a special endotracheal tube, causing the alveoli (tiny air sacs in the lungs) to fill up and float in the liquid. The PFCs used in liquid ventilation are capable of dissolving large amounts of oxygen and carbon dioxide, allowing for efficient gas exchange between the lungs and the bloodstream.

The use of liquid ventilation has been shown to improve lung compliance, reduce lung injury, and decrease the need for mechanical ventilation in some patients with severe respiratory distress. However, further research is needed to fully understand its potential benefits and risks.

Intrinsic Positive-Pressure Respiration (IPPR) is a type of positive-pressure breathing that occurs naturally within the body, without the use of mechanical ventilation or other external devices. It is also known as "auto-PEEP" or "occult PEEP," where PEEP stands for Positive End-Expiratory Pressure.

In normal, spontaneous breathing, the pressure inside the alveoli (air sacs) in the lungs becomes slightly negative during inhalation and returns to atmospheric pressure during exhalation. However, certain lung conditions or patient efforts can lead to an increase in resistance to airflow during exhalation, causing positive pressure to persist within the alveoli at the end of expiration. This results in intrinsic PEEP or auto-PEEP.

IPPR can be caused by several factors, including:

1. Air trapping due to obstructive lung diseases like chronic obstructive pulmonary disease (COPD) or asthma
2. High respiratory rates leading to incomplete exhalation before the next inspiration begins
3. Inadequate expiratory time, often seen in mechanically ventilated patients with high tidal volumes and/or low respiratory rates
4. Dynamic hyperinflation due to increased minute ventilation or high inspiratory flow rates
5. Bronchoconstriction or airway narrowing, which can occur during an asthma attack or in certain other lung conditions

IPPR has several clinical implications, such as reduced venous return and cardiac output, increased work of breathing, and potential for lung injury due to overdistension (volutrauma). Healthcare providers must consider IPPR when managing patients with respiratory distress, especially those on mechanical ventilation, to optimize their care and prevent complications.

Methacholine chloride is a medication that is used as a diagnostic tool to help identify and assess the severity of asthma or other respiratory conditions that cause airway hyperresponsiveness. It is a synthetic derivative of acetylcholine, which is a neurotransmitter that causes smooth muscle contraction in the body.

When methacholine chloride is inhaled, it stimulates the muscarinic receptors in the airways, causing them to constrict or narrow. This response is measured and used to determine the degree of airway hyperresponsiveness, which can help diagnose asthma and assess its severity.

The methacholine challenge test involves inhaling progressively higher doses of methacholine chloride until a significant decrease in lung function is observed or until a maximum dose is reached. The test results are then used to guide treatment decisions and monitor the effectiveness of therapy. It's important to note that this test should be conducted under the supervision of a healthcare professional, as it carries some risks, including bronchoconstriction and respiratory distress.

Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.

Examples of biological models include:

1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.

Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.

Respiratory Distress Syndrome (RDS), Newborn is a common lung disorder in premature infants. It occurs when the lungs lack a substance called surfactant, which helps keep the tiny air sacs in the lungs open. This results in difficulty breathing and oxygenation, causing symptoms such as rapid, shallow breathing, grunting noises, flaring of the nostrils, and retractions (the skin between the ribs pulls in with each breath). RDS is more common in infants born before 34 weeks of gestation and is treated with surfactant replacement therapy, oxygen support, and mechanical ventilation if necessary. In severe cases, it can lead to complications such as bronchopulmonary dysplasia or even death.

Pulmonary circulation refers to the process of blood flow through the lungs, where blood picks up oxygen and releases carbon dioxide. This is a vital part of the overall circulatory system, which delivers nutrients and oxygen to the body's cells while removing waste products like carbon dioxide.

In pulmonary circulation, deoxygenated blood from the systemic circulation returns to the right atrium of the heart via the superior and inferior vena cava. The blood then moves into the right ventricle through the tricuspid valve and gets pumped into the pulmonary artery when the right ventricle contracts.

The pulmonary artery divides into smaller vessels called arterioles, which further branch into a vast network of tiny capillaries in the lungs. Here, oxygen from the alveoli diffuses into the blood, binding to hemoglobin in red blood cells, while carbon dioxide leaves the blood and is exhaled through the nose or mouth.

The now oxygenated blood collects in venules, which merge to form pulmonary veins. These veins transport the oxygen-rich blood back to the left atrium of the heart, where it enters the systemic circulation once again. This continuous cycle enables the body's cells to receive the necessary oxygen and nutrients for proper functioning while disposing of waste products.

Physiological monitoring is the continuous or intermittent observation and measurement of various body functions or parameters in a patient, with the aim of evaluating their health status, identifying any abnormalities or changes, and guiding clinical decision-making and treatment. This may involve the use of specialized medical equipment, such as cardiac monitors, pulse oximeters, blood pressure monitors, and capnographs, among others. The data collected through physiological monitoring can help healthcare professionals assess the effectiveness of treatments, detect complications early, and make timely adjustments to patient care plans.

Prospective studies, also known as longitudinal studies, are a type of cohort study in which data is collected forward in time, following a group of individuals who share a common characteristic or exposure over a period of time. The researchers clearly define the study population and exposure of interest at the beginning of the study and follow up with the participants to determine the outcomes that develop over time. This type of study design allows for the investigation of causal relationships between exposures and outcomes, as well as the identification of risk factors and the estimation of disease incidence rates. Prospective studies are particularly useful in epidemiology and medical research when studying diseases with long latency periods or rare outcomes.

Nebulizer: A nebulizer is a medical device that delivers medication in the form of a mist to the respiratory system. It is often used for people who have difficulty inhaling medication through traditional inhalers, such as young children or individuals with severe respiratory conditions. The medication is placed in the nebulizer cup and then converted into a fine mist by the machine. This allows the user to breathe in the medication directly through a mouthpiece or mask.

Vaporizer: A vaporizer, on the other hand, is a device that heats up a liquid, often water or essential oils, to produce steam or vapor. While some people use vaporizers for therapeutic purposes, such as to help relieve congestion or cough, it is important to note that vaporizers are not considered medical devices and their effectiveness for these purposes is not well-established.

It's worth noting that nebulizers and vaporizers are different from each other in terms of their purpose and usage. Nebulizers are used specifically for delivering medication, while vaporizers are used to produce steam or vapor, often for non-medical purposes.

Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.

Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.

These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.

Dyspnea is defined as difficulty or discomfort in breathing, often described as shortness of breath. It can range from mild to severe, and may occur during rest, exercise, or at any time. Dyspnea can be caused by various medical conditions, including heart and lung diseases, anemia, and neuromuscular disorders. It is important to seek medical attention if experiencing dyspnea, as it can be a sign of a serious underlying condition.

The Ventilation-Perfusion (V/Q) ratio is a measure used in respiratory physiology to describe the relationship between the amount of air that enters the alveoli (ventilation) and the amount of blood that reaches the alveoli to pick up oxygen (perfusion).

In a healthy lung, these two processes are well-matched, meaning that well-ventilated areas of the lung also have good blood flow. This results in a V/Q ratio close to 1.0.

However, certain lung conditions such as emphysema or pulmonary embolism can cause ventilation and perfusion to become mismatched, leading to a V/Q ratio that is either higher (ventilation exceeds perfusion) or lower (perfusion exceeds ventilation) than normal. This mismatch can result in impaired gas exchange and lead to hypoxemia (low oxygen levels in the blood).

The V/Q ratio is often used in clinical settings to assess lung function and diagnose respiratory disorders.

A negative pressure ventilator, also known as an iron lung, is a type of mechanical ventilator that creates a negative pressure environment around the patient's chest and abdomen to assist with breathing. This technology was widely used during the polio epidemic in the mid-20th century to help patients with respiratory paralysis caused by the disease.

In a negative pressure ventilator, the patient is placed inside an airtight chamber that is connected to a pump. The pump changes the air pressure within the chamber, creating a vacuum effect that causes the chest and abdomen to expand and contract, which in turn facilitates breathing. As the pressure around the chest decreases, the chest wall expands, allowing the lungs to fill with air. When the pressure increases, the chest wall contracts, pushing air out of the lungs.

Negative pressure ventilators have largely been replaced by positive pressure ventilators, which are more commonly used today. Positive pressure ventilators work by actively pushing air into the lungs, rather than relying on negative pressure to create a vacuum effect. However, negative pressure ventilators may still be used in certain situations where positive pressure ventilation is not appropriate or feasible.

Physical exertion is defined as the act of applying energy to physically demandable activities or tasks, which results in various body systems working together to produce movement and maintain homeostasis. It often leads to an increase in heart rate, respiratory rate, and body temperature, among other physiological responses. The level of physical exertion can vary based on the intensity, duration, and frequency of the activity.

It's important to note that engaging in regular physical exertion has numerous health benefits, such as improving cardiovascular fitness, strengthening muscles and bones, reducing stress, and preventing chronic diseases like obesity, diabetes, and heart disease. However, it is also crucial to balance physical exertion with adequate rest and recovery time to avoid overtraining or injury.

The supine position is a term used in medicine to describe a body posture where an individual is lying down on their back, with their face and torso facing upwards. This position is often adopted during various medical procedures, examinations, or when resting, as it allows for easy access to the front of the body. It is also the position automatically assumed by most people who are falling asleep.

It's important to note that in the supine position, the head can be flat on the surface or raised with the use of pillows or specialized medical equipment like a hospital bed. This can help to alleviate potential issues such as breathing difficulties or swelling in the face and head.

A reflex is an automatic, involuntary and rapid response to a stimulus that occurs without conscious intention. In the context of physiology and neurology, it's a basic mechanism that involves the transmission of nerve impulses between neurons, resulting in a muscle contraction or glandular secretion.

Reflexes are important for maintaining homeostasis, protecting the body from harm, and coordinating movements. They can be tested clinically to assess the integrity of the nervous system, such as the knee-j jerk reflex, which tests the function of the L3-L4 spinal nerve roots and the sensitivity of the stretch reflex arc.

Respiratory acidosis is a medical condition that occurs when the lungs are not able to remove enough carbon dioxide (CO2) from the body, leading to an increase in the amount of CO2 in the bloodstream and a decrease in the pH of the blood. This can happen due to various reasons such as chronic lung diseases like emphysema or COPD, severe asthma attacks, neuromuscular disorders that affect breathing, or when someone is not breathing deeply or frequently enough, such as during sleep apnea or drug overdose.

Respiratory acidosis can cause symptoms such as headache, confusion, shortness of breath, and in severe cases, coma and even death. Treatment for respiratory acidosis depends on the underlying cause but may include oxygen therapy, bronchodilators, or mechanical ventilation to help support breathing.

"Inhalation administration" is a medical term that refers to the method of delivering medications or therapeutic agents directly into the lungs by inhaling them through the airways. This route of administration is commonly used for treating respiratory conditions such as asthma, COPD (chronic obstructive pulmonary disease), and cystic fibrosis.

Inhalation administration can be achieved using various devices, including metered-dose inhalers (MDIs), dry powder inhalers (DPIs), nebulizers, and soft-mist inhalers. Each device has its unique mechanism of delivering the medication into the lungs, but they all aim to provide a high concentration of the drug directly to the site of action while minimizing systemic exposure and side effects.

The advantages of inhalation administration include rapid onset of action, increased local drug concentration, reduced systemic side effects, and improved patient compliance due to the ease of use and non-invasive nature of the delivery method. However, proper technique and device usage are crucial for effective therapy, as incorrect usage may result in suboptimal drug deposition and therapeutic outcomes.

Insufflation is a medical term that refers to the act of introducing a gas or vapor into a body cavity or passage, typically through a tube or surgical instrument. This procedure is often used in medical and surgical settings for various purposes, such as:

* To administer anesthesia during surgery (e.g., introducing nitrous oxide or other gases into the lungs)
* To introduce medication or other substances into the body (e.g., insufflating steroids into a joint)
* To perform diagnostic procedures (e.g., insufflating air or a contrast agent into the gastrointestinal tract to visualize it with X-rays)
* To clean out a body cavity (e.g., irrigating and insufflating the bladder during urological procedures).

It's important to note that insufflation should be performed under controlled conditions, as there are potential risks associated with introducing gases or vapors into the body, such as barotrauma (damage caused by changes in pressure) and infection.

The carotid body is a small chemoreceptor organ located near the bifurcation of the common carotid artery into the internal and external carotid arteries. It plays a crucial role in the regulation of respiration, blood pressure, and pH balance by detecting changes in the chemical composition of the blood, particularly oxygen levels, carbon dioxide levels, and hydrogen ion concentration (pH).

The carotid body contains specialized nerve endings called glomus cells that are sensitive to changes in these chemical parameters. When there is a decrease in oxygen or an increase in carbon dioxide or hydrogen ions, the glomus cells release neurotransmitters such as acetylcholine and dopamine, which activate afferent nerve fibers leading to the brainstem's nucleus tractus solitarius. This information is then integrated with other physiological signals in the brainstem, resulting in appropriate adjustments in breathing rate, depth, and pattern, as well as changes in heart rate and blood vessel diameter to maintain homeostasis.

Dysfunction of the carotid body can lead to various disorders, such as hypertension, sleep apnea, and chronic lung disease. In some cases, overactivity of the carotid body may result in conditions like primary breathing pattern disorders or pseudohypoxia, where the body responds as if it is experiencing hypoxia despite normal oxygen levels.

Hyperoxia is a medical term that refers to an abnormally high concentration of oxygen in the body or in a specific organ or tissue. It is often defined as the partial pressure of oxygen (PaO2) in arterial blood being greater than 100 mmHg.

This condition can occur due to various reasons such as exposure to high concentrations of oxygen during medical treatments, like mechanical ventilation, or due to certain diseases and conditions that cause the body to produce too much oxygen.

While oxygen is essential for human life, excessive levels can be harmful and lead to oxidative stress, which can damage cells and tissues. Hyperoxia has been linked to various complications, including lung injury, retinopathy of prematurity, and impaired wound healing.

The Respiratory Center is a group of neurons located in the medulla oblongata and pons within the brainstem that are responsible for controlling and regulating breathing. It receives inputs from various sources, including chemoreceptors that detect changes in oxygen and carbon dioxide levels in the blood, as well as mechanoreceptors that provide information about the status of the lungs and airways. Based on these inputs, the respiratory center generates signals that are sent to the diaphragm and intercostal muscles to control the rate and depth of breathing, ensuring adequate gas exchange in the lungs.

Damage to the respiratory center can result in abnormal breathing patterns or even respiratory failure, highlighting its critical role in maintaining proper respiratory function.

Noninvasive ventilation (NIV) refers to the delivery of mechanical ventilation without using an invasive airway, such as an endotracheal tube or tracheostomy. It is a technique used to support patients with respiratory insufficiency or failure, while avoiding the potential complications associated with intubation and invasive ventilation.

NIV can be provided through various interfaces, including nasal masks, full-face masks, or mouthpieces. The most common modes of NIV are continuous positive airway pressure (CPAP) and bilevel positive airway pressure (BiPAP), which provide a constant flow of pressurized air to maintain airway patency and support breathing efforts.

NIV is commonly used in the management of chronic respiratory conditions such as obstructive sleep apnea, COPD, and neuromuscular disorders, as well as acute respiratory failure due to causes such as pneumonia or exacerbation of chronic lung disease. However, it is not appropriate for all patients and should be used under the close supervision of a healthcare provider.

Bronchodilators are medications that relax and widen the airways (bronchioles) in the lungs, making it easier to breathe. They work by relaxing the smooth muscle around the airways, which allows them to dilate or open up. This results in improved airflow and reduced symptoms of bronchoconstriction, such as wheezing, coughing, and shortness of breath.

Bronchodilators can be classified into two main types: short-acting and long-acting. Short-acting bronchodilators are used for quick relief of symptoms and last for 4 to 6 hours, while long-acting bronchodilators are used for maintenance therapy and provide symptom relief for 12 hours or more.

Examples of bronchodilator agents include:

* Short-acting beta-agonists (SABAs) such as albuterol, levalbuterol, and pirbuterol
* Long-acting beta-agonists (LABAs) such as salmeterol, formoterol, and indacaterol
* Anticholinergics such as ipratropium, tiotropium, and aclidinium
* Combination bronchodilators that contain both a LABA and an anticholinergic, such as umeclidinium/vilanterol and glycopyrrolate/formoterol.

High-frequency jet ventilation (HFJV) is a type of mechanical ventilation that delivers breaths at a frequency greater than 100 times per minute, typically in the range of 240-360 breaths per minute. It uses a high-pressure jet of gas to deliver small tidal volumes (usually less than 2 ml/kg of ideal body weight) into the airway.

The jet ventilation is often combined with a low-level positive end-expiratory pressure (PEEP) to maintain some lung volume and prevent atelectasis during exhalation. HFJV can be used in both invasive and noninvasive modes, depending on the patient's condition and requirements.

This mode of ventilation is particularly useful in patients with severe respiratory distress syndrome (ARDS), bronchopleural fistula, or air leaks from lung injury, as it minimizes gas flow and reduces the risk of air leakage while still maintaining adequate oxygenation and carbon dioxide elimination. However, HFJV requires careful monitoring and expertise to ensure proper settings and avoid complications such as barotrauma, hemodynamic instability, or inadequate ventilation.

Fluid therapy, in a medical context, refers to the administration of fluids into a patient's circulatory system for various therapeutic purposes. This can be done intravenously (through a vein), intraosseously (through a bone), or subcutaneously (under the skin). The goal of fluid therapy is to correct or prevent imbalances in the body's fluids and electrolytes, maintain or restore blood volume, and support organ function.

The types of fluids used in fluid therapy can include crystalloids (which contain electrolytes and water) and colloids (which contain larger molecules like proteins). The choice of fluid depends on the patient's specific needs and condition. Fluid therapy is commonly used in the treatment of dehydration, shock, sepsis, trauma, surgery, and other medical conditions that can affect the body's fluid balance.

Proper administration of fluid therapy requires careful monitoring of the patient's vital signs, urine output, electrolyte levels, and overall clinical status to ensure that the therapy is effective and safe.

Reference values, also known as reference ranges or reference intervals, are the set of values that are considered normal or typical for a particular population or group of people. These values are often used in laboratory tests to help interpret test results and determine whether a patient's value falls within the expected range.

The process of establishing reference values typically involves measuring a particular biomarker or parameter in a large, healthy population and then calculating the mean and standard deviation of the measurements. Based on these statistics, a range is established that includes a certain percentage of the population (often 95%) and excludes extreme outliers.

It's important to note that reference values can vary depending on factors such as age, sex, race, and other demographic characteristics. Therefore, it's essential to use reference values that are specific to the relevant population when interpreting laboratory test results. Additionally, reference values may change over time due to advances in measurement technology or changes in the population being studied.

Humidity, in a medical context, is not typically defined on its own but is related to environmental conditions that can affect health. Humidity refers to the amount of water vapor present in the air. It is often discussed in terms of absolute humidity (the mass of water per unit volume of air) or relative humidity (the ratio of the current absolute humidity to the maximum possible absolute humidity, expressed as a percentage). High humidity can contribute to feelings of discomfort, difficulty sleeping, and exacerbation of respiratory conditions such as asthma.

Respiratory disorders are a group of conditions that affect the respiratory system, including the nose, throat (pharynx), windpipe (trachea), bronchi, lungs, and diaphragm. These disorders can make it difficult for a person to breathe normally and may cause symptoms such as coughing, wheezing, shortness of breath, and chest pain.

There are many different types of respiratory disorders, including:

1. Asthma: A chronic inflammatory disease that causes the airways to become narrow and swollen, leading to difficulty breathing.
2. Chronic obstructive pulmonary disease (COPD): A group of lung diseases, including emphysema and chronic bronchitis, that make it hard to breathe.
3. Pneumonia: An infection of the lungs that can cause coughing, chest pain, and difficulty breathing.
4. Lung cancer: A type of cancer that forms in the tissues of the lungs and can cause symptoms such as coughing, chest pain, and shortness of breath.
5. Tuberculosis (TB): A bacterial infection that mainly affects the lungs but can also affect other parts of the body.
6. Sleep apnea: A disorder that causes a person to stop breathing for short periods during sleep.
7. Interstitial lung disease: A group of disorders that cause scarring of the lung tissue, leading to difficulty breathing.
8. Pulmonary fibrosis: A type of interstitial lung disease that causes scarring of the lung tissue and makes it hard to breathe.
9. Pleural effusion: An abnormal accumulation of fluid in the space between the lungs and chest wall.
10. Lung transplantation: A surgical procedure to replace a diseased or failing lung with a healthy one from a donor.

Respiratory disorders can be caused by a variety of factors, including genetics, exposure to environmental pollutants, smoking, and infections. Treatment for respiratory disorders may include medications, oxygen therapy, breathing exercises, and lifestyle changes. In some cases, surgery may be necessary to treat the disorder.

The intercostal muscles are a group of muscles located between the ribs (intercostal spaces) in the thoracic region of the body. They play a crucial role in the process of breathing by assisting in the expansion and contraction of the chest wall during inspiration and expiration.

There are two sets of intercostal muscles: the external intercostals and the internal intercostals. The external intercostals run from the lower edge of one rib to the upper edge of the next lower rib, forming a layer that extends from the tubercles of the ribs down to the costochondral junctions (where the rib meets the cartilage). These muscles help elevate the ribcage during inspiration.

The internal intercostals are deeper and run in the opposite direction, originating at the lower edge of a rib and inserting into the upper edge of the next higher rib. They assist in lowering the ribcage during expiration.

Additionally, there is a third layer called the innermost intercostal muscles, which are even deeper than the internal intercostals and have similar functions. The intercostal membranes connect the ends of the ribs and complete the muscle layers between the ribs. Together, these muscles help maintain the structural integrity of the chest wall and contribute to respiratory function.

An exercise test, also known as a stress test or an exercise stress test, is a medical procedure used to evaluate the heart's function and response to physical exertion. It typically involves walking on a treadmill or pedaling a stationary bike while being monitored for changes in heart rate, blood pressure, electrocardiogram (ECG), and sometimes other variables such as oxygen consumption or gas exchange.

During the test, the patient's symptoms, such as chest pain or shortness of breath, are also closely monitored. The exercise test can help diagnose coronary artery disease, assess the severity of heart-related symptoms, and evaluate the effectiveness of treatments for heart conditions. It may also be used to determine a person's safe level of physical activity and fitness.

There are different types of exercise tests, including treadmill stress testing, stationary bike stress testing, nuclear stress testing, and stress echocardiography. The specific type of test used depends on the patient's medical history, symptoms, and overall health status.

Intensive care is a specialized level of medical care that is provided to critically ill patients. It's usually given in a dedicated unit of a hospital called the Intensive Care Unit (ICU) or Critical Care Unit (CCU). The goal of intensive care is to closely monitor and manage life-threatening conditions, stabilize vital functions, and support organs until they recover or the patient can be moved to a less acute level of care.

Intensive care involves advanced medical equipment and technologies, such as ventilators to assist with breathing, dialysis machines for kidney support, intravenous lines for medication administration, and continuous monitoring devices for heart rate, blood pressure, oxygen levels, and other vital signs.

The ICU team typically includes intensive care specialists (intensivists), critical care nurses, respiratory therapists, and other healthcare professionals who work together to provide comprehensive, round-the-clock care for critically ill patients.

Animal disease models are specialized animals, typically rodents such as mice or rats, that have been genetically engineered or exposed to certain conditions to develop symptoms and physiological changes similar to those seen in human diseases. These models are used in medical research to study the pathophysiology of diseases, identify potential therapeutic targets, test drug efficacy and safety, and understand disease mechanisms.

The genetic modifications can include knockout or knock-in mutations, transgenic expression of specific genes, or RNA interference techniques. The animals may also be exposed to environmental factors such as chemicals, radiation, or infectious agents to induce the disease state.

Examples of animal disease models include:

1. Mouse models of cancer: Genetically engineered mice that develop various types of tumors, allowing researchers to study cancer initiation, progression, and metastasis.
2. Alzheimer's disease models: Transgenic mice expressing mutant human genes associated with Alzheimer's disease, which exhibit amyloid plaque formation and cognitive decline.
3. Diabetes models: Obese and diabetic mouse strains like the NOD (non-obese diabetic) or db/db mice, used to study the development of type 1 and type 2 diabetes, respectively.
4. Cardiovascular disease models: Atherosclerosis-prone mice, such as ApoE-deficient or LDLR-deficient mice, that develop plaque buildup in their arteries when fed a high-fat diet.
5. Inflammatory bowel disease models: Mice with genetic mutations affecting intestinal barrier function and immune response, such as IL-10 knockout or SAMP1/YitFc mice, which develop colitis.

Animal disease models are essential tools in preclinical research, but it is important to recognize their limitations. Differences between species can affect the translatability of results from animal studies to human patients. Therefore, researchers must carefully consider the choice of model and interpret findings cautiously when applying them to human diseases.

Hypoventilation is a medical condition that refers to the decreased rate and depth of breathing, which leads to an inadequate exchange of oxygen and carbon dioxide in the lungs. As a result, there is an increase in the levels of carbon dioxide (hypercapnia) and a decrease in the levels of oxygen (hypoxemia) in the blood. Hypoventilation can occur due to various reasons such as respiratory muscle weakness, sedative or narcotic overdose, chest wall deformities, neuromuscular disorders, obesity hypoventilation syndrome, and sleep-disordered breathing. Prolonged hypoventilation can lead to serious complications such as respiratory failure, cardiac arrhythmias, and even death.

Posture is the position or alignment of body parts supported by the muscles, especially the spine and head in relation to the vertebral column. It can be described as static (related to a stationary position) or dynamic (related to movement). Good posture involves training your body to stand, walk, sit, and lie in positions where the least strain is placed on supporting muscles and ligaments during movement or weight-bearing activities. Poor posture can lead to various health issues such as back pain, neck pain, headaches, and respiratory problems.

A newborn infant is a baby who is within the first 28 days of life. This period is also referred to as the neonatal period. Newborns require specialized care and attention due to their immature bodily systems and increased vulnerability to various health issues. They are closely monitored for signs of well-being, growth, and development during this critical time.

Impedance cardiography is a non-invasive method to measure cardiac output and systemic vascular resistance. It uses low-frequency electrical currents passed through the thorax to measure changes in impedance or resistance to flow during each heartbeat. This allows for the calculation of stroke volume and cardiac output. Impedance cardiography can provide continuous, real-time monitoring of cardiovascular function, making it useful in critical care settings and for tracking changes in patients with heart failure or other cardiovascular conditions.

X-ray computed tomography (CT or CAT scan) is a medical imaging method that uses computer-processed combinations of many X-ray images taken from different angles to produce cross-sectional (tomographic) images (virtual "slices") of the body. These cross-sectional images can then be used to display detailed internal views of organs, bones, and soft tissues in the body.

The term "computed tomography" is used instead of "CT scan" or "CAT scan" because the machines take a series of X-ray measurements from different angles around the body and then use a computer to process these data to create detailed images of internal structures within the body.

CT scanning is a noninvasive, painless medical test that helps physicians diagnose and treat medical conditions. CT imaging provides detailed information about many types of tissue including lung, bone, soft tissue and blood vessels. CT examinations can be performed on every part of the body for a variety of reasons including diagnosis, surgical planning, and monitoring of therapeutic responses.

In computed tomography (CT), an X-ray source and detector rotate around the patient, measuring the X-ray attenuation at many different angles. A computer uses this data to construct a cross-sectional image by the process of reconstruction. This technique is called "tomography". The term "computed" refers to the use of a computer to reconstruct the images.

CT has become an important tool in medical imaging and diagnosis, allowing radiologists and other physicians to view detailed internal images of the body. It can help identify many different medical conditions including cancer, heart disease, lung nodules, liver tumors, and internal injuries from trauma. CT is also commonly used for guiding biopsies and other minimally invasive procedures.

In summary, X-ray computed tomography (CT or CAT scan) is a medical imaging technique that uses computer-processed combinations of many X-ray images taken from different angles to produce cross-sectional images of the body. It provides detailed internal views of organs, bones, and soft tissues in the body, allowing physicians to diagnose and treat medical conditions.

Hypocapnia is a medical term that refers to a condition where there is an abnormally low level of carbon dioxide (CO2) in the blood. Carbon dioxide is a gas that is produced by the body's cells as they carry out their normal metabolic processes, and it is transported in the bloodstream to the lungs, where it is exhaled out of the body during breathing.

Hypocapnia can occur when a person breathes too quickly or too deeply, which can cause too much CO2 to be exhaled from the body. This condition can also result from certain medical conditions that affect breathing, such as chronic obstructive pulmonary disease (COPD), asthma, and sleep apnea.

Mild hypocapnia may not cause any noticeable symptoms, but more severe cases can lead to symptoms such as dizziness, lightheadedness, headache, confusion, and rapid breathing. In extreme cases, it can lead to life-threatening conditions such as respiratory failure or cardiac arrest.

Hypocapnia is typically diagnosed through blood tests that measure the level of CO2 in the blood. Treatment for hypocapnia may involve addressing any underlying medical conditions that are causing it, as well as providing supportive care to help the person breathe more effectively.

The Respiratory System is a complex network of organs and tissues that work together to facilitate the process of breathing, which involves the intake of oxygen and the elimination of carbon dioxide. This system primarily includes the nose, throat (pharynx), voice box (larynx), windpipe (trachea), bronchi, bronchioles, lungs, and diaphragm.

The nostrils or mouth take in air that travels through the pharynx, larynx, and trachea into the lungs. Within the lungs, the trachea divides into two bronchi, one for each lung, which further divide into smaller tubes called bronchioles. At the end of these bronchioles are tiny air sacs known as alveoli where the exchange of gases occurs. Oxygen from the inhaled air diffuses through the walls of the alveoli into the bloodstream, while carbon dioxide, a waste product, moves from the blood to the alveoli and is exhaled out of the body.

The diaphragm, a large muscle that separates the chest from the abdomen, plays a crucial role in breathing by contracting and relaxing to change the volume of the chest cavity, thereby allowing air to flow in and out of the lungs. Overall, the Respiratory System is essential for maintaining life by providing the body's cells with the oxygen needed for metabolism and removing waste products like carbon dioxide.

Treatment outcome is a term used to describe the result or effect of medical treatment on a patient's health status. It can be measured in various ways, such as through symptoms improvement, disease remission, reduced disability, improved quality of life, or survival rates. The treatment outcome helps healthcare providers evaluate the effectiveness of a particular treatment plan and make informed decisions about future care. It is also used in clinical research to compare the efficacy of different treatments and improve patient care.

Residual Volume (RV) is the amount of air that remains in the lungs after a forced exhale, also known as the "expiratory reserve volume." It is the lowest lung volume that can be reached during a forced exhalation and cannot be completely emptied due to the presence of alveoli that are too small or too far from the airways. This volume is important for maintaining the structural integrity of the lungs and preventing their collapse. Any additional air that enters the lungs after this point will increase the total lung capacity. The normal residual volume for an average adult human is typically around 1 to 1.5 liters.

Nonparametric statistics is a branch of statistics that does not rely on assumptions about the distribution of variables in the population from which the sample is drawn. In contrast to parametric methods, nonparametric techniques make fewer assumptions about the data and are therefore more flexible in their application. Nonparametric tests are often used when the data do not meet the assumptions required for parametric tests, such as normality or equal variances.

Nonparametric statistical methods include tests such as the Wilcoxon rank-sum test (also known as the Mann-Whitney U test) for comparing two independent groups, the Wilcoxon signed-rank test for comparing two related groups, and the Kruskal-Wallis test for comparing more than two independent groups. These tests use the ranks of the data rather than the actual values to make comparisons, which allows them to be used with ordinal or continuous data that do not meet the assumptions of parametric tests.

Overall, nonparametric statistics provide a useful set of tools for analyzing data in situations where the assumptions of parametric methods are not met, and can help researchers draw valid conclusions from their data even when the data are not normally distributed or have other characteristics that violate the assumptions of parametric tests.

Pneumonia is an infection or inflammation of the alveoli (tiny air sacs) in one or both lungs. It's often caused by bacteria, viruses, or fungi. Accumulated pus and fluid in these air sacs make it difficult to breathe, which can lead to coughing, chest pain, fever, and difficulty breathing. The severity of symptoms can vary from mild to life-threatening, depending on the underlying cause, the patient's overall health, and age. Pneumonia is typically diagnosed through a combination of physical examination, medical history, and diagnostic tests such as chest X-rays or blood tests. Treatment usually involves antibiotics for bacterial pneumonia, antivirals for viral pneumonia, and supportive care like oxygen therapy, hydration, and rest.

I believe there may be some confusion in your question. "Rabbits" is a common name used to refer to the Lagomorpha species, particularly members of the family Leporidae. They are small mammals known for their long ears, strong legs, and quick reproduction.

However, if you're referring to "rabbits" in a medical context, there is a term called "rabbit syndrome," which is a rare movement disorder characterized by repetitive, involuntary movements of the fingers, resembling those of a rabbit chewing. It is also known as "finger-chewing chorea." This condition is usually associated with certain medications, particularly antipsychotics, and typically resolves when the medication is stopped or adjusted.

Artificial organs are medical devices that are implanted in the human body to replace the function of a damaged, diseased, or failing organ. These devices can be made from a variety of materials, including metals, plastics, and synthetic biomaterials. They are designed to mimic the structure and function of natural organs as closely as possible, with the goal of improving the patient's quality of life and extending their lifespan.

Some examples of artificial organs include:

1. Artificial heart: A device that is implanted in the chest to replace the function of a failing heart. It can be used as a temporary or permanent solution for patients with end-stage heart failure.
2. Artificial pancreas: A device that is used to treat type 1 diabetes by regulating blood sugar levels. It consists of an insulin pump and a continuous glucose monitor, which work together to deliver insulin automatically based on the patient's needs.
3. Artificial kidney: A device that filters waste products from the blood, similar to a natural kidney. It can be used as a temporary or permanent solution for patients with end-stage renal disease.
4. Artificial lung: A device that helps patients with respiratory failure breathe by exchanging oxygen and carbon dioxide in the blood.
5. Artificial bladder: A device that is implanted in the body to help patients with bladder dysfunction urinate.
6. Artificial eyes: Prosthetic devices that are used to replace a missing or damaged eye, providing cosmetic and sometimes functional benefits.

It's important to note that while artificial organs can significantly improve the quality of life for many patients, they are not without risks. Complications such as infection, rejection, and device failure can occur, and ongoing medical care is necessary to monitor and manage these risks.

Critical care, also known as intensive care, is a medical specialty that deals with the diagnosis and management of life-threatening conditions that require close monitoring and organ support. Critical care medicine is practiced in critical care units (ICUs) or intensive care units of hospitals. The goal of critical care is to prevent further deterioration of the patient's condition, to support failing organs, and to treat any underlying conditions that may have caused the patient to become critically ill.

Critical care involves a multidisciplinary team approach, including intensivists (specialist doctors trained in critical care), nurses, respiratory therapists, pharmacists, and other healthcare professionals. The care provided in the ICU is highly specialized and often involves advanced medical technology such as mechanical ventilation, dialysis, and continuous renal replacement therapy.

Patients who require critical care may have a wide range of conditions, including severe infections, respiratory failure, cardiovascular instability, neurological emergencies, and multi-organ dysfunction syndrome (MODS). Critical care is an essential component of modern healthcare and has significantly improved the outcomes of critically ill patients.

Air filters are devices used to remove contaminants and impurities from the air. They work by trapping particles that flow through them, such as dust, pollen, mold spores, and bacteria. Air filters are often used in heating, ventilation, and air conditioning (HVAC) systems to improve indoor air quality. They can also be found in portable air cleaners and vacuum cleaners.

Air filters are typically made of a porous material such as fiberglass, cotton, or paper, which is designed to trap particles of different sizes. The efficiency of an air filter is measured by its Minimum Efficiency Reporting Value (MERV) rating, which ranges from 1 to 16, with higher ratings indicating better filtration performance.

Medical-grade air filters, such as High Efficiency Particulate Air (HEPA) filters, are designed to remove at least 99.97% of particles that are 0.3 microns or larger in diameter. These filters are commonly used in hospitals and medical facilities to help prevent the spread of infectious diseases.

Respiratory therapy is a healthcare profession that specializes in the diagnosis, treatment, and management of respiratory disorders and diseases. Respiratory therapists (RTs) work under the direction of physicians to provide care for patients with conditions such as chronic obstructive pulmonary disease (COPD), asthma, cystic fibrosis, sleep apnea, and neuromuscular diseases that affect breathing.

RTs use a variety of techniques and treatments to help patients breathe more easily, including oxygen therapy, aerosol medication delivery, chest physiotherapy, mechanical ventilation, and patient education. They also perform diagnostic tests such as pulmonary function studies to assess lung function and help diagnose respiratory conditions.

RTs work in a variety of healthcare settings, including hospitals, clinics, long-term care facilities, and home health agencies. They may provide care for patients of all ages, from premature infants to the elderly. The overall goal of respiratory therapy is to help patients achieve and maintain optimal lung function and quality of life.

A tracheostomy is a surgically created opening through the neck into the trachea (windpipe). It is performed to provide an airway in cases where the upper airway is obstructed or access to the lower airway is required, such as in prolonged intubation, severe trauma, or chronic lung diseases. The procedure involves making an incision in the front of the neck and creating a direct opening into the trachea, through which a tracheostomy tube is inserted to maintain the patency of the airway. This allows for direct ventilation of the lungs, suctioning of secretions, and prevention of complications associated with upper airway obstruction.

Maximal Expiratory Flow Rate (MEFR) is a measure of how quickly a person can exhale air from their lungs. It is often used in pulmonary function testing to assess the degree of airflow obstruction in conditions such as chronic obstructive pulmonary disease (COPD) or asthma.

The MEFR is typically measured by having the person take a deep breath and then exhale as forcefully and quickly as possible into a device that measures the volume and flow of air. The MEFR is calculated as the maximum flow rate achieved during the exhalation maneuver, usually expressed in liters per second (L/s) or seconds (L/sec).

MEFR can be measured at different lung volumes, such as at functional residual capacity (FRC) or at total lung capacity (TLC), to provide additional information about the severity and location of airflow obstruction. However, MEFR is not as commonly used in clinical practice as other measures of pulmonary function, such as forced expiratory volume in one second (FEV1) or forced vital capacity (FVC).

I apologize, but "sheep" is not a term that has a medical definition. It is a common animal with the scientific name Ovis aries. If you have any medical or health-related questions, I would be happy to try and help answer those for you.

Electric impedance is a measure of opposition to the flow of alternating current (AC) in an electrical circuit or component, caused by both resistance (ohmic) and reactance (capacitive and inductive). It is expressed as a complex number, with the real part representing resistance and the imaginary part representing reactance. The unit of electric impedance is the ohm (Ω).

In the context of medical devices, electric impedance may be used to measure various physiological parameters, such as tissue conductivity or fluid composition. For example, bioelectrical impedance analysis (BIA) uses electrical impedance to estimate body composition, including fat mass and lean muscle mass. Similarly, electrical impedance tomography (EIT) is a medical imaging technique that uses electric impedance to create images of internal organs and tissues.

In a healthy, young human adult, tidal volume is approximately 500 ml per inspiration or 7 ml/kg of body mass. Tidal volume ... Tidal volume (symbol VT or TV) is the volume of air moved into or out of the lungs during a normal breath. ... Tidal volume is measured in milliliters and ventilation volumes are estimated based on a patient's ideal body mass. Measurement ... Ricard JD (May 2003). "Are we really reducing tidal volume-and should we?". American Journal of Respiratory and Critical Care ...
With increasing erosion, there is increasing tidal volume creating a self-perpetuating system.[better source needed] Tidal ... Tidal scour is "sea-floor erosion caused by strong tidal currents resulting in the removal of inshore sediments and formation ... Tidal force can also contribute to bridge scour.[better source needed] Research on tidal scour is largely centered at Elkhorn ... the amount of tidal scour can be quantified.[better source needed] Sediment grab samples show that in areas demonstrating tidal ...
A music video was expected to be released.[volume & issue needed] Credits adapted from Tidal. Amanda Ava Koci - vocals, ... "Credits / Diamonds & Dancefloors / Ava Max". Tidal. Retrieved 2023-07-19. "Ava Max: Ghost" (in Finnish). Musiikkituottajat. ...
IMPLEMENTATION When treating atelectasis - Therapy should be volume-oriented 2. Tidal volumes(VT) must be measured 3. VT goals ... When treating atelectasis, IPPB is only useful in the treatment of atelectasis if the volume delivered exceeds those volumes ...
Tidal volumes ≤ 1 ml/Kg are used during HFJV. This combination of small tidal volumes delivered for very short periods of time ... HFOV generates very low tidal volumes that are generally less than the dead space of the lung. Tidal volume is dependent on ... inspiratory time will all increase tidal volume and eliminate CO2. Increasing the tidal volume will also tend to increase the ... Increasing the % Inspiratory Time will also increase the volume of gas moved or tidal volume. Decreasing the frequency, ...
Tidal Dynamics Volume I: Theory and Analysis of Tidal Forces; Volume II Extreme Tidal Peaks and Coastal Flooding. 3rd ed. West ... "Tide Predictions & Data Tidal Current Predictions and Data Data Access Problems FAQ - Tide Predictions and Data". National ... have been called perigean spring tides and generally increase the normal tidal range by a couple of inches. The Ash Wednesday ...
"Credits / Family Dinner - Volume 2 by Snarky Puppy". Tidal. Retrieved 16 March 2021. "Short Stories". AllMusic. 10 June 2016. ... "Jacob Collier Announces The Next Volume Of Wildly Ambitious New Project: Djesse - Volume 2 Out June 28 On Geffen/Decca". Shore ... "Credits / CASE STUDY 01 by Daniel Caesar". Tidal. Retrieved 16 March 2021. "Credits / Everyday Life by Coldplay". Tidal. ... "Credits / WONDERBLOOM by Becca Stevens". Tidal. Retrieved 17 March 2021. "Credits / December Baby by JoJo". Tidal. Retrieved 16 ...
Influence of tidal volume on the distribution of gas between the lungs and the stomach in the nonintubated patient receiving ... Effects of smaller tidal volumes during basic life support: good ventilation, less risk? Resuscitation 1999: 43:25-29. Dörges V ... Manual resuscitators have no built-in tidal volume control - the amount of air used to force-inflate the lungs during each ... It was also found that when guideline-excessive tidal volumes were delivered, changes in blood flow were observed that were ...
Open lung ventilation is a ventilatory strategy that combines small tidal volumes (to lessen alveolar overdistension) and an ... This may be reduced by using smaller tidal volumes. During positive pressure ventilation, atelectatic regions will inflate, ... A 2018 systematic review by The Cochrane Collaboration provided evidence that low tidal volume ventilation reduced post ... Alveolar overdistension is mitigated by using small tidal volumes, maintaining a low plateau pressure, and most effectively by ...
Brochard LJ (November 2009). "Tidal volume during acute lung injury: let the patient choose?". Intensive Care Medicine. 35 (11 ...
Endurance training typically results in an increase in tidal volume. Muscles involved in respiration, including the diaphragm ...
Low tidal volumes (Vt) may cause a permitted rise in blood carbon dioxide levels and collapse of alveoli because of their ... Previously, mechanical ventilation aimed to achieve tidal volumes (Vt) of 12-15 ml/kg (where the weight is ideal body weight ... A shunt is a perfusion without ventilation within a lung region.[citation needed] Low tidal volume ventilation was the primary ... Malhotra A (2007). "Low-tidal-volume ventilation in the acute respiratory distress syndrome". N Engl J Med. 357 (11): 1113-20. ...
"Stellar Tidal Streams in Spiral Galaxies of the Local Volume". Retrieved 2012-07-21. Paudel, Sanjaya; Duc, Pierre-Alain; Côté, ... The influence of tidal interactions, ram pressure stripping, and accreting gas envelopes". Astronomy & Astrophysics. 553: 1741- ...
"Stellar Tidal Streams in Spiral Galaxies of the Local Volume". Retrieved 2012-07-21. Chung, A.; Van Gorkom, J.H.; Kenney, J.F.P ... being the remnants of a much smaller galaxy that has been torn apart by NGC 4651's tidal forces, something that explains why ...
... and remove from the lungs tidal volume aliquots of conditioned perfluorocarbon (PFC). One research group led by Thomas H. ... it is possible to maintain better control of respiratory variables such as liquid functional residual capacity and tidal volume ... Conventional mechanical ventilation delivers tidal volume breaths on top of it. This mode of liquid ventilation currently seems ... In order to correctly and effectively conduct PLV, it is essential to properly dose a patient to a specific lung volume (10-15 ...
Administered intravenously, doxapram stimulates an increase in tidal volume, and respiratory rate. Doxapram stimulates ...
It used to be the most common complication of mechanical ventilation but can usually be avoided by limiting tidal volume and ... Ventilator induced lung injury is often associated with high tidal volumes (Vt). Other injuries with similar causes are ... and contributory factors probably include tidal volume, positive end-expiratory pressure and respiratory rate. There is no ... Barotraumas of ascent, also called decompression barotrauma, are also caused when the free change of volume of the gas in a ...
The liquid ventilator is always volume-controlled because the specified tidal volume of PFC must be accurately delivered and ... R. Robert; P. Micheau; S. Cyr; O. Lesur; J.P. Praud; H. Wallti (2005). "A prototype of volume-controlled tidal liquid ... R. Robert; P. Micheau; H. Walti (2009). "Optimal expiratory volume profile in tidal liquid ventilation under steady state ... the pump generates a positive driving pressure in the trachea to ensure the PFC insertion of the tidal volume. During the ...
RCi is the percent contribution of the rib cage excursions to the tidal volume Vt. The %RCi contribution to Tidal Volume ratio ... Tidal volume (Vt) is the volume inspired and expired with each breath. Variability in the wave form can be used to ... With this model, tidal volume (Vt) was calculated as the sum of the anteroposterior dimensions of the rib cage and abdomen, and ... Minute ventilation is equivalent to tidal volume multiplied by respiratory rate and is used to assess metabolic activity. Peak ...
Drug particle deposition is associated with mean residence time and tidal volume. An increase in mean residence time or tidal ... Suitable for older patients and children Better patient satisfaction due to the visible aerosols Easily employed with tidal ... volume enhances drug deposition in lungs, while an increase in air flow decreases the mean residence time, resulting in the ...
Because the total tidal volume ( V T {\displaystyle V_{T}} ) is made up of V A + V d {\displaystyle V_{A}+V_{d}} (alveolar ... This is given as a ratio of dead space to tidal volume. It differs from anatomical dead space as measured by Fowler's method as ... The Bohr equation is used to quantify the ratio of physiological dead space to the total tidal volume, and gives an indication ... is the tidal volume; P a CO 2 {\displaystyle P_{a\,{\ce {CO2}}}} is the partial pressure of carbon dioxide in the arterial ...
A tidal prism is the volume of water in an estuary or inlet between mean high tide and mean low tide, or the volume of water ... The inter-tidal prism volume can be expressed by the relationship: P=H A, where H is the average tidal range and A is the ... The size of ebb tidal deltas is proportional to tidal prism. If tidal prism increases, there is an increase in deltas and ... Simple tidal prism models stated the relationship of river discharge and inflowing ocean water as Prism=Volume of ocean water ...
"Baby / Quality Control". Tidal. Retrieved August 1, 2019. "Come On / Quality Control". Tidal. Retrieved August 1, 2019. " ... "Longtime / Quality Control". Tidal. Retrieved August 1, 2019. "Intro / Quality Control". Tidal. Retrieved August 1, 2019. ... "Soakin Wet / Quality Control". Tidal. Retrieved August 1, 2019. "Leave Em Alone / Quality Control". Tidal. Retrieved August 1, ... Control the Streets, Volume 2 received mixed reviews from critics. At Metacritic, the album received an average score of 58 ...
This allows much better ventilation, with improved tidal volume, and increased blood oxygenation. Positive pressure ventilation ...
Dual-control modes are pressure-controlled modes with an exhaled tidal volume target. They work on a breath-by-breath basis and ... Assist/control A/C CMV Volume assist/control Volume control Volume limited ventilation Volume controlled ventilation Controlled ... The ventilator will attempt to deliver the set tidal volume by utilizing whatever pressure is required to reach its setting. A ... Names such as volume control ventilation and volume cycled ventilation in modern usage refer to the Assist Control mode. ...
For example, Amazon, Tidal, and YouTube do not increase the volume of tracks. Some services do not normalize audio, for example ... Amsen, Eva (30 July 2019). "Why We Don't Turn Down The Volume When The Music Gets Louder". Forbes. Retrieved 5 August 2019. ... "Why Spotify Lowered the Volume of Songs and Ended Hegemonic Loudness". VICE News. Retrieved 8 June 2020. Shepherd, Ian (17 ... "Audio gain in volume signals loss for listeners". The Baltimore Sun. Retrieved 2 September 2010. "About Us". Turn Me Up!. ...
Inhalational anesthetics elicit bronchodilation, an increase in respiratory rate, and reduced tidal volume. The net effect is ... Respiratory rate and inspiratory volume will also affect the promptness of anesthesia onset, as will the extent of pulmonary ... and patient respiratory rate and inspiratory volume. For gases that have minimal tissue solubility, termination of anesthesia ...
Powering nations tomorrow report 2019 makes note of record volumes being supplied through tidal stream technology. Invented by ... A tidal stream generator, often referred to as a tidal energy converter (TEC), is a machine that extracts energy from moving ... A database of tidal energy developers is kept up-to-date here: Tidal energy developers The world's first marine energy test ... A tidal kite turbine is an underwater kite system or paravane that converts tidal energy into electricity by moving through the ...
The counterlung is a part of the loop which is designed to change in volume by the same amount as the user's tidal volume when ... The amount processed during each breath depends on the tidal volume of that breath. Towards the end of inhalation the bellows ... The volume of the counterlung should allow for the maximum likely breath volume of a user, but does not generally need to match ... The depth compensating systems discharge a portion of the diver's tidal volume which varies in inverse proportion to the ...
The volume-cycled ventilation includes the volume-control function and delivers a set tidal volume. The pressure is not a fixed ... The tidal volume varies depending on the resistance and elastance of the respiratory system. Pressure-cycled ventilation can ... The longer, deeper inspiratory flows by the patient will result in a larger tidal volume. This method of mechanical ventilation ... Any given volume will correspond to a specific pressure on the pressure-volume curve and vice versa in any case. Settings on ...
In a healthy, young human adult, tidal volume is approximately 500 ml per inspiration or 7 ml/kg of body mass. Tidal volume ... Tidal volume (symbol VT or TV) is the volume of air moved into or out of the lungs during a normal breath. ... Tidal volume is measured in milliliters and ventilation volumes are estimated based on a patients ideal body mass. Measurement ... Ricard JD (May 2003). "Are we really reducing tidal volume-and should we?". American Journal of Respiratory and Critical Care ...
Volume 11, Number 10-October 2005 About the Cover. Of Tidal Waves and Human Frailty Downloads ... Of Tidal Waves and Human Frailty. Volume 11, Number 10-October 2005 ... Potter P. Of Tidal Waves and Human Frailty. Emerging Infectious Diseases. 2005;11(10):1653-1654. doi:10.3201/eid1110.ac1110.. ... Potter P. Of Tidal Waves and Human Frailty. Emerg Infect Dis. 2005;11(10):1653-1654. https://doi.org/10.3201/eid1110.ac1110. ...
... mechanical ventilation with a lower tidal volume than is traditionally used results in decreased mortality and increases the ... Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory ... with ventilation with a lower tidal volume, which involved an initial tidal volume of 6 ml per kilogram of predicted body ... mortality was lower in the group treated with lower tidal volumes than in the group treated with traditional tidal volumes ( ...
Assessment of tidal volume and gas leak during mask ventilation of preterm infants in the delivery room ... Aim The aim was to compare resuscitators estimates of tidal volume (VT) and face mask leak with measured values during ... Assessment of tidal volume and gas leak during mask ventilation of preterm infants in the delivery room ... expired tidal volume (VTe) delivered was 8.7 ml/kg (5.3-11.3). VTe varied widely during each resuscitation and between ...
The six home ventilators tested in the study were able to maintain a minimal tidal volume during an increase in airway ... minimal tidal volume during a non-intentional leak was more difficult and was associated with large variations in tidal volume ... Are home ventilators able to guarantee a minimal tidal volume? Intensive Care Med. 2010 Jun;36(6):1008-14. doi: 10.1007/s00134- ... Objective: The aim of the study was to evaluate the ability of home ventilators to maintain a minimal tidal volume during ...
Forest plot for tidal volume , 6 mL/kg ideal body weight across ventilator modes. VT = tidal volume, PSV = pressure support ... Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory ... VT = tidal volume, PSV = pressure support ventilation, VCV = volume control ventilation, MMV = mandatory minute ventilation, AF ... Variability of Tidal Volume in Patient-Triggered Mechanical Ventilation in ARDS. Sophie Perinel-Ragey, Loredana Baboi, Claude ...
... One prevalent approach is ventilation with large tidal volumes. Normal tidal volumes are much smaller in ... traditional tidal is. Their smaller lung sizes been to use similar tidal volumes ( 10-12 mL/kg ) tidal volume in copd... Normal ... Olv has become so infrequent that the question arises whether these tidal volume in copd tidal volumes 10-12. Reserve volume ( ... traditional tidal volume litres ( 500 ml ) US over a period. By the following terms: tidal volume to a non-injurious stress ...
Tidal Volume. Oleva Berard August 19, 2019. 0 Few local bands make waves quite like St. Louis "empower pop" band Tidal Volume. ... of Tidal Volume about the impressive career goals the band has accomplished so far and what we can expect from Tidal Volume ... When can we look forward to new music from Tidal Volume?. Really soon! Were releasing three songs this fall. Were wrapping up ... Tags jukebox the ghost Ludo modern anxiety plain white ts tidal volume ...
The tidal volume that is delivered from the machine is monitored. If the tidal volume equals the minimum set tidal volume, the ... However, if the tidal volume is less than the set tidal volume, the ventilator switches to a volume-controlled breath with ... The ventilator monitors each breath and compares the delivered tidal volume with the set tidal volume. If the delivered volume ... When a low tidal volume is used, sighs are preset at 1.5-2 times the tidal volume and delivered 6-8 times an hour if the peak ...
Dr Holley summarizes a survey reporting that while a majority of physicians support use of low tidal volume ventilation for ... Examples of inappropriate LTVV strategies are using plateau pressure but not tidal volume limits, and calculating tidal volume ... Neuromuscular blockade (NMB),[1] prone positioning,[2] and low tidal volume ventilation (LTVV)[3] have all shown a mortality ... A Critical Care Clinician Survey Comparing Attitudes and Perceived Barriers to Low Tidal Volume Ventilation With Actual ...
1500ml Tidal Volume from China, Chinas leading air breathing apparatus product, with strict quality control medical ventilator ... Alarms:Audible and/or visual alarms for ventilation volume,tidal volume,oxygen concentration,asphyxia,airway pressure, ... Frequency-Volume and any two waveforms simultaneously on screen. · Monitor Parameters: tidal volume, respiration rate, airway ... Sigh: Ability to insert 1-8 sigh breaths in every 100 breaths, ventilation should be no less than 1.5the tidal volume ...
What tidal volumes should be used in patients without acute lung injury?. In: Anesthesiology. 2007 ; Vol. 106, No. 6. pp. 1226- ... What tidal volumes should be used in patients without acute lung injury? Anesthesiology. 2007 Jun;106(6):1226-1231. doi: ... What tidal volumes should be used in patients without acute lung injury? / Schultz, Marcus J.; Haitsma, Jack J.; Slutsky, ... Schultz, M. J., Haitsma, J. J., Slutsky, A. S., & Gajic, O. (2007). What tidal volumes should be used in patients without acute ...
Adverse effects of large tidal volume and low PEEP in canine acid aspiration. / Corbridge, T. C.; Wood, L. D H; Crawford, G. P ... Adverse effects of large tidal volume and low PEEP in canine acid aspiration. In: American Review of Respiratory Disease. 1990 ... Corbridge, TC, Wood, LDH, Crawford, GP, Chudoba, MJ, Yanos, J & Sznajder, JI 1990, Adverse effects of large tidal volume and ... Adverse effects of large tidal volume and low PEEP in canine acid aspiration. American Review of Respiratory Disease. 1990;142( ...
Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory ... Evidence only proves low surpasses high tidal volume (VT) for acute respiratory distress syndrome (ARDS). Intermediate VT is a ... Low tidal volume ventilation use remains low in patients with acute respiratory distress syndrome at a single center. ... High-tidal-volume mechanical ventilation and lung inflammation in intensive care patients with normal lungs. american journal ...
of controlled and assisted breaths reduces tidal volume variations and ensures lower driving pressure. A low tidal volume ... Target protective tidal volumes. PRVC is a true volume-targeted mode that automatically adapts the inspiratory pressure to ... Tidal hyperinflation during low tidal volume ventilation in acute respiratory distress syndrome. Am J Respir Crit Care Med. ... A low tidal volume strategy can therefore be maintained when a patient start breathing spontaneously. Our interactive Automode ...
... with a tidal volume (Vt) of 7 ml kg− 1 ideal body weight (IBW), 10 cmH2O positive end-expiratory pressure (PEEP) combined with ... Low tidal volume positive end-expiratory pressure versus high tidal volume zero-positive end-expiratory pressure and ... the tidal volume was set at 10 ml kg− 1 IBW without PEEP and RM. In contrast, in LPV group, patients were provided with a tidal ... Low tidal volume with PEEP and recruitment expedite the recovery of pulmonary function. Int J Clin Exp Pathol. 2015;8(11):14305 ...
VT: Tidal volume. VE: Ventilation. * Indicates statistical significance compared to baseline. † Indicates significant treatment ... The mask was attached to a bidirectional digital turbine flow meter to measure the volume of inspired and expired air. A sample ...
Changes of vital signs and ventilator settings in case 1. TV, tidal volume; PIP, peak inspiratory pressure; EtCO2, end-tidal ... Changes of vital signs and ventilator settings in case 2. TV, tidal volume; PIP, peak inspiratory pressure; EtCO2, end-tidal ... at a tidal volume (TV) of 450 mL, respiratory rate of 12 breaths/min, positive end-expiratory pressure (PEEP) of 5 cmH2O, and ... She was ventilated by pressure-controlled ventilation, volume-guaranteed mode (PCV-VG®, GE Healthcare, Little Chalfont, England ...
The tidal effects in the Finite-volumE Sea ice-Ocean Model (FESOM2.1): a comparison between parameterised tidal mixing and ... 2021). The tidal effects in the Finite-volumE Sea ice--Ocean Model (FESOM2.1): a comparison between parameterized tidal mixing ... By comparing the effect of a tidal mixing parameterisation and tidal forcing on the ocean state, we assess the advantages and ... The authors seem to believe that having the long internal tidal waves in their model they have implemented "tidal mixing". This ...
Surgical Tidal Volumes and Postop Complications, New-Onset Postop Afib and Stroke, Review of Bariatric Surgery, and more. ... Surgical Tidal Volumes and Postop Complications, New-Onset Postop Afib and Stroke, Review of Bariatric Surgery, and more. ...
... tidal volume (p , 0.01), end-inspiratory volume (p , 0.04), end-expiratory volume (p , 0.03), and in the activity of the ... tidal volume (p , 0.01), end-inspiratory volume (p , 0.04), end-expiratory volume (p , 0.03), and in the activity of the ... load application yielded significant differences between using nasal and oral interfaces with an increase in the tidal volume ( ... load application yielded significant differences between using nasal and oral interfaces with an increase in the tidal volume ( ...
... tidal volume; inspiration time; expiration time; relaxation time; peak expiratory flow; and minute volume.. Determination of ... Exposure chamber volume: approx. 7.5 L. - Method of holding animals in test chamber: body plethysmographs. - Atmosphere ... sample volume: 90 - 400 mL; sample frequency: 1 sample per concentration group, 2 samples for the highest concentration group) ...
The Effect of Bispectral Index Monitoring on End-Tidal Gas Concentration and Recovery Duration After Outpatient Anesthesia. ... 2010 Volume 30 Number 1. Abstract. In a prospective randomized study the Bispectral index (BIS) was used to titrate propofol ...
Processed datasets are saved as csv files containing: time [s]; pressure [cmH2O]; flow [L/s]; tidal volume [L]; inspiratory ... combine inspiratory and expiratory data into comprehensive breath sets and compute tidal volumes. Example plots of data are ... Pressure, flow and volume can be used as inputs to pulmonary mechanics models to assess their fit and accuracy in identifying ... Lung volume is also increased by external intercostal contraction, which raises the ribcage [4, 5]. Expiration is predominantly ...
... inspiratory reserve volume; VT: tidal volume (TV); ERV: expiratory reserve volume; RV: residual volume; IC: inspiratory ... inspiratory reserve volume; VT: tidal volume (TV); RV: residual volume. ... The volume of gas inhaled or exhaled during the respiratory cycle is called the tidal volume (TV or VT). ... The inspiratory reserve volume is the maximum volume of gas that can be inhaled from the end-inspiratory level during tidal ...
... inspiratory reserve volume; VT: tidal volume (TV); ERV: expiratory reserve volume; RV: residual volume; IC: inspiratory ... inspiratory reserve volume; VT: tidal volume (TV); RV: residual volume. ... The volume of gas inhaled or exhaled during the respiratory cycle is called the tidal volume (TV or VT). ... The inspiratory reserve volume is the maximum volume of gas that can be inhaled from the end-inspiratory level during tidal ...
Critical Care Alert: Low Tidal Volume Ventilation for Emergency Department Patients 6/2/2022 Michael Franczak, MD , Taylor ... Patient volume at the University of Maryland Medical Center is approximately 55,000 per year. ...
... tidal volume, minute ventilation, heart rate, mean arterial and indirect blood pressures, and end-tidal Pco 2 measured every 5 ... Results-Respiratory rate was higher, tidal volume lower, and minute ventilation not different in lateral versus dorsal ... Conclusions and Clinical Relevance-Differences in tidal volume with similar minute ventilation suggested red-tailed hawks in ... Lung volume, lung density, and air-sac volume were calculated from helical computed tomographic (CT) images by use of software ...
However, excessive tidal volumes and inadequate lung recruitment may contrib... Authors: Jean-Jacques Rouby and Qin Lu ...
  • Tidal volume plays a significant role during mechanical ventilation to ensure adequate ventilation without causing trauma to the lungs. (wikipedia.org)
  • Tidal volume is measured in milliliters and ventilation volumes are estimated based on a patient's ideal body mass. (wikipedia.org)
  • Ventilator-induced lung injury such as Acute lung injury (ALI) /Acute Respiratory Distress Syndrome (ARDS) can be caused by ventilation with very large tidal volumes in normal lungs, as well as ventilation with moderate or small volumes in previously injured lungs, and research shows that the incidence of ALI increases with higher tidal volume settings in nonneurologically impaired patients. (wikipedia.org)
  • Similarly A 2018 systematic review by The Cochrane Collaboration provided evidence that low tidal volume ventilation reduced post operative pneumonia and reduced the requirement for both invasive and non invasive ventilation after surgery Initial settings of mechanical ventilation: Protective lung ventilation strategies should be applied with VT 6ml/kg to 8ml/kg with RR = 12 to 20 and an average starting target minute ventilation of 7 L/min. (wikipedia.org)
  • citation needed][clarification needed] Protective lung volumes apply 6ml/kg to 8ml/kg with a rate high enough for proper alveolar ventilation but does not create or aggravate intrinsic Positive End-Expiry Pressure (PEEP). (wikipedia.org)
  • Traditional approaches to mechanical ventilation use tidal volumes of 10 to 15 ml per kilogram of body weight and may cause stretch-induced lung injury in patients with acute lung injury and the acute respiratory distress syndrome. (nih.gov)
  • We therefore conducted a trial to determine whether ventilation with lower tidal volumes would improve the clinical outcomes in these patients. (nih.gov)
  • In patients with acute lung injury and the acute respiratory distress syndrome, mechanical ventilation with a lower tidal volume than is traditionally used results in decreased mortality and increases the number of days without ventilator use. (nih.gov)
  • Aim The aim was to compare resuscitators' estimates of tidal volume (V T ) and face mask leak with measured values during positive pressure ventilation (PPV) of newborn infants in the delivery room. (bmj.com)
  • Coefficient of variation of V T was greater for low f and volume control-mandatory minute ventilation and pressure control modes. (rcjournal.com)
  • One prevalent approach is ventilation with large tidal volumes. (annarborbonsaisociety.org)
  • This was a RCT of low vs. traditional tidal volume ventilation in 861 patients with acute lung injury. (annarborbonsaisociety.org)
  • 1,9-13 Many surgical patients undergo short-term ventilation with large V T (>10 ml/kg predicted body … There are a number of different measurements and terms which are often used to describe this including tidal volume, inspiratory reserve volume, residual volume, vital … Lung volumes and exercise. (annarborbonsaisociety.org)
  • In case you missed it, that trial showed that low tidal volume ventilation (6 ml/kg IBW) improved mortality from 40% to 31% in patients with established lung … The chart above shows volume of the lungs as a function of time. (annarborbonsaisociety.org)
  • LARGE tidal volumes (V T) contribute to and worsen the acute respiratory distress syndrome (ARDS) in intensive care unit (ICU) patients after hours or days of ventilation. (annarborbonsaisociety.org)
  • Figure 1- Effect of lung mechanics and inspiratory time on tidal volume (V T) delivery during high-frequency oscillatory ventilation.a) Maximum potential V T is determined by lung compliance (C L) and inspiratory time (t I), while the rate of V T delivery is determined by lung mechanics. (annarborbonsaisociety.org)
  • To the Editor The inherent physiological rationale for lowering tidal volume during mechanical ventilation is to decrease strain on the lung tissue to avoid ventilator-induced lung injury. (annarborbonsaisociety.org)
  • Importance In patients who undergo mechanical ventilation during surgery, the ideal tidal volume is unclear. (annarborbonsaisociety.org)
  • Forced expiratory volume in one second (FEV1): Forced expiratory volume in one second measures the total amount of air that can be forcibly exhaled in the first second of the FVC test.Healthy people generally expel around 75% … Objective To determine whether low-tidal-volume ventilation compared with conventional ventilation during major surgery decreases postoperative pulmonary complications. (annarborbonsaisociety.org)
  • Analysis from 1,019 patients undergoing one-lung ventilation indicated that low tidal volume in the presence of low positive end-expiratory pressure is associated with increased pulmonary complications. (annarborbonsaisociety.org)
  • There are 3 main ways auto-PEEP occurs: 1) High minute ventilation - high respiratory rates or high tidal volumes Similar to pulmonary function tests, these will include tidal breathing (the normal breathing volume), respiratory rate, and vital capacity (breathing volume during a deep breath). (annarborbonsaisociety.org)
  • With the development of safe endotracheal tubes with high-volume, low-pressure cuffs, positive-pressure ventilation replaced the iron lung. (medscape.com)
  • Volume-cycled ventilation is the most common form of ventilator cycling used in adult medicine because it provides a consistent breath-to-breath tidal volume. (medscape.com)
  • Cite this: Few Eligible ARDS Patients Receive Low Tidal Volume Ventilation - Medscape - Aug 30, 2017. (medscape.com)
  • Mechanical ventilation practice has changed over the past few decades, with tidal volumes (VT) decreasing significantly, especially in patients with acute lung injury (ALI). (elsevierpure.com)
  • We tested the hypothesis that the lung-protective ventilation strategy including a low tidal volume, an appropriate level of PEEP and periodic recruitment maneuvers could improve intraoperative oxygenation function, pulmonary mechanics, and early postoperative atelectasis. (springer.com)
  • She was ventilated by pressure-controlled ventilation, volume-guaranteed mode (PCV-VG®, GE Healthcare, Little Chalfont, England) at a tidal volume (TV) of 450 mL, respiratory rate of 12 breaths/min, positive end-expiratory pressure (PEEP) of 5 cmH 2 O, and upper limit of peak inspiratory pressure (PIP) of 30 cmH 2 O, with 50% oxygen. (hindawi.com)
  • When traditional tidal volumes of 10 to 15 mL/kg are used in patients with ALI/ARDS receiving mechanical ventilation, the resulting alveolar pressures are frequently elevated, reflecting over-distention particularly of the less-affected lung regions. (medicosecuador.com)
  • Three small, prospective, randomized trials of traditional versus lower tidal volume ventilation in patients with or at risk for ALI/ARDS did not demonstrate beneficial effects of a modestly lower tidal volume. (medicosecuador.com)
  • Advanced leak compensation in invasive and non-invasive ventilation for pressure modes, as well as volume modes. (dremed.com)
  • AVAPS (Average Volume Assured Pressure Support) hybrid ventilation in pressure modes for invasive and non-invasive modalities. (dremed.com)
  • Trend overviews of the past 12 months displaying: pressure, breath rate, percentage of triggered breaths, peak inspiratory patient flow, estimated exhaled tidal volume, leak, Ti/Ttot and minute ventilation. (dremed.com)
  • The optional ventilator provides electrically-driven automatic ventilation in volume and pressure control modes, and will operate without mains power for up to 6 hours on rechargeable battery power. (engineeringforchange.org)
  • Alveolar minute ventilation is defined by the volume of alveolar gas expired in one-minute. (pharmacology2000.com)
  • In our consideration of anesthetic ventilation systems, the term re- breathing is frequently encountered and refers to a condition in which some of the expired alveolar gas (containing 5% CO 2 ) is inspired in the next tidal volume. (pharmacology2000.com)
  • The anesthesia machine offers advanced ICU Piston ventilation that eliminated the need for driver gases, while still providing support for volume and pressure controls and pressure support. (somatechnology.com)
  • Volume control, pressure control, pressure support (PS) and SIMV/PS - all major ventilation modes can be supported. (somatechnology.com)
  • The primary outcome was the use of low tidal volume ventilation (LTVV) for the first 3 days of mechanical ventilation. (lu.se)
  • As the airway pressure drops to zero, elastic recoil of the chest accomplishes passive exhalation by pushing the tidal volume out. (medscape.com)
  • RV refers to the volume of gas remaining in the lung after maximal exhalation (regardless of the lung volume at which exhalation was started). (ersjournals.com)
  • Sometimes, the test will be preceded by a period of quiet breathing in and out from the sensor (tidal volume), or the rapid breath in (forced inspiratory part) will come before the forced exhalation. (wikidoc.org)
  • 2011). The increased breathing resistances found in EHMRs can result in a decreased frequency of breathing and an increase in tidal volume (the air displaced between normal inhalation and exhalation). (cdc.gov)
  • It measures the forced vital capacity (FVC), the forced exhaled volume in 1 second (FEV1), total lung capacity, and residual volume. (wikidoc.org)
  • What tidal volumes should be used in patients without acute lung injury? (elsevierpure.com)
  • Dive into the research topics of 'What tidal volumes should be used in patients without acute lung injury? (elsevierpure.com)
  • Evidence only proves low surpasses high tidal volume ( V T ) for acute respiratory distress syndrome (ARDS). (medintensiva.org)
  • Tidal volume (symbol VT or TV) is the volume of air moved into or out of the lungs during a normal breath. (wikipedia.org)
  • The total lung capacity (TLC) is the volume of gas that is contained in the lungs at the end of maximal inspiration. (annarborbonsaisociety.org)
  • Inspiratory reserve volume is … Respiratory volumes are the amount of air inhaled, exhaled and stored within the lungs at any given time. (annarborbonsaisociety.org)
  • When normal lungs are ventilated with large tidal volumes (VT) and end-inspired pressures (Pei), surfactant is depleted and pulmonary edema develops. (northwestern.edu)
  • The term "lung volume" usually refers to the volume of gas within the lungs, as measured by body plethysmography, gas dilution or washout. (ersjournals.com)
  • Lung volumes derived from computed tomography (CT) scans can include estimates of abnormal lung tissue volumes, in addition to normal lung tissue volumes and the volume of gas within the lungs. (ersjournals.com)
  • TLC refers to the volume of gas in the lungs after maximal inspiration, or the sum of all volume compartments. (ersjournals.com)
  • This is the total volume of the lungs when filled with as much air as possible. (brighamandwomens.org)
  • Elastic pressure is the product of the elastic recoil of the lungs and chest wall (elastance) and the volume of gas delivered. (msdmanuals.com)
  • The aim of the study was to evaluate the ability of home ventilators to maintain a minimal tidal volume during different conditions associated with alveolar hypoventilation. (nih.gov)
  • The thoracic gas volume (TGV or V TG ) is the absolute volume of gas in the thorax at any point in time and any level of alveolar pressure. (ersjournals.com)
  • Volutrauma is alveolar over-distention due to an excessive inflation volume. (medicosecuador.com)
  • Measurements of absolute lung volumes, residual volume (RV), functional residual capacity (FRC) and total lung capacity (TLC) are technically more challenging, which limits their use in clinical practice. (ersjournals.com)
  • Residual volume. (brighamandwomens.org)
  • Examples of inappropriate LTVV strategies are using plateau pressure but not tidal volume limits, and calculating tidal volume using actual instead of ideal body weight. (medscape.com)
  • The static lung volumes/capacities are further subdivided into four standard volumes (tidal, inspiratory … Forced vital capacity (FVC): Forced vital capacity measures the amount of air you can breathe out forcefully after taking as deep a breath as possible. (annarborbonsaisociety.org)
  • Termination of the delivered breath is signaled when a set volume leaves the ventilator. (medscape.com)
  • Spirometry (meaning the measuring of breath ) is the most common of the Pulmonary Function Tests (PFTs), measuring lung function, specifically the measurement of the amount (volume) and/or speed (flow) of air that can be inhaled and exhaled. (wikidoc.org)
  • Tidal volume increases and , thereafter, breath frequency rises. (cdc.gov)
  • Pressure (P)-volume (V) relationships of the total respiratory system a) in normal and b) in chronic obstructive pulmonary disease (COPD).Tidal P-V curves during rest ( ) and exercise ( ) are shown. (annarborbonsaisociety.org)
  • For a given volume, elastic pressure is increased by increased lung stiffness (as in pulmonary fibrosis) or restricted excursion of the chest wall or diaphragm (as in tense ascites or massive obesity). (msdmanuals.com)
  • It can be assessed with the negative expiratory pressure (NEP) technique and is expressed as either the percentage of the tidal volume over which EFL occurs (EFL%Vt) or according to more detailed three-point or five-point scoring systems. (annarborbonsaisociety.org)
  • The expiratory reserve volume (ERV) is the volume of gas that can be maximally exhaled from the end-expiratory level during tidal breathing ( i.e. from the FRC). (ersjournals.com)
  • Forced expiratory volume. (brighamandwomens.org)
  • The tidal volume is the total amount of air inhaled or exhaled during regular respiration or relaxed breathing. (annarborbonsaisociety.org)
  • The maintenance of a minimal tidal volume during a non-intentional leak was more difficult and was associated with large variations in tidal volume, a default of pressure support delivery for some devices, and patient-ventilator dyssynchrony, both during the bench and the in vivo study. (nih.gov)
  • Limiting tidal volume (V T ) in patients with ARDS may not be achieved once patient-triggered breaths occur. (rcjournal.com)
  • Pressure support with guaranteed volume could be tested in patients with ARDS. (rcjournal.com)
  • In patients with ARDS, it has been shown that setting ventilator tidal volume (V T ) to 6 mL/kg ideal body weight (IBW) actually accommodates a 4-8-mL/kg IBW range, which when set at the ventilator can improve survival. (rcjournal.com)
  • The volume of gas inhaled or exhaled during the respiratory cycle is called the tidal volume (TV or V T ). (ersjournals.com)
  • Few local bands make waves quite like St. Louis "empower pop" band Tidal Volume. (theyoungfolks.com)
  • The long tidal waves do not break, except mabye close to continental shelves. (copernicus.org)
  • In the present manuscript, it is unclear how the long tidal waves would induce mixing, and the issue is not touched at all. (copernicus.org)
  • By review of definitions, the volume of gas inspired and expired with each respiratory cycle is the tidal volume which normalized per kilogram is about 6-10mls/kg. (pharmacology2000.com)
  • Flow-Volume loop showing successful FVC maneuver. (wikidoc.org)
  • This creates problems with air flow, mostly because you have less lung volume. (brighamandwomens.org)
  • Measurement of tidal volume can be affected (usually overestimated) by leaks in the breathing circuit or the introduction of additional gas, for example during the introduction of nebulized drugs. (wikipedia.org)
  • In contrast to the relative simplicity of spirometric volumes, a variety of disparate techniques have been developed for the measurement of absolute lung volumes. (ersjournals.com)
  • The six ventilators were able to maintain a minimal tidal volume during an increase in airway resistance and a decrease in lung compliance. (nih.gov)
  • 6 mL/kg was significantly increased with spontaneous breaths patient-triggered by pressure support (OR 19.36, 95% CI 12.37-30.65) and significantly reduced in APRV (OR 0.44, 95% CI 0.26-0.72) and pressure support with guaranteed volume mode. (rcjournal.com)
  • Nevertheless, in particular circumstances, measurements of lung volume are strictly necessary for a correct physiological diagnosis 1 . (ersjournals.com)
  • The total volume in the respiratory cycle per minute is the minute volume and also by weight definition the functional residual capacity (FRC) is the volume of gas remaining in the lung following normal expiration. (pharmacology2000.com)
  • 6 mL/kg was significantly reduced in APRV and pressure support with guaranteed volume mode. (rcjournal.com)
  • Concepts that the military developed during World War II to deliver oxygen and gas volume to fighter pilots operating at high altitude were incorporated into the design of the modern positive-pressure ventilator. (medscape.com)
  • The signal to terminate the inspiratory activity of the machine is either a preset volume (for a volume-cycled ventilator), a preset pressure limit (for a pressure-cycled ventilator), or a preset time factor (for a time-cycled ventilator). (medscape.com)
  • Servo Compass makes it easy to see when plateau/driving pressure or tidal volume per predicted body weight (VT/PBW) are off pre-defined targets and interventions are needed. (getinge.com)
  • The RV is a thin-walled chamber that is a better volume pump than a pressure pump. (medscape.com)
  • RV pressure and volume overload is associated with septal displacement toward the left ventricle. (medscape.com)
  • 10-75 L/min in Volume and Pressure Control. (somatechnology.com)
  • Static lung volumes and capacities based on a volume-time spirogram of an inspiratory vital capacity (IVC). (ersjournals.com)
  • The maximum volume of gas that can be inspired from FRC is referred to as the inspiratory capacity (IC). (ersjournals.com)
  • The vital capacity (VC) is the volume change at the mouth between the positions of full inspiration and complete expiration. (ersjournals.com)
  • Other tests used for restrictive lung patterns along with spirometry are helium lung volumes and diffusing capacity of carbon monoxide. (wikidoc.org)
  • However, excessive tidal volumes and inadequate lung recruitment may contrib. (biomedcentral.com)
  • To further investigate the tidal volume (VT) response to exercise in severe COPD, nine patients were … In COPD individuals, there is a resetting of the respiratory system's relaxation volume to a higher level than in the healthy individuals. (annarborbonsaisociety.org)
  • We read with extreme interest the recently published work by O'Donnell and colleagues (May 2010).1 Comparing lung volumes obtained using different techniques in a sample of patients with severe airflow limitation, the authors conclude that plethysmography systematically overestimates lung volumes with regard to gas dilution and thoracic imaging techniques. (annarborbonsaisociety.org)
  • In contrast, lung volumes derived from conventional chest radiographs are usually based on the volumes within the outlines of the thoracic cage, and include the volume of tissue (normal and abnormal), as well as the lung gas volume. (ersjournals.com)
  • Normal tidal volumes are much smaller in newborn, infants, and children, down to 150 ml due to their smaller lung sizes. (annarborbonsaisociety.org)
  • Severe injuries to the central nervous system that result in abolished or very high respiratory drive, for whom it is not possible to maintain protective tidal volume. (who.int)
  • Air fistula or barotrauma that prevents adequate tidal volume monitoring. (who.int)
  • Inspired and expired lung volumes measured by spirometry are useful for detecting, characterising and quantifying the severity of lung disease. (ersjournals.com)
  • Chest wall volumes and respiratory muscle activity were assessed with optoelectronic plethysmography and surface electromyography, respectively. (frontiersin.org)
  • The role of lung volume measurements in the assessment of disease severity, functional disability, course of disease and response to treatment remains to be determined in infants, as well as in children and adults. (ersjournals.com)
  • the large VT was chosen to match Pei and end-spired lung volume. (northwestern.edu)
  • In a healthy, young human adult, tidal volume is approximately 500 ml per inspiration or 7 ml/kg of body mass. (wikipedia.org)
  • Since this term is too nonspecific, it is recommended that its use should be discontinued and replaced with more specific terminology, for example, plethysmographic lung volume (abbreviated at V L,pleth ), and FRC by body plethysmography or TGV at FRC (FRC pleth ). (ersjournals.com)
  • Children exposed to the same levels of acrolein vapor as adults may receive a larger dose because they have greater lung surface area:body weight ratios and higher minute volumes:weight ratios. (cdc.gov)