Inflation, Economic
Pulmonary Stretch Receptors
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.
Lung Volume Measurements
Pressure
Tourniquets
Respiratory Mechanics
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.
Lung
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
Respiration
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).
Vagus Nerve
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).
Catheterization
Functional Residual Capacity
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.
Air Pressure
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.
Lung Compliance
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)
Total Lung Capacity
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.
Reflex
Intercostal Muscles
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)
Gravity Suits
Double-layered inflatable suits which, when inflated, exert pressure on the lower part of the wearer's body. The suits are used to improve or stabilize the circulatory state, i.e., to prevent hypotension, control hemorrhage, and regulate blood pressure. The suits are also used by pilots under positive acceleration.
Insufflation
Angioplasty, Balloon, Coronary
Dilation of an occluded coronary artery (or arteries) by means of a balloon catheter to restore myocardial blood supply.
Dogs
Positive-Pressure Respiration
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.
Ribs
Intercostal Nerves
The ventral rami of the thoracic nerves from segments T1 through T11. The intercostal nerves supply motor and sensory innervation to the thorax and abdomen. The skin and muscles supplied by a given pair are called, respectively, a dermatome and a myotome.
Thoracic Wall
Laryngeal Nerves
Branches of the VAGUS NERVE. The superior laryngeal nerves originate near the nodose ganglion and separate into external branches, which supply motor fibers to the cricothyroid muscles, and internal branches, which carry sensory fibers. The RECURRENT LARYNGEAL NERVE originates more caudally and carries efferents to all muscles of the larynx except the cricothyroid. The laryngeal nerves and their various branches also carry sensory and autonomic fibers to the laryngeal, pharyngeal, tracheal, and cardiac regions.
Respiration, Artificial
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).
Vagotomy
The interruption or removal of any part of the vagus (10th cranial) nerve. Vagotomy may be performed for research or for therapeutic purposes.
Tidal Volume
Mechanoreceptors
Respiratory Physiological Phenomena
Physiological processes and properties of the RESPIRATORY SYSTEM as a whole or of any of its parts.
Phrenic Nerve
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.
Collateral Circulation
Pulmonary Atelectasis
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.
Pulmonary Alveoli
Blood Pressure
PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.
Ischemic Preconditioning, Myocardial
Exposure of myocardial tissue to brief, repeated periods of vascular occlusion in order to render the myocardium resistant to the deleterious effects of ISCHEMIA or REPERFUSION. The period of pre-exposure and the number of times the tissue is exposed to ischemia and reperfusion vary, the average being 3 to 5 minutes.
Intubation, Intratracheal
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.
Pulmonary Ventilation
Respiratory Muscles
Apnea
A transient absence of spontaneous respiration.
Muromegalovirus
Diaphragm
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.
Airway Resistance
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.
Nicorandil
A derivative of the NIACINAMIDE that is structurally combined with an organic nitrate. It is a potassium-channel opener that causes vasodilatation of arterioles and large coronary arteries. Its nitrate-like properties produce venous vasodilation through stimulation of guanylate cyclase.
Thorax
Intermittent Pneumatic Compression Devices
Health Expenditures
Angioplasty, Balloon
Use of a balloon catheter for dilation of an occluded artery. It is used in treatment of arterial occlusive diseases, including renal artery stenosis and arterial occlusions in the leg. For the specific technique of BALLOON DILATION in coronary arteries, ANGIOPLASTY, BALLOON, CORONARY is available.
Laryngeal Masks
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.
Stents
Chloralose
Methacholine Chloride
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)
Chemoreceptor Cells
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.
Pulmonary Gas Exchange
The exchange of OXYGEN and CARBON DIOXIDE between alveolar air and pulmonary capillary blood that occurs across the BLOOD-AIR BARRIER.
Air Sacs
Thin-walled sacs or spaces which function as a part of the respiratory system in birds, fishes, insects, and mammals.
Thoracic Nerves
The twelve spinal nerves on each side of the thorax. They include eleven INTERCOSTAL NERVES and one subcostal nerve. Both sensory and motor, they supply the muscles and skin of the thoracic and abdominal walls.
Electrocardiography
Recording of the moment-to-moment electromotive forces of the HEART as projected onto various sites on the body's surface, delineated as a scalar function of time. The recording is monitored by a tracing on slow moving chart paper or by observing it on a cardioscope, which is a CATHODE RAY TUBE DISPLAY.
Bronchoconstriction
Narrowing of the caliber of the BRONCHI, physiologically or as a result of pharmacological intervention.
Artificial Organs
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).
Bronchi
The larger air passages of the lungs arising from the terminal bifurcation of the TRACHEA. They include the largest two primary bronchi which branch out into secondary bronchi, and tertiary bronchi which extend into BRONCHIOLES and PULMONARY ALVEOLI.
Heart Rate
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
Stress, Mechanical
Carbon Dioxide
A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.
Pleural Cavity
Biomechanical Phenomena
Hemodynamics
Splanchnic Nerves
The major nerves supplying sympathetic innervation to the abdomen. The greater, lesser, and lowest (or smallest) splanchnic nerves are formed by preganglionic fibers from the spinal cord which pass through the paravertebral ganglia and then to the celiac ganglia and plexuses. The lumbar splanchnic nerves carry fibers which pass through the lumbar paravertebral ganglia to the mesenteric and hypogastric ganglia.
Anesthesia
Anesthesia, General
Hexamethonium Compounds
Vascular Resistance
The force that opposes the flow of BLOOD through a vascular bed. It is equal to the difference in BLOOD PRESSURE across the vascular bed divided by the CARDIAC OUTPUT.
Esophagus
The muscular membranous segment between the PHARYNX and the STOMACH in the UPPER GASTROINTESTINAL TRACT.
Gastric Balloon
An inflatable device implanted in the stomach as an adjunct to therapy of morbid obesity. Specific types include the silicone Garren-Edwards Gastric Bubble (GEGB), approved by the FDA in 1985, and the Ballobes Balloon.
Inspiratory Capacity
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.
Hexamethonium
A nicotinic cholinergic antagonist often referred to as the prototypical ganglionic blocker. It is poorly absorbed from the gastrointestinal tract and does not cross the blood-brain barrier. It has been used for a variety of therapeutic purposes including hypertension but, like the other ganglionic blockers, it has been replaced by more specific drugs for most purposes, although it is widely used a research tool.
Respiratory Distress Syndrome, Adult
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.
Atropine
An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.
Coronary Disease
An imbalance between myocardial functional requirements and the capacity of the CORONARY VESSELS to supply sufficient blood flow. It is a form of MYOCARDIAL ISCHEMIA (insufficient blood supply to the heart muscle) caused by a decreased capacity of the coronary vessels.
Cost Control
The containment, regulation, or restraint of costs. Costs are said to be contained when the value of resources committed to an activity is not considered excessive. This determination is frequently subjective and dependent upon the specific geographic area of the activity being measured. (From Dictionary of Health Services Management, 2d ed)
Brain Death
A state of prolonged irreversible cessation of all brain activity, including lower brain stem function with the complete absence of voluntary movements, responses to stimuli, brain stem reflexes, and spontaneous respirations. Reversible conditions which mimic this clinical state (e.g., sedative overdose, hypothermia, etc.) are excluded prior to making the determination of brain death. (From Adams et al., Principles of Neurology, 6th ed, pp348-9)
Blood Flow Velocity
Sclera
The white, opaque, fibrous, outer tunic of the eyeball, covering it entirely excepting the segment covered anteriorly by the cornea. It is essentially avascular but contains apertures for vessels, lymphatics, and nerves. It receives the tendons of insertion of the extraocular muscles and at the corneoscleral junction contains the canal of Schlemm. (From Cline et al., Dictionary of Visual Science, 4th ed)
Angina Pectoris
The symptom of paroxysmal pain consequent to MYOCARDIAL ISCHEMIA usually of distinctive character, location and radiation. It is thought to be provoked by a transient stressful situation during which the oxygen requirements of the MYOCARDIUM exceed that supplied by the CORONARY CIRCULATION.
Ventilators, Mechanical
Mechanical devices used to produce or assist pulmonary ventilation.
Pulmonary Emphysema
Enlargement of air spaces distal to the TERMINAL BRONCHIOLES where gas-exchange normally takes place. This is usually due to destruction of the alveolar wall. Pulmonary emphysema can be classified by the location and distribution of the lesions.
Myocardial Ischemia
A disorder of cardiac function caused by insufficient blood flow to the muscle tissue of the heart. The decreased blood flow may be due to narrowing of the coronary arteries (CORONARY ARTERY DISEASE), to obstruction by a thrombus (CORONARY THROMBOSIS), or less commonly, to diffuse narrowing of arterioles and other small vessels within the heart. Severe interruption of the blood supply to the myocardial tissue may result in necrosis of cardiac muscle (MYOCARDIAL INFARCTION).
Coronary Angiography
Radiography of the vascular system of the heart muscle after injection of a contrast medium.
Costs and Cost Analysis
Coronary Circulation
Surface Tension
Chest Wall Oscillation
A respiratory support system used to remove mucus and clear airway by oscillating pressure on the chest.
Swine
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Suction
The removal of secretions, gas or fluid from hollow or tubular organs or cavities by means of a tube and a device that acts on negative pressure.
Scleritis
Refers to any inflammation of the sclera including episcleritis, a benign condition affecting only the episclera, which is generally short-lived and easily treated. Classic scleritis, on the other hand, affects deeper tissue and is characterized by higher rates of visual acuity loss and even mortality, particularly in necrotizing form. Its characteristic symptom is severe and general head pain. Scleritis has also been associated with systemic collagen disease. Etiology is unknown but is thought to involve a local immune response. Treatment is difficult and includes administration of anti-inflammatory and immunosuppressive agents such as corticosteroids. Inflammation of the sclera may also be secondary to inflammation of adjacent tissues, such as the conjunctiva.
Venous Pressure
The blood pressure in the VEINS. It is usually measured to assess the filling PRESSURE to the HEART VENTRICLE.
Treatment Outcome
Trachea
The cartilaginous and membranous tube descending from the larynx and branching into the right and left main bronchi.
Pressoreceptors
Receptors in the vascular system, particularly the aorta and carotid sinus, which are sensitive to stretch of the vessel walls.
Whales, Pilot
Cats
The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)
Afferent Pathways
Residual Volume
Medulla Oblongata
The lower portion of the BRAIN STEM. It is inferior to the PONS and anterior to the CEREBELLUM. Medulla oblongata serves as a relay station between the brain and the spinal cord, and contains centers for regulating respiratory, vasomotor, cardiac, and reflex activities.
Compliance
Distensibility measure of a chamber such as the lungs (LUNG COMPLIANCE) or bladder. Compliance is expressed as a change in volume per unit change in pressure.
Pulmonary Edema
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.
Partial Pressure
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)
Air Bags
Forearm
Part of the arm in humans and primates extending from the ELBOW to the WRIST.
Catheters
Manometry
Measurement of the pressure or tension of liquids or gases with a manometer.
Respiratory Function Tests
Measurement of the various processes involved in the act of respiration: inspiration, expiration, oxygen and carbon dioxide exchange, lung volume and compliance, etc.
Insurance, Physician Services
Masks
Lung Injury
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.
Equipment Failure
Models, Anatomic
Fee Schedules
Fiber Optic Technology
Carotid Sinus
The dilated portion of the common carotid artery at its bifurcation into external and internal carotids. It contains baroreceptors which, when stimulated, cause slowing of the heart, vasodilatation, and a fall in blood pressure.
Carnivora
Muscle Contraction
A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.
Coronary Stenosis
Narrowing or constriction of a coronary artery.
Muscle Tonus
Electromyography
Vectorcardiography
Recording of the moment-to-moment electromotive forces of the heart on a plane of the body surface delineated as a vector function of time.
Pulmonary Artery
United States
The term "United States" in a medical context often refers to the country where a patient or study participant resides, and is not a medical term per se, but relevant for epidemiological studies, healthcare policies, and understanding differences in disease prevalence, treatment patterns, and health outcomes across various geographic locations.
Sheep
Synchrotrons
Analysis of Variance
Rabbits
Tracheostomy
Surgical formation of an opening into the trachea through the neck, or the opening so created.
Computer Simulation
Biguanides
Respiratory System
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.
Rats, Sprague-Dawley
Stomach
An organ of digestion situated in the left upper quadrant of the abdomen between the termination of the ESOPHAGUS and the beginning of the DUODENUM.
Pyloric Antrum
Models, Biological
Intracranial Pressure
Intubation, Gastrointestinal
The insertion of a tube into the stomach, intestines, or other portion of the gastrointestinal tract to allow for the passage of food products, etc.
Brachial Artery
The continuation of the axillary artery; it branches into the radial and ulnar arteries.
Assisted Circulation
Pumping that aids the natural activity of the heart. (Dorland, 27th ed)
Models, Cardiovascular
Ultrasonography, Interventional
Therapeutic Irrigation
Tomography, X-Ray Computed
Drug-Eluting Stents
Pylorus
The region of the STOMACH at the junction with the DUODENUM. It is marked by the thickening of circular muscle layers forming the pyloric sphincter to control the opening and closure of the lumen.
Hyperventilation
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.
Premedication
Preliminary administration of a drug preceding a diagnostic, therapeutic, or surgical procedure. The commonest types of premedication are antibiotics (ANTIBIOTIC PROPHYLAXIS) and anti-anxiety agents. It does not include PREANESTHETIC MEDICATION.
Respiratory Distress Syndrome, Newborn
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.
Muscle, Smooth
Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)
Pentobarbital
A short-acting barbiturate that is effective as a sedative and hypnotic (but not as an anti-anxiety) agent and is usually given orally. It is prescribed more frequently for sleep induction than for sedation but, like similar agents, may lose its effectiveness by the second week of continued administration. (From AMA Drug Evaluations Annual, 1994, p236)
Monitoring, Physiologic
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.
Oxygen
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.
Prospective Studies
Blood Gas Analysis
Respiratory Therapy
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.
Budgets
Action Potentials
Myocardial Infarction
NECROSIS of the MYOCARDIUM caused by an obstruction of the blood supply to the heart (CORONARY CIRCULATION).
Reproducibility of Results
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.
Arteries
The vessels carrying blood away from the heart.
Intermittent Positive-Pressure Ventilation
Application of positive pressure to the inspiratory phase when the patient has an artificial airway in place and is connected to a ventilator.
Carotid Body
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.
Urethane
Antineoplastic agent that is also used as a veterinary anesthetic. It has also been used as an intermediate in organic synthesis. Urethane is suspected to be a carcinogen.
Peristalsis
A movement, caused by sequential muscle contraction, that pushes the contents of the intestines or other tubular organs in one direction.