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)
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)
Part of the arm in humans and primates extending from the ELBOW to the WRIST.
The flow of BLOOD through or around an organ or region of the body.
The inferior part of the lower extremity between the KNEE and the ANKLE.
A competitive inhibitor of nitric oxide synthetase.
The physiological widening of BLOOD VESSELS by relaxing the underlying VASCULAR SMOOTH MUSCLE.
A powerful vasodilator used in emergencies to lower blood pressure or to improve cardiac function. It is also an indicator for free sulfhydryl groups in proteins.
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.
Measurement of the amount of air that the lungs may contain at various points in the respiratory cycle.
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)
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 vessels carrying blood away from the capillary beds.
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).
The presence of an increased amount of blood in a body part or an organ leading to congestion or engorgement of blood vessels. Hyperemia can be due to increase of blood flow into the area (active or arterial), or due to obstruction of outflow of blood from the area (passive or venous).
Drugs used to cause dilation of the blood vessels.
The volume of air inspired or expired during each normal, quiet respiratory cycle. Common abbreviations are TV or V with subscript T.
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 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.
The outer margins of the thorax containing SKIN, deep FASCIA; THORACIC VERTEBRAE; RIBS; STERNUM; and MUSCLES.
The total volume of gas inspired or expired per unit of time, usually measured in liters per minute.
The blood pressure in the VEINS. It is usually measured to assess the filling PRESSURE to the HEART VENTRICLE.
Regional infusion of drugs via an arterial catheter. Often a pump is used to impel the drug through the catheter. Used in therapy of cancer, upper gastrointestinal hemorrhage, infection, and peripheral vascular disease.
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)
An occupational disorder resulting from prolonged exposure to vibration, affecting the fingers, hands, and forearms. It occurs in workers who regularly use vibrating tools such as jackhammers, power chain saws, riveters, etc. Symptoms include episodic finger blanching, NUMBNESS, tingling, and loss of nerve sensitivity.
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.
Impaired venous blood flow or venous return (venous stasis), usually caused by inadequate venous valves. Venous insufficiency often occurs in the legs, and is associated with EDEMA and sometimes with VENOUS STASIS ULCERS at the ankle.
The measure of a BLOOD VESSEL's ability to increase the volume of BLOOD it holds without a large increase in BLOOD PRESSURE. The vascular capacitance is equal to the change in volume divided by the change in pressure.
A condition characterized by a chronically swollen limb, often a leg with stasis dermatitis and ulcerations. This syndrome can appear soon after phlebitis or years later. Postphlebitic syndrome is the result of damaged or incompetent venous valves in the limbs. Distended, tortuous VARICOSE VEINS are usually present. Leg pain may occur after long period of standing.
A neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system.
PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.
Measurement of the various processes involved in the act of respiration: inspiration, expiration, oxygen and carbon dioxide exchange, lung volume and compliance, etc.
A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.
Single pavement layer of cells which line the luminal surface of the entire vascular system and regulate the transport of macromolecules and blood components.
Radiographic visualization or recording of a vein after the injection of contrast medium.
Inflammation of a vein associated with a blood clot (THROMBUS).
The continuation of the axillary artery; it branches into the radial and ulnar arteries.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
Agents causing the narrowing of the lumen of a bronchus or bronchiole.
Any hindrance to the passage of air into and out of the lungs.
Measurement of volume of air inhaled or exhaled by the lung.
Translocation of body fluids from one compartment to another, such as from the vascular to the interstitial compartments. Fluid shifts are associated with profound changes in vascular permeability and WATER-ELECTROLYTE IMBALANCE. The shift can also be from the lower body to the upper body as in conditions of weightlessness.
The physiological narrowing of BLOOD VESSELS by contraction of the VASCULAR SMOOTH MUSCLE.
The mixture of gases present in the earth's atmosphere consisting of oxygen, nitrogen, carbon dioxide, and small amounts of other gases.
The vein formed by the union of the anterior and posterior tibial veins; it courses through the popliteal space and becomes the femoral vein.
The volume of air remaining in the LUNGS at the end of a maximal expiration. Common abbreviation is RV.
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
The position or attitude of the body.
External decompression applied to the lower body. It is used to study orthostatic intolerance and the effects of gravitation and acceleration, to produce simulated hemorrhage in physiologic research, to assess cardiovascular function, and to reduce abdominal stress during childbirth.
A transient absence of spontaneous respiration.
The act of BREATHING in.
Studies comparing two or more treatments or interventions in which the subjects or patients, upon completion of the course of one treatment, are switched to another. In the case of two treatments, A and B, half the subjects are randomly allocated to receive these in the order A, B and half to receive them in the order B, A. A criticism of this design is that effects of the first treatment may carry over into the period when the second is given. (Last, A Dictionary of Epidemiology, 2d ed)
Volume of circulating BLOOD. It is the sum of the PLASMA VOLUME and ERYTHROCYTE VOLUME.
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)
The vein accompanying the femoral artery in the same sheath; it is a continuation of the popliteal vein and becomes the external iliac vein.
The neural systems which act on VASCULAR SMOOTH MUSCLE to control blood vessel diameter. The major neural control is through the sympathetic nervous system.
A clinical manifestation of abnormal increase in the amount of carbon dioxide in arterial blood.
An idiopathic vascular disorder characterized by bilateral Raynaud phenomenon, the abrupt onset of digital paleness or CYANOSIS in response to cold exposure or stress.
Drugs used to cause constriction of the blood vessels.
A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.
The posture of an individual lying face up.
A volatile vasodilator which relieves ANGINA PECTORIS by stimulating GUANYLATE CYCLASE and lowering cytosolic calcium. It is also sometimes used for TOCOLYSIS and explosives.
The TEMPERATURE at the outer surface of the body.
Enlarged and tortuous VEINS.
The measurement of frequency or oscillation changes.
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.
Four or five slender jointed digits in humans and primates, attached to each HAND.
These include the muscles of the DIAPHRAGM and the INTERCOSTAL MUSCLES.
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.
Narrowing of the caliber of the BRONCHI, physiologically or as a result of pharmacological intervention.
The relationship between the dose of an administered drug and the response of the organism to the drug.
The blood pressure in the central large VEINS of the body. It is distinguished from peripheral venous pressure which occurs in an extremity.
Skin breakdown or ulceration caused by VARICOSE VEINS in which there is too much hydrostatic pressure in the superficial venous system of the leg. Venous hypertension leads to increased pressure in the capillary bed, transudation of fluid and proteins into the interstitial space, altering blood flow and supply of nutrients to the skin and subcutaneous tissues, and eventual ulceration.
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
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.
The thoracolumbar division of the autonomic nervous system. Sympathetic preganglionic fibers originate in neurons of the intermediolateral column of the spinal cord and project to the paravertebral and prevertebral ganglia, which in turn project to target organs. The sympathetic nervous system mediates the body's response to stressful situations, i.e., the fight or flight reactions. It often acts reciprocally to the parasympathetic system.
Relatively complete absence of oxygen in one or more tissues.
A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.
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.
The movement of the BLOOD as it is pumped through the CARDIOVASCULAR SYSTEM.
Delivery of drugs into an artery.
The number of times an organism breathes with the lungs (RESPIRATION) per unit time, usually per minute.
That portion of the body that lies between the THORAX and the PELVIS.
Plethysmographic determination in which the intensity of light reflected from the skin surface and the red cells below is measured to determine the blood volume of the respective area. There are two types, transmission and reflectance.
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.
A standard and widely accepted diagnostic test used to identify patients who have a vasodepressive and/or cardioinhibitory response as a cause of syncope. (From Braunwald, Heart Disease, 7th ed)
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.
The relative amounts of various components in the body, such as percentage of body fat.
Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.
Devices for the compression of a blood vessel by application around an extremity to control the circulation and prevent the flow of blood to or from the distal area. (From Dorland, 28th ed)
The rate of airflow measured during a FORCED VITAL CAPACITY determination.
Ultrasonography applying the Doppler effect combined with real-time imaging. The real-time image is created by rapid movement of the ultrasound beam. A powerful advantage of this technique is the ability to estimate the velocity of flow from the Doppler shift frequency.
Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.
A vein on either side of the body which is formed by the union of the external and internal iliac veins and passes upward to join with its fellow of the opposite side to form the inferior vena cava.
A short-acting beta-2 adrenergic agonist that is primarily used as a bronchodilator agent to treat ASTHMA. Albuterol is prepared as a racemic mixture of R(-) and S(+) stereoisomers. The stereospecific preparation of R(-) isomer of albuterol is referred to as levalbuterol.
Elements of limited time intervals, contributing to particular results or situations.
The volume of air that is exhaled by a maximal expiration following a maximal inspiration.
The vessels carrying blood away from the heart.
Agents that cause an increase in the expansion of a bronchus or bronchial tubes.
An NADPH-dependent enzyme that catalyzes the conversion of L-ARGININE and OXYGEN to produce CITRULLINE and NITRIC OXIDE.
A nonapeptide messenger that is enzymatically produced from KALLIDIN in the blood where it is a potent but short-lived agent of arteriolar dilation and increased capillary permeability. Bradykinin is also released from MAST CELLS during asthma attacks, from gut walls as a gastrointestinal vasodilator, from damaged tissues as a pain signal, and may be a neurotransmitter.
Physical activity which is usually regular and done with the intention of improving or maintaining PHYSICAL FITNESS or HEALTH. Contrast with PHYSICAL EXERTION which is concerned largely with the physiologic and metabolic response to energy expenditure.
Material used for wrapping or binding any part of the body.
Tendency of the smooth muscle of the tracheobronchial tree to contract more intensely in response to a given stimulus than it does in the response seen in normal individuals. This condition is present in virtually all symptomatic patients with asthma. The most prominent manifestation of this smooth muscle contraction is a decrease in airway caliber that can be readily measured in the pulmonary function laboratory.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
Tests involving inhalation of allergens (nebulized or in dust form), nebulized pharmacologically active solutions (e.g., histamine, methacholine), or control solutions, followed by assessment of respiratory function. These tests are used in the diagnosis of asthma.
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)
A subtype of endothelin receptor found predominantly in the VASCULAR SMOOTH MUSCLE. It has a high affinity for ENDOTHELIN-1 and ENDOTHELIN-2.
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.
Muscles forming the ABDOMINAL WALL including RECTUS ABDOMINIS, external and internal oblique muscles, transversus abdominis, and quadratus abdominis. (from Stedman, 25th ed)
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
The farthest or outermost projections of the body, such as the HAND and FOOT.
The act of constricting.
The formation or presence of a blood clot (THROMBUS) within a vein.
An abnormally low volume of blood circulating through the body. It may result in hypovolemic shock (see SHOCK).
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)

Peripheral hemodynamics evaluated by acceleration plethysmography in workers exposed to lead. (1/1109)

To clarify the effect of lead exposure on peripheral hemodynamics, acceleration plethysmography (APG) was performed for 48 male subjects occupationally exposed to lead (exposure group) and 43 male subjects with no history of occupational exposure to lead (control group). In the exposure group, the blood lead concentration (Pb-B) was also measured. Each APG parameter was assessed by comparing measured data with the standard aging curves. A significant negative correlation was obtained between the parameter--b/a and Pb-B. The exposure group showed significantly lower values of parameters--b/a (p < 0.01) and d/a (p < 0.05) than the control group. The parameter--b/a in the exposure group dose-dependently decreased with increases in length of working career (duration of exposure to lead) and Pb-B. The parameter--b/a significantly (p < 0.05) decreased in subjects with working careers of 5 years or more and in subjects whose Pb-B was 40 micrograms/100 ml or more. These results suggest that lead exposure affects peripheral hemodynamics as evaluated by APG.  (+info)

Effect of intensive therapy for heart failure on the vasodilator response to exercise. (2/1109)

OBJECTIVES: The purpose of the study was to evaluate the lower extremity vascular responsiveness to metabolic stimuli in patients with heart failure and to determine whether these responses improve acutely after intensive medical therapy. BACKGROUND: Metabolic regulation of vascular tone is an important determinant of blood flow, and may be abnormal in heart failure. METHODS: The leg blood flow responses were measured in 11 patients with nonedematous class III-IV heart failure before and after inpatient medical therapy and in 10 normal subjects. Venous occlusion plethysmography was used to measure peak blood flow and total hyperemia in the calf after arterial occlusion and also after isotonic ankle exercise. Measurements were repeated following short-term inpatient treatment with vasodilators and diuretics administered to decrease right atrial pressure (18+/-2 to 7+/-1 mm Hg), pulmonary wedge pressure (32+/-3 to 15+/-2 mm Hg), and systemic vascular resistance (1581+/-200 to 938+/-63 dynes.s.cm(-5), all p < 0.02). RESULTS: Leg blood flow at rest, after exercise, and during reactive hyperemia was less in heart failure patients than in control subjects. Resting leg blood flow did not increase significantly after medical therapy, but peak flow after the high level of exercise increased by 59% (p = 0.009). Total hyperemic volume in the recovery period increased by 73% (p = 0.03). Similarly, the peak leg blood flow response to ischemia increased by 88% (p = 0.04), whereas hyperemic volume rose by 98% (p = 0.1). CONCLUSIONS: The calf blood flow responses to metabolic stimuli are blunted in patients with severe heart failure, and improve rapidly with intensive medical therapy.  (+info)

Endothelium-dependent relaxation by acetylcholine is impaired in hypertriglyceridemic humans with normal levels of plasma LDL cholesterol. (3/1109)

OBJECTIVES: Patients with high triglyceride (of which very low density lipoproteins [VLDL] are the main carriers), but with normal low density lipoprotein (LDL) cholesterol levels, were examined for in vivo endothelium function status. BACKGROUND: Very low density lipoproteins inhibit endothelium-dependent, but not -independent, vasorelaxation in vitro. METHODS: Three groups were studied: 1) healthy volunteers (n = 10; triglyceride 1.24+/-0.14 mmol/liter, LDL cholesterol 2.99+/-0.24 mmol/liter); 2) hypertriglyceridemic (n = 11; triglyceride 6.97+/-1.19 mmol/liter, LDL cholesterol 2.17+/-0.2 mmol/liter, p < 0.05); and 3) hypercholesterolemic (n = 10; triglyceride 2.25+/-0.29 mmol/liter, LDL cholesterol 5.61+/-0.54 mmol/liter; p < 0.05) patients. Vasoactive responses to acetylcholine, sodium nitroprusside, noradrenaline, N(G)-monomethyl-L-arginine and postischemic hyperemia were determined using forearm venous occlusion plethysmography. RESULTS: Responses to acetylcholine (37 microg/min) were significantly dampened both in hypercholesterolemic (% increase in forearm blood flow: 268.2+/-62) and hypertriglyceridemic patients (232.6+/-45.2) when compared with controls (547.8+/-108.9; ANOVA p < 0.05). Responses to sodium nitroprusside (at 1.6 microg/min: controls vs. hypercholesterolemics vs. hypertriglyceridemic: 168.7+/- 25.1 vs. 140.6+/-38.9 vs. 178.5+/-54.5% increase), noradrenaline, N(G)-monomethyl-L-arginine and postischemic hyperemic responses were not different among the groups examined. CONCLUSIONS: Acetylcholine responses are impaired in patients with pathophysiologic levels of plasma triglycerides but normal plasma levels of LDL cholesterol. The impairment observed was comparable to that obtained in hypercholesterolemic patients. We conclude that impaired responses to acetylcholine normally associated with hypercholesterolemia also occur in hypertriglyceridemia. These findings identify a potential mechanism by which high plasma triglyceride levels may be atherogenic independent of LDL cholesterol levels.  (+info)

Endothelial dysfunction, impaired endogenous fibrinolysis, and cigarette smoking: a mechanism for arterial thrombosis and myocardial infarction. (4/1109)

BACKGROUND: Effective endogenous fibrinolysis requires rapid release of tissue plasminogen activator (tPA) from the vascular endothelium. Smoking is a known risk factor for arterial thrombosis and myocardial infarction, and it causes endothelial dysfunction. We therefore examined the effects of cigarette smoking on substance P-induced tPA release in vivo in humans. METHODS AND RESULTS: Blood flow and plasma fibrinolytic factors were measured in both forearms of 12 smokers and 12 age- and sex-matched nonsmokers who received unilateral brachial artery infusions of substance P (2 to 8 pmol/min). In both smokers and nonsmokers, substance P caused dose-dependent increases in blood flow and local release of plasma tPA antigen and activity (P<0.001 for all) but had no effect on the local release of plasminogen activator inhibitor type 1. Compared with nonsmokers, increases in forearm blood flow (P=0.03) and release of tPA antigen (P=0.04) and activity (P<0.001) caused by substance P were reduced in smokers. The area under the curve for release of tPA antigen and activity decreased by 51% and 53%, respectively. CONCLUSIONS: Cigarette smoking causes marked inhibition of substance P-induced tPA release in vivo in humans. This provides an important mechanism whereby endothelial dysfunction may increase the risk of atherothrombosis through a reduction in the acute fibrinolytic capacity.  (+info)

Comparison of two new methods for the measurement of lung volumes with two standard methods. (5/1109)

BACKGROUND: The two most commonly used methods for the measurement of lung volumes are helium dilution and body plethysmography. Two methods have been developed which are both easier and less time consuming to perform. Mathematical modelling uses complex calculations from the flow-volume loop to derive total lung capacity (TLC), and the nitrogen balance technique uses nitrogen from the atmosphere to calculate lung volume in a similar way to helium dilution. This study was designed to compare the two new methods with the two standard methods. METHODS: Sixty one subjects were studied, 23 with normal lung function, 17 with restrictive airway disease, and 21 with obstructive ventilatory defects. Each subject underwent repeated measurements of TLC by each of the four methods in random order. Reproducible values were obtained for each method according to BTS/ARTP guidelines. Bland-Altman plots were constructed for comparisons between the methods and paired t tests were used to assess differences in means. RESULTS: Bland-Altman plots showed that the differences between body plethysmography and helium dilution fell into clinically acceptable ranges (agreement limits +/-0.9 l). The agreement between mathematical modelling or the nitrogen balance technique and helium dilution or body plethysmography was poor (+/-1.8-3.4 l), especially for subjects with airflow obstruction. CONCLUSIONS: Neither of the new methods agrees sufficiently with standard methods to be useful in a clinical setting.  (+info)

Physiologic basis and interpretation of common indices of respiratory mechanical function. (6/1109)

Tests of pulmonary mechanical function may be used in determining the prominent site of pulmonary reaction to intervention. Responses may be localized from a knowledge of changes in lung resistance and compliance. A peripheral airway or parenchymal response is characterized by a decrease in lung compliance. A central airway reaction is characterized by an increase in pulmonary resistance. In mixed reactions both parameters may change. In this communication some of the physiologic determinants of pulmonary resistance and compliance are discussed and examples of localized responses given.  (+info)

Contribution of nitric oxide to beta2-adrenoceptor mediated vasodilatation in human forearm arterial vasculature. (7/1109)

AIMS: beta2-adrenoceptor agonists are generally considered to produce endothelium independent vasodilatation through adenylate cyclase. We determined whether nitric oxide contributes to beta2-adrenoceptor vasodilatation in human arterial vasculature. METHODS: Forearm blood flow responses to brachial intra-arterial infusions of ritodrine (2.5-50 microg min(-1)), a selective beta2-adrenoceptor agonist, were determined in 24 healthy, normotensive subjects (mean age 22 years, 5F) on two occasions with initial and concomitant administration of L-NMMA (800 microg min(-1)), an NO synthase inhibitor, or noradrenaline (5-30 ng min(-1)), a control constrictor not affecting basal NO activity. Responses to the endothelium dependent vasodilator scrotonin (n = 6) and an endothelium independent vasodilator GTN (n = 9) were also determined. RESULTS: Maximal dilatation to ritodrine during L-NMMA infusion (310+/-32%; mean+/-s.e.mean) was reduced compared to that during noradrenaline infusion (417+/-41%, P<0.05), as were summary responses (1023+/-101 vs 1415+/-130; P<0.05). Responses to GTN were unaffected by L-NMMA compared to noradrenaline; max 177+/-26 vs 169+/-20%, 95% CI for difference -33,48; P=0.68; summary response 361+/-51 vs 396+/-37, 95% CI -142,71; P=0.46. Dilator responses to serotonin were reduced by L-NMMA; max 64+/-20 vs 163+/-26%, P<0.01; summary response 129+/-36 vs 293+/-60; P<0.05) and to a greater extent than ritodrine (58+/-7 vs 25+/-14%, P<0.05). CONCLUSIONS: beta2-adrenoceptor mediated vasodilatation in the human forearm has an NO mediated component. The underlying mechanism for this effect is unclear, but flow mediated vasodilatation is unlikely to be responsible.  (+info)

Relationship between left ventricular mass and endothelium-dependent vasodilation in never-treated hypertensive patients. (8/1109)

BACKGROUND: Hypertensive patients are characterized by development of both left ventricular hypertrophy (LVH) and endothelial dysfunction METHODS AND RESULTS: We enrolled 65 never-treated hypertensive patients (36 men and 29 women aged 45.6+/-6.0 years) to assess the possible relationship between echocardiographic left ventricular mass (LVM) and endothelium-dependent vasodilation. Left ventricular measurements were performed at end diastole and end systole according to the recommendations of the American Society of Echocardiography and the Penn Convention. LVM was calculated with the Devereux formula and indexed by body surface area and height raised to the 2.7th power. The endothelial function was tested as responses of forearm vasculature to acetylcholine (ACh), an endothelium-dependent vasodilator (7.5, 15, and 30 microg. mL-1. min-1, each for 5 minutes), and sodium nitroprusside (SNP), an endothelium-independent vasodilator (0.8, 1.6, and 3.2 microg. mL-1. min-1, each for 5 minutes). Drugs were infused into the brachial artery, and forearm blood flow (FBF) was measured by strain-gauge plethysmography. A negative significant relationship between indexed LVM and peak of increase in FBF was found during ACh infusions (r=-0. 554; P<0.0001). In addition, hypertrophic patients had a significantly lower responsive to ACh than patients without LVH (the peak increase in FBF was 9.9+/-3.7 versus 16.1+/-8.1 mL per 100 mL of tissue per minute; P<0.0001). No significant correlation was observed between LVM and FBF during SNP infusion. CONCLUSIONS: Our data provide the first evidence that echocardiographic LVM in hypertensive patients is inversely related to FBF responses to the endothelium-dependent vasodilating agent ACh, but it is likely that both endothelium and LVM are damaged by hypertension.  (+info)

In some cases, hyperemia can be a sign of a more serious underlying condition that requires medical attention. For example, if hyperemia is caused by an inflammatory or infectious process, it may lead to tissue damage or organ dysfunction if left untreated.

Hyperemia can occur in various parts of the body, including the skin, muscles, organs, and other tissues. It is often diagnosed through physical examination and imaging tests such as ultrasound, computed tomography (CT), or magnetic resonance imaging (MRI). Treatment for hyperemia depends on its underlying cause, and may include antibiotics, anti-inflammatory medications, or surgery.

In the context of dermatology, hyperemia is often used to describe a condition called erythema, which is characterized by redness and swelling of the skin due to increased blood flow. Erythema can be caused by various factors, such as sun exposure, allergic reactions, or skin infections. Treatment for erythema may include topical medications, oral medications, or other therapies depending on its underlying cause.

HAVS is typically caused by prolonged exposure to vibrations from hand-held power tools, such as jackhammers, drills, and sanders. The vibrations can cause damage to the blood vessels, nerves, and joints in the hands, leading to the development of HAVS.

There are several risk factors for developing HAVS, including:

1. Prolonged exposure to hand-transmitted vibrations
2. Use of high-vibration tools and equipment
3. Poor tool maintenance and repair
4. Inadequate training on the safe use of tools and equipment
5. Smoking and other cardiovascular risk factors

The symptoms of HAVS can vary in severity and may include:

1. Numbness, tingling, or pain in the hands and fingers
2. Reduced dexterity and grip strength
3. Fatigue and weakness in the hands and arms
4. Tremors or spasms in the hands and fingers
5. Pale or discolored skin on the fingers and hands
6. Decreased sensation in the fingertips
7. Swelling, redness, or warmth in the hands and fingers

If left untreated, HAVS can lead to more severe symptoms, including:

1. Permanent nerve damage
2. Loss of dexterity and grip strength
3. Decreased sensation in the fingertips
4. Finger ulcers and amputations
5. Carpal tunnel syndrome
6. Other neurological disorders

There is no cure for HAVS, but it can be managed with a combination of medical treatment and lifestyle changes. Treatment options may include:

1. Medications to relieve symptoms such as pain and inflammation
2. Physical therapy to improve dexterity and grip strength
3. Lifestyle modifications such as avoiding cold temperatures and taking regular breaks to warm up hands
4. Assistive devices such as gloves, splints, or hand braces
5. Surgery in severe cases to relieve compression on nerves or repair damaged tissue.

Prevention is the best course of action for HAVS, and it involves taking steps to reduce exposure to cold temperatures and other risk factors. Some ways to prevent HAVS include:

1. Using proper protective gear such as gloves, hats, and scarves in cold environments
2. Avoiding prolonged exposure to cold temperatures
3. Taking regular breaks to warm up hands and fingers
4. Exercising regularly to improve circulation and reduce risk factors such as smoking and obesity
5. Maintaining a healthy diet and getting enough sleep.

There are several risk factors for developing venous insufficiency, including:

* Age: As we age, our veins become less effective at pumping blood back to the heart, making us more susceptible to venous insufficiency.
* Gender: Women are more likely to develop venous insufficiency than men due to hormonal changes and other factors.
* Family history: If you have a family history of venous insufficiency, you may be more likely to develop the condition.
* Injury or trauma: Injuries or traumas to the veins can damage valves or cause blood clots, leading to venous insufficiency.
* Obesity: Excess weight can put extra pressure on the veins, increasing the risk of venous insufficiency.

Symptoms of venous insufficiency may include:

* Pain, aching, or cramping in the legs
* Swelling, edema, or water retention in the legs
* Skin discoloration or thickening of the skin on the legs
* Itching or burning sensations on the skin
* Ulcers or sores on the skin

If left untreated, venous insufficiency can lead to more serious complications such as:

* Chronic wounds or ulcers
* Blood clots or deep vein thrombosis (DVT)
* Increased risk of infection
* Decreased mobility and quality of life

To diagnose venous insufficiency, a healthcare provider may perform one or more of the following tests:

* Physical examination: A healthcare provider will typically examine the legs and ankles to check for swelling, discoloration, and other symptoms.
* Duplex ultrasound: This non-invasive test uses sound waves to evaluate blood flow in the veins and can detect blockages or other problems.
* Venography: This test involves injecting a dye into the vein to visualize the veins and check for any blockages or abnormalities.
* Imaging tests: Such as MRI, CT scan, or X-rays may be used to rule out other conditions that may cause similar symptoms.

Treatment options for venous insufficiency depend on the underlying cause and severity of the condition, but may include one or more of the following:

* Compression stockings: These specialized stockings provide gentle pressure to the legs and ankles to help improve blood flow and reduce swelling.
* Lifestyle changes: Maintaining a healthy weight, exercising regularly, and avoiding prolonged standing or sitting can help improve symptoms.
* Medications: Such as diuretics, anticoagulants, or pain relievers may be prescribed to manage symptoms and prevent complications.
* Endovenous laser therapy: This minimally invasive procedure uses a laser to heat and seal off the damaged vein, redirecting blood flow to healthier veins.
* Sclerotherapy: This involves injecting a solution into the affected vein to cause it to collapse and be absorbed by the body.
* Vein stripping: In this surgical procedure, the affected vein is removed through small incisions.

It's important to note that these treatments are usually recommended for more severe cases of venous insufficiency, and for those who have not responded well to other forms of treatment. Your healthcare provider will help determine the best course of treatment for your specific case.

The exact cause of postphlebitic syndrome is not known, but it is thought to be due to inflammation and scarring in the vein wall after a DVT has resolved. The condition can develop months or even years after the initial DVT and can affect one or both legs.

Symptoms of postphlebitic syndrome may include:

1. Chronic pain or tenderness in the affected limb
2. Swelling, redness, and warmth in the affected limb
3. Skin discoloration (hypo-pigmentation) or hyper-pigmentation in the affected limb
4. Limited mobility or stiffness in the affected limb
5. Fatigue
6. Night cramps
7. Muscle weakness
8. Raynaud's phenomenon (abnormal blood flow to the fingers and toes)

Postphlebitic syndrome can be difficult to diagnose, as the symptoms can be similar to other conditions such as chronic venous insufficiency or peripheral artery disease. A healthcare provider will typically perform a physical examination and order imaging tests such as ultrasound or venography to confirm the diagnosis.

Treatment for postphlebitic syndrome is focused on relieving symptoms and improving quality of life. This may include:

1. Pain management with medication or compression stockings
2. Elevating the affected limb to reduce swelling
3. Compression stockings to improve blood flow
4. Physical therapy to improve mobility and strength
5. Wound care if there are any open sores
6. Anticoagulation therapy to prevent future DVTs

Early diagnosis and treatment of postphlebitic syndrome can help improve symptoms and quality of life for individuals affected by the condition.

There are two main types of thrombophlebitis:

1. Superficial thrombophlebitis: This type of thrombophlebitis affects the superficial veins, which are located just under the skin. It is often caused by injury or trauma to the vein, and it can cause redness, swelling, and pain in the affected area.
2. Deep vein thrombophlebitis: This type of thrombophlebitis affects the deep veins, which are located deeper in the body. It is often caused by blood clots that form in the legs or arms, and it can cause symptoms such as pain, swelling, and warmth in the affected limb.

Thrombophlebitis can be caused by a variety of factors, including:

1. Injury or trauma to the vein
2. Blood clotting disorders
3. Prolonged bed rest or immobility
4. Surgery or medical procedures
5. Certain medications, such as hormone replacement therapy or chemotherapy
6. Age, as the risk of developing thrombophlebitis increases with age
7. Family history of blood clotting disorders
8. Increased pressure on the veins, such as during pregnancy or obesity

Thrombophlebitis can be diagnosed through a variety of tests, including:

1. Ultrasound: This test uses sound waves to create images of the veins and can help identify blood clots or inflammation.
2. Venography: This test involves injecting a dye into the vein to make it visible under X-ray imaging.
3. Blood tests: These can be used to check for signs of blood clotting disorders or other underlying conditions that may be contributing to the development of thrombophlebitis.

Treatment for thrombophlebitis typically involves anticoagulation therapy, which is designed to prevent the blood clot from growing larger and to prevent new clots from forming. This can involve medications such as heparin or warfarin, or other drugs that work by blocking the production of clots. In some cases, a filter may be placed in the vena cava, the large vein that carries blood from the lower body to the heart, to prevent clots from traveling to the lungs.

In addition to anticoagulation therapy, treatment for thrombophlebitis may also include:

1. Elevation of the affected limb to reduce swelling
2. Compression stockings to help reduce swelling and improve blood flow
3. Pain management with medication or heat or cold applications
4. Antibiotics if there is an infection
5. Rest and avoiding strenuous activities until the symptoms resolve.

In some cases, surgery may be necessary to remove the clot or repair the affected vein.

It's important to note that early diagnosis and treatment of thrombophlebitis can help prevent complications such as infection, inflammation, or damage to the valves in the affected vein. If you suspect you or someone else may have thrombophlebitis, it is important to seek medical attention promptly.

There are several possible causes of airway obstruction, including:

1. Asthma: Inflammation of the airways can cause them to narrow and become obstructed.
2. Chronic obstructive pulmonary disease (COPD): This is a progressive condition that damages the lungs and can lead to airway obstruction.
3. Bronchitis: Inflammation of the bronchial tubes (the airways that lead to the lungs) can cause them to narrow and become obstructed.
4. Pneumonia: Infection of the lungs can cause inflammation and narrowing of the airways.
5. Tumors: Cancerous tumors in the chest or throat can grow and block the airways.
6. Foreign objects: Objects such as food or toys can become lodged in the airways and cause obstruction.
7. Anaphylaxis: A severe allergic reaction can cause swelling of the airways and obstruct breathing.
8. Other conditions such as sleep apnea, cystic fibrosis, and vocal cord paralysis can also cause airway obstruction.

Symptoms of airway obstruction may include:

1. Difficulty breathing
2. Wheezing or stridor (a high-pitched sound when breathing in)
3. Chest tightness or pain
4. Coughing up mucus or phlegm
5. Shortness of breath
6. Blue lips or fingernail beds (in severe cases)

Treatment of airway obstruction depends on the underlying cause and may include medications such as bronchodilators, inhalers, and steroids, as well as surgery to remove blockages or repair damaged tissue. In severe cases, a tracheostomy (a tube inserted into the windpipe to help with breathing) may be necessary.

There are several types of apnea that can occur during sleep, including:

1. Obstructive sleep apnea (OSA): This is the most common type of apnea and occurs when the airway is physically blocked by the tongue or other soft tissue in the throat, causing breathing to stop for short periods.
2. Central sleep apnea (CSA): This type of apnea occurs when the brain fails to send the proper signals to the muscles that control breathing, resulting in a pause in breathing.
3. Mixed sleep apnea (MSA): This type of apnea is a combination of OSA and CSA, where both central and obstructive factors contribute to the pauses in breathing.
4. Hypopneic apnea: This type of apnea is characterized by a decrease in breathing, but not a complete stop.
5. Hypercapnic apnea: This type of apnea is caused by an excessive buildup of carbon dioxide in the blood, which can lead to pauses in breathing.

The symptoms of apnea can vary depending on the type and severity of the condition, but may include:

* Pauses in breathing during sleep
* Waking up with a dry mouth or sore throat
* Morning headaches
* Difficulty concentrating or feeling tired during the day
* High blood pressure
* Heart disease

Treatment options for apnea depend on the underlying cause, but may include:

* Lifestyle changes, such as losing weight, avoiding alcohol and sedatives before bedtime, and sleeping on your side
* Oral appliances or devices that advance the position of the lower jaw and tongue
* Continuous positive airway pressure (CPAP) therapy, which involves wearing a mask during sleep to deliver a constant flow of air pressure into the airways
* Bi-level positive airway pressure (BiPAP) therapy, which involves two levels of air pressure: one for inhalation and another for exhalation
* Surgery to remove excess tissue in the throat or correct physical abnormalities that are contributing to the apnea.

Hypercapnia is a medical condition where there is an excessive amount of carbon dioxide (CO2) in the bloodstream. This can occur due to various reasons such as:

1. Respiratory failure: When the lungs are unable to remove enough CO2 from the body, leading to an accumulation of CO2 in the bloodstream.
2. Lung disease: Certain lung diseases such as chronic obstructive pulmonary disease (COPD) or pneumonia can cause hypercapnia by reducing the ability of the lungs to exchange gases.
3. Medication use: Certain medications, such as anesthetics and sedatives, can slow down breathing and lead to hypercapnia.

The symptoms of hypercapnia can vary depending on the severity of the condition, but may include:

1. Headaches
2. Dizziness
3. Confusion
4. Shortness of breath
5. Fatigue
6. Sleep disturbances

If left untreated, hypercapnia can lead to more severe complications such as:

1. Respiratory acidosis: When the body produces too much acid, leading to a drop in blood pH.
2. Cardiac arrhythmias: Abnormal heart rhythms can occur due to the increased CO2 levels in the bloodstream.
3. Seizures: In severe cases of hypercapnia, seizures can occur due to the changes in brain chemistry caused by the excessive CO2.

Treatment for hypercapnia typically involves addressing the underlying cause and managing symptoms through respiratory support and other therapies as needed. This may include:

1. Oxygen therapy: Administering oxygen through a mask or nasal tubes to help increase oxygen levels in the bloodstream and reduce CO2 levels.
2. Ventilation assistance: Using a machine to assist with breathing, such as a ventilator, to help remove excess CO2 from the lungs.
3. Carbon dioxide removal: Using a device to remove CO2 from the bloodstream, such as a dialysis machine.
4. Medication management: Adjusting medications that may be contributing to hypercapnia, such as anesthetics or sedatives.
5. Respiratory therapy: Providing breathing exercises and other techniques to help improve lung function and reduce symptoms.

It is important to seek medical attention if you suspect you or someone else may have hypercapnia, as early diagnosis and treatment can help prevent complications and improve outcomes.

The exact cause of Raynaud disease is not fully understood, but it is believed to be related to an autoimmune disorder, in which the body's immune system mistakenly attacks healthy tissue. The condition can occur on its own or as a secondary symptom of another underlying medical condition such as scleroderma or rheumatoid arthritis.

Symptoms of Raynaud Disease:

1) Discoloration: Raynaud disease causes the affected areas to turn white or blue in response to cold temperatures or stress.

2) Pain: The constriction of blood vessels can cause pain in the affected areas.

3) Numbness or tingling: The lack of blood flow can cause numbness or tingling sensations in the fingers and toes.

4) Swelling: In severe cases, swelling may occur in the affected areas.

5) Burning sensation: Some people with Raynaud disease may experience a burning sensation in their hands and feet.

Diagnosis of Raynaud Disease:

1) Medical history: A doctor will ask about symptoms, medical history, and any triggers that may cause the condition.

2) Physical examination: The doctor will perform a physical examination to look for signs of discoloration or swelling in the affected areas.

3) Tests: Additional tests such as nailfold capillary microscopy, pulse volume recording and thermography may be ordered to confirm the diagnosis.

Treatment options for Raynaud Disease:

1) Medications: Drugs such as calcium channel blockers, alpha-blockers, and anticoagulants can help to relax blood vessels and improve blood flow.

2) Lifestyle changes: Avoiding triggers such as cold temperatures and taking steps to keep hands and feet warm can help manage the condition.

3) Alternative therapies: Some people with Raynaud disease may find relief with alternative therapies such as acupuncture or biofeedback.

It is important to note that in some cases, Raynaud disease can be a symptom of an underlying autoimmune disorder, such as lupus or scleroderma. If you suspect you have Raynaud disease, it is essential to seek medical attention to rule out any other conditions.

The symptoms of a varicose ulcer may include:

* Pain and tenderness in the affected leg
* Swelling and redness around the wound site
* Discharge of fluid or pus from the wound
* Foul odor emanating from the wound
* Skin that is warm to touch

The risk factors for developing a varicose ulcer include:

* Age, as the risk increases with age
* Gender, as women are more likely to develop them than men
* Family history of varicose veins or other circulatory problems
* Obesity
* Pregnancy and childbirth
* Prolonged standing or sitting
* Previous history of deep vein thrombosis (DVT) or pulmonary embolism (PE)

Treatment for varicose ulcers typically involves a combination of wound care, compression therapy, and addressing the underlying cause of the ulcer. This may include:

* Cleaning and dressing the wound to promote healing and prevent infection
* Applying compression stockings or bandages to reduce swelling and improve blood flow
* Elevating the affected limb to reduce swelling
* Taking antibiotics to treat any underlying infections
* Using sclerotherapy to close off the ruptured vein
* In some cases, surgery may be necessary to repair or remove the affected vein.

It is important for individuals with varicose ulcers to seek medical attention if they experience any signs of infection, such as increased pain, swelling, redness, or pus, as these wounds can lead to serious complications if left untreated.

There are different types of anoxia, including:

1. Cerebral anoxia: This occurs when the brain does not receive enough oxygen, leading to cognitive impairment, confusion, and loss of consciousness.
2. Pulmonary anoxia: This occurs when the lungs do not receive enough oxygen, leading to shortness of breath, coughing, and chest pain.
3. Cardiac anoxia: This occurs when the heart does not receive enough oxygen, leading to cardiac arrest and potentially death.
4. Global anoxia: This is a complete lack of oxygen to the entire body, leading to widespread tissue damage and death.

Treatment for anoxia depends on the underlying cause and the severity of the condition. In some cases, hospitalization may be necessary to provide oxygen therapy, pain management, and other supportive care. In severe cases, anoxia can lead to long-term disability or death.

Prevention of anoxia is important, and this includes managing underlying medical conditions such as heart disease, diabetes, and respiratory problems. It also involves avoiding activities that can lead to oxygen deprivation, such as scuba diving or high-altitude climbing, without proper training and equipment.

In summary, anoxia is a serious medical condition that occurs when there is a lack of oxygen in the body or specific tissues or organs. It can cause cell death and tissue damage, leading to serious health complications and even death if left untreated. Early diagnosis and treatment are crucial to prevent long-term disability or death.

There are two types of hypertension:

1. Primary Hypertension: This type of hypertension has no identifiable cause and is also known as essential hypertension. It accounts for about 90% of all cases of hypertension.
2. Secondary Hypertension: This type of hypertension is caused by an underlying medical condition or medication. It accounts for about 10% of all cases of hypertension.

Some common causes of secondary hypertension include:

* Kidney disease
* Adrenal gland disorders
* Hormonal imbalances
* Certain medications
* Sleep apnea
* Cocaine use

There are also several risk factors for hypertension, including:

* Age (the risk increases with age)
* Family history of hypertension
* Obesity
* Lack of exercise
* High sodium intake
* Low potassium intake
* Stress

Hypertension is often asymptomatic, and it can cause damage to the blood vessels and organs over time. Some potential complications of hypertension include:

* Heart disease (e.g., heart attacks, heart failure)
* Stroke
* Kidney disease (e.g., chronic kidney disease, end-stage renal disease)
* Vision loss (e.g., retinopathy)
* Peripheral artery disease

Hypertension is typically diagnosed through blood pressure readings taken over a period of time. Treatment for hypertension may include lifestyle changes (e.g., diet, exercise, stress management), medications, or a combination of both. The goal of treatment is to reduce the risk of complications and improve quality of life.

The diagnosis of BHR is based on a combination of clinical, physiological, and imaging tests. The most common method used to assess BHR is the methacholine or histamine challenge test, which involves inhaling progressively increasing concentrations of these substances to measure airway reactivity. Other tests include exercise testing, hyperventilation, and mannitol challenge.

BHR is characterized by an increased responsiveness of the airways to various stimuli, such as allergens, cold or exercise, leading to inflammation and bronchoconstriction. This can cause symptoms such as wheezing, coughing, shortness of breath, and chest tightness.

There are several risk factors for BHR, including:

* Allergies
* Respiratory infections
* Exposure to environmental pollutants
* Genetic predisposition
* Obesity
* Smoking

Treatment of BHR typically involves the use of bronchodilators, corticosteroids, and other medications to reduce inflammation and airway constriction. In severe cases, surgical procedures such as lung volume reduction or bronchial thermoplasty may be necessary. Environmental modifications, such as avoiding triggers and using HEPA filters, can also help manage symptoms.

In summary, bronchial hyperreactivity is a condition characterized by an exaggerated response of the airways to various stimuli, leading to increased smooth muscle contraction and narrowing of the bronchi. It is commonly seen in asthma and other respiratory diseases, and can cause symptoms such as wheezing, coughing, shortness of breath, and chest tightness. Treatment typically involves medications and environmental modifications to reduce inflammation and airway constriction.

Symptoms of venous thrombosis may include pain, swelling, warmth, and redness in the affected limb. In some cases, the clot can break loose and travel to the lungs, causing a potentially life-threatening condition called Pulmonary Embolism (PE).

Treatment for venous thrombosis typically involves anticoagulant medications to prevent the clot from growing and to prevent new clots from forming. In some cases, a filter may be placed in the vena cava, the large vein that carries blood from the lower body to the heart, to prevent clots from traveling to the lungs.

Prevention of venous thrombosis includes encouraging movement and exercise, avoiding long periods of immobility, and wearing compression stockings or sleeves to compress the veins and improve blood flow.

Symptoms of hypovolemia may include:

* Decreased blood pressure
* Tachycardia (rapid heart rate)
* Tachypnea (rapid breathing)
* Confusion or disorientation
* Pale, cool, or clammy skin
* Weakness or fatigue

Treatment of hypovolemia typically involves fluid resuscitation, which may involve the administration of intravenous fluids, blood transfusions, or other appropriate interventions to restore blood volume and pressure. In severe cases, hypovolemia can lead to sepsis, organ failure, and death if left untreated.

It is important for medical professionals to quickly identify and treat hypovolemia in order to prevent complications and improve patient outcomes.

... can be used also in supine and prone positions. Optoelectronic plethysmography was used to study ... From optoelectronic plethysmography it is thus possible to obtain volume variations of the entire chest wall and its different ... Optoelectronic plethysmography is a method to evaluate ventilation through an external measurement of the chest wall surface ... Optoelectronic plethysmography can be used following different measurement protocols, specifically developed for different ...
... the argument for penile plethysmography being a more reliable gauge of sexual arousal than vaginal plethysmography is still ... In fact, penile plethysmography has received a mixed reception in Quebec courts: Protection de la jeunesse - 539, [1992] R.J.Q ... Penile plethysmography (PPG) or phallometry is measurement of blood flow to the penis, typically used as a proxy for ... One such criticism is that while penile plethysmography is said to be important for being more objective than a test subject's ...
... (ADP, also known as whole-body air displacement plethysmography) is a recognized and ... Air-displacement plethysmography offers several advantages over established reference methods, including a quick, comfortable, ... The principles of plethysmography were first applied to the measurement of the body volume and composition of infants in the ... "Body-composition assessment via air-displacement plethysmography in adults and children: a review". The American Journal of ...
... (SLP) technology is a noninvasive method for collecting accurate representations of chest and ... ATS 2010 Am J Respir Crit Care Med 181;2010:A2170 7. Tidal breathing parameters measured by structured light plethysmography ( ... 4(3): 159-166 (1986) 5. Structured light Plethysmography in infants and Children - a pilot study. Juliet Usher-Smith, Richard ... BTS 2009 Thorax 2009;64:A51-A54 5. Comparison of Tidal Breathing with Structured Light Plethysmography (SLP) and Spirometry ...
... (RIP) is a method of evaluating pulmonary ventilation by measuring the movement of the ... RIP is the most frequently used, established and accurate plethysmography method to estimate lung volume from respiratory ... Dual band respiratory inductance plethysmography can be used to describe various measures of complex respiratory patterns. The ... Dual band respiratory inductance plethysmography was validated in determining tidal volume during exercise and shown to be ...
Air plethysmography and the effect of elastic compression on the venous haemodynamics of the leg. J Vasc Surg 1987;5:148-159. ... Air plethysmography. in: Raju S, Villavicencio JL., Surgical management of venous disease. Cidade: Willians & Wilkins; 1997:93 ... Combining segmental systolic pressure and plethysmography to diagnose arterial occlusive disease of the legs. Am J Surg 1979; ...
Impedance Plethysmography". www.bem.fi. Kubicek W.G., Witsoe, D.A., Patterson, R.P., Mosharrata, M.A., Karnegis, J.N., From, A. ... Impedance cardiography (ICG), also referred to as electrical impedance plethysmography (EIP) or Thoracic Electrical ...
Shelley K, Shelley S, Lake C (2001). "Pulse Oximeter Waveform: Photoelectric Plethysmography". In Lake C, Hines R, Blitt C (eds ... The results are comparable to blood pulse monitored by plethysmography during an occlusion-reperfusion experiment. A major ...
Three tests were conducted using penile plethysmography. While there was no difference in response when the men were exposed to ...
Jacquemin, C; Varène P (December 1968). "Paul Bert and body plethysmography (1868-1968)". La Presse Médicale. 76 (50): 2403-4. ...
"Body plethysmography - Its principles and clinical use". Respiratory Medicine. 105 (7): 959-971. doi:10.1016/j.rmed.2011.02.006 ...
... can be measured using plethysmography. Analogously to Ohm's Law: R A W = Δ P V ˙ {\displaystyle R_{AW}={\frac ...
G.E. Burch, Digital Plethysmography, Grune and Sratton publ, 1954. G.E. Burch, Of Publishing Scientific Papers, Grune and ... 1946 Award from the Mexican National Assembly of Surgeons for Distinguished Science, on plethysmography 1947 Gold Medal Award ...
Other complementary lung functions tests include plethysmography and nitrogen washout. The most common parameters measured in ...
The impedance plethysmography allows determining changes in volume of the body tissues based on the measurement of the electric ... "Estimation of Cardiac Output by using surface electrodes for measuring the impedance plethysmography" (PDF). Navat. Gabarrón, ... "Non-invasive Cardiac Output measurement by impedance plethysmography under general anaesthesia". Eur. Soc. Anaesthesiol.: 4-6. ...
... the utility of spirometry and plethysmography". Chest. American College of Chest Physicians. 122 (6): 2246-9. doi:10.1378/chest ...
Distal plethysmography also yields useful information about circulatory status in digits. To rule out other forms of vasculitis ...
"Accuracy of Consumer Grade Bioelectrical Impedance Analysis Devices Compared to Air Displacement Plethysmography". Int J Exerc ...
Murphy AJ, Buntain HM, Wong JC, Greer RM, Wainwright CE, Davies PS (July 2004). "The Use of Air Displacement Plethysmography in ...
Lung volume measurements taken with cabinless plethysmography are considered equivalent to body plethysmography. Boyle's Law is ... Optoelectronic plethysmography Photoplethysmograph Respiratory inductance plethysmography πληθυσμός, γράφειν. Liddell, Henry ... In water plethysmography an extremity, e.g. an arm, is enclosed in a water-filled chamber where volume changes can be detected ... Air plethysmography uses a similar principle but based on an air-filled long cuff, which is more convenient but less accurate. ...
Air-displacement plethysmography offers several advantages over established reference methods, including a quick, comfortable, ... Fields DA, Goran MI, McCrory MA (March 2002). "Body-composition assessment via air-displacement plethysmography in adults and ... Whole-body air displacement plethysmography (ADP) is a recognised and scientifically validated densitometric method to measure ... Lowry DW, Tomiyama AJ (January 21, 2015). "Air displacement plethysmography versus dual-energy x-ray absorptiometry in ...
This measurement of blood flow to the male genitals is known as penile plethysmography. This is commonly measured using a ...
"Air-Plethysmography and the effect of elastic compression on venous hemodynamics of the leg.", Journal of Vascular Surgery, ...
Christopoulos DG, Nicolaides AN, Szendro G, Irvine AT, Bull ML, Eastcott HH (January 1987). "Air-plethysmography and the effect ...
"Measurement of chest wall volume changes by optoelectronic plethysmography (OEP) in newborns during CPAP". re.public.polimi.it ...
Diagnoses were commonly performed by impedance plethysmography in the 1970s and 1980s, but ultrasound, particularly after ... Yet, in the mid-1990s, contrast venography and impedance plethysmography were still described as common. Multiple ...
"Changes in sexual arousal as measured by penile plethysmography in men with pedophilic sexual interest". Journal of Sexual ... found that treatment has been effective in changing sexual arousal towards children as measured by the penile plethysmography ...
The movement of the belts is typically measured with piezoelectric sensors or respiratory inductance plethysmography. This ...
"Changes in Sexual Arousal as Measured by Penile Plethysmography in Men with Pedophilic Sexual Interest". J Sex Med. 11: 1221-9 ...
The technique uses air as opposed to water and is known as air displacement plethysmography (ADP). Subjects enter a sealed ...
Limb plethysmography is a test that compares blood pressure in the legs and arms. ... Plethysmography may be done for very ill people who cannot travel to the arteriography lab. This test can be used to screen for ... Limb plethysmography is a test that compares blood pressure in the legs and arms. ...
The generalized stress inherent to head-out plethysmography testing exacerbated the respiratory effects of DSM421 and was ... Care should be taken when choosing whether to use head-out versus whole-body plethysmography chambers during respiratory ... Increased stress associated with head-out plethysmography testing can exacerbate respiratory effects and lead to mortality in ... Respiratory changes and toxicity (resulting in euthanasia in extremis) were confirmed in a repeat, head-out plethysmography ...
Heroin- and Fentanyl-Induced Respiratory Depression in a Rat Plethysmography Model: Potency, Tolerance, and Sex Differences ... Heroin- and Fentanyl-Induced Respiratory Depression in a Rat Plethysmography Model: Potency, Tolerance, and Sex Differences ... We used whole-body plethysmography to first establish dose-response curves by recording breathing for 60 minutes post- ...
Optoelectronic plethysmography (OEP) is a 3D motion capture technique that provides a comprehensive noninvasive assessment of ... Breathing Pattern Disorders Distinguished from Healthy Breathing Patterns Using Oxptoelectronic Plethysmography. Translational ...
DSI FinePointe Software with Buxco Unrestrained Plethysmography Chambers. *Assess Breathing Parameters *Breathing Rate ...
Body plethysmography. Body plethysmography may be used to measure: *Total lung capacity (TLC). This is the total amount of air ... If you have body plethysmography, you will be asked to sit inside a small enclosure. It's like a phone booth, with windows ... If you have body plethysmography, you may feel uncomfortable in the airtight booth. But the therapist will be nearby to open ...
Whole body plethysmography. Intra-thoracic gas volume was measured near functional residual capacity with a barometric whole ... Subjects underwent whole body plethysmography, followed by four measurements of TL,CO,sb. Two measurements were taken with a ... ratio measured with plethysmography. ═: 95% confidence interval. Regression line: TL,CO,sb at 17.5% FI,O2/21% FI,O2 (%)=−0.006× ... ratio measured with plethysmography. The lines show regression and 95% confidence intervals for 21% inspired oxygen fraction (F ...
Plethysmography is the measurement of variations in the size of an organ or body part on the basis of the amount of blood ... Hemodynamic Changes in the Small Vessels in Man as Analyzed by Digital Plethysmography. Contributor(s):. Johnson, Robert L.. ...
Start Over You searched for: Subjects Plethysmography -- instrumentation ✖Remove constraint Subjects: Plethysmography -- ... Plethysmography -- instrumentation. Blood Pressure Monitors. Blood Pressure -- physiology. Heart Rate -- physiology. Monitoring ...
Agreement and validity between body fat estimated by skinfold measurement and air displacement plethysmography in adolescents ... validity between relative body fat percentages estimated using anthropometric measurements and air displacement plethysmography ...
Evaluation of state of circulation in radiation injury using impedance plethysmography.. Authors: Iyer, G K. Jindal, G D. ... Evaluation of state of circulation in radiation injury using impedance plethysmography. Journal of Postgraduate Medicine. 1990 ...
Thoracic Gas Volume Measured by Body Plethysmography during Anesthesia and Muscle Paralysis: °Description and Validation of a ... Göran Hedenstierna, Per-Olof Järnberg, Ingeborg Gottlieb; Thoracic Gas Volume Measured by Body Plethysmography during ...
Evaluation of Respiratory Inductive Plethysmography Using the EMKAbelt System in the Conscious Dog and Primate. ...
To evaluate the reliability of the Nellcor N200 pulse oximeter in the detection of hyperoxemia (oxygen tension | 80 mm Hg), we obtained 213 simultaneous recordings and measurements of transcutaneous oxygen saturation (SO2) and arterial oxygen tension (PaO2) in 50 patients. During 95% of measureme …
by Keyword: Plethysmography. Jané, R., Lazaro, J., Ruiz, P., Gil, E., Navajas, D., Farre, R., Laguna, P., (2013). Obstructive ... Plethysmography, Pneumodynamics, Sensitivity analysis, Sleep, Spectral analysis, Cheyne-Stokes respiration, Climbing periods, ... Respiratory inductive plethysmography, Respiratory pattern, Respiratory volume signal, Sleep apnea, Spectral analysis, Spectral ... derived from respiratory inductive plethysmography and evaluated through a linear discriminant analysis. A dataset of 34 ...
Novel whole body plethysmography system for the continuous characterization of sleep and breathing in a mouse. ... Dive into the research topics of Novel whole body plethysmography system for the continuous characterization of sleep and ...
air displacement plethysmography (Bod Pod). *bioimpedance spectroscopy (BIS). *3-D body scanners ...
Method 1(Default): Body Plethysmography-performed in a closed transparent cabin. Body plethysmography is considered the gold ... Impulse ocillometry complements conventional tests such as spirometry, body plethysmography, and lung diffusion. Impulse ...
Impedance plethysmography: basic principles.. JP Babu, GD Jindal, AC Bhuta, GB Parulkar. April-June 1990, 36(2):57-63. PMID: ... Technical aspects of impedance plethysmography.. AC Bhuta, JP Babu, GD Jindal, GB Parulkar. April-June 1990, 36(2):64-70. PMID: ... Impedance Plethysmography technique has been discussed with explanation of two compartment model and parallel conductor theory ... Diagnosis of aortic occlusive diseases using impedance plethysmography.. AK Deshpande, GD Jindal, IP Babu, SN Nerurkar, MD ...
BBF was measured by the method of impedance plethysmography. The first was a pilot study in which BBF in 14 men was studied ...
... electronic plethysmography; antenna radiation pattern measurements; stereovector- electrocardiography; phase space displays; ...
Speckle Plethysmography Pulse Transit Time as a Marker of Blood Pressure Changes. This study is currently recruiting ... To test a new technique (speckle plethysmography) for measuring blood pressure in healthy adults. ...
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  • IMSEAR at SEARO: Evaluation of state of circulation in radiation injury using impedance plethysmography. (who.int)
  • Technical aspects of impedance plethysmography. (jpgmonline.com)
  • BBF was measured by the method of impedance plethysmography. (epa.gov)
  • 3. Reevaluation of the sensitivity of impedance plethysmography for the detection of proximal deep vein thrombosis. (nih.gov)
  • 4. Limitations of impedance plethysmography in the diagnosis of clinically suspected deep-vein thrombosis. (nih.gov)
  • 5. Comparison of the accuracy of impedance plethysmography and compression ultrasonography in outpatients with clinically suspected deep vein thrombosis. (nih.gov)
  • 7. Features of thrombi and diagnostic accuracy of impedance plethysmography in symptomatic and asymptomatic deep vein thrombosis. (nih.gov)
  • 9. An evaluation of impedance plethysmography and 125I-fibrinogen leg scanning in patients following hip surgery. (nih.gov)
  • 13. Early diagnosis of deep vein thrombosis following total hip replacement using impedance plethysmography: advantages and limitations of this approach. (nih.gov)
  • 14. The limitations of impedance plethysmography in the diagnosis of acute deep venous thrombosis. (nih.gov)
  • 15. Deep vein thrombosis following aortic surgery: prospective evaluation of I125 fibrinogen and impedance plethysmography. (nih.gov)
  • 16. Occlusive impedance plethysmography. (nih.gov)
  • A comparison of venography, impedance plethysmography, and radiolabeled fibrinogen. (nih.gov)
  • Care should be taken when choosing whether to use head-out versus whole-body plethysmography chambers during respiratory function testing in animals. (sri.com)
  • Assess the agreement and validity between relative body fat percentages estimated using anthropometric measurements and air displacement plethysmography ( ADP ). (bvsalud.org)
  • Neonatal body composition was measured using air displacement plethysmography. (nih.gov)
  • and (3) low neonatal body fat percentage (BF%, measured by air displacement plethysmography) reflecting reduced nutritional reserve in utero. (biomedcentral.com)
  • Plethysmography is the measurement of variations in the size of an organ or body part on the basis of the amount of blood passing through or present in the part. (nih.gov)
  • Body plethysmography is considered the gold standard of lung volume measurement. (nih.gov)
  • Lung function was assessed by a combination of whole-body barometric plethysmography, invasive measurement of airway resistance, and isometric force measurements in isolated bronchial rings. (nih.gov)
  • When tested in a core battery of safety pharmacology assays, DSM421 did not produce any effects at oral doses up to 750 mg/kg in an Irwin test in rats, but a respiratory study in rats using head-out plethysmography resulted in substantial changes in respiratory function as well as moribundity and mortality at that and lower doses. (sri.com)
  • Respiratory changes and toxicity (resulting in euthanasia in extremis) were confirmed in a repeat, head-out plethysmography test, but the effects of DSM421 were much less severe overall when the rats were tested in whole-body chambers. (sri.com)
  • The generalized stress inherent to head-out plethysmography testing exacerbated the respiratory effects of DSM421 and was possibly compounded by DSM421's cardiovascular effects, thus artifactually resulting in moribundity and mortality in rats. (sri.com)
  • A number of spectral parameters are extracted from the power spectral density (PSD) of the volume signal, derived from respiratory inductive plethysmography and evaluated through a linear discriminant analysis. (ibecbarcelona.eu)
  • Plethysmography equipment: real time respiratory inductive plethysmography (RIP) technology, algorithm based (Ponemah, Buxco, SmartLab platforms-DSI Inc., Hans Rudolph Inc. (nih.gov)
  • Potential testing errors, differences in types of plethysmography testing chambers, effects on stress indicators, and off-target activity were investigated. (sri.com)
  • Lung function outcomes were measured by spirometry, plethysmography, and oscillometry. (cdc.gov)
  • The ratio of T L,CO,sb measurements was strictly independent of the residual volume/total lung capacity ratio measured with plethysmography. (ersjournals.com)
  • Body plethysmography. (cigna.com)
  • Body Plethysmography-performed in a closed transparent cabin. (nih.gov)
  • Limb plethysmography is a test that compares blood pressure in the legs and arms. (medlineplus.gov)
  • To test a new technique (speckle plethysmography) for measuring blood pressure in healthy adults. (nih.gov)
  • Estimation of sleep stages in a healthy adult population from optical plethysmography and accelerometer signals. (ohsu.edu)
  • Optoelectronic plethysmography (OEP) is a 3D motion capture technique that provides a comprehensive noninvasive assessment of chest wall during rest and exercise. (kent.ac.uk)
  • A comparison with plethysmography and phlebography. (nih.gov)
  • To test a new technique (speckle plethysmography) for measuring blood pressure in healthy adults. (nih.gov)
  • The student would analyze data comparing PWV to speckle-plethysmography (SPG) signals (a measure of blood flow) from a wearable device. (nih.gov)
  • Patients with chronic persistent asthma may have hyperinflation, as evidenced by an increased total lung capacity (TLC) at plethysmography. (medscape.com)
  • Plethysmography measures changes in volume in different parts of the body. (medlineplus.gov)
  • Body Plethysmography-performed in a closed transparent cabin. (nih.gov)