Search results
Results from the WOW.Com Content Network
Diffusing capacity of the lung (D L) (also known as transfer factor) measures the transfer of gas from air in the lung, to the red blood cells in lung blood vessels. It is part of a comprehensive series of pulmonary function tests to determine the overall ability of the lung to transport gas into and out of the blood.
D LCO or T LCO (diffusing capacity or transfer factor of the lung for carbon monoxide (CO), [1]) is the extent to which oxygen passes from the air sacs of the lungs into the blood. Commonly, it refers to the test used to determine this parameter. It was introduced in 1909. [2]
Pulmonary function testing (PFT) is a complete evaluation of the respiratory system including patient history, physical examinations, and tests of pulmonary function. The primary purpose of pulmonary function testing is to identify the severity of pulmonary impairment. [1]
TLC: Total lung capacity: the volume in the lungs at maximal inflation, the sum of VC and RV. TV: Tidal volume: that volume of air moved into or out of the lungs in 1 breath (TV indicates a subdivision of the lung; when tidal volume is precisely measured, as in gas exchange calculation, the symbol TV or V T is used.)
In obstructive lung disease, the FEV1 is reduced due to an obstruction of air escaping from the lungs. Thus, the FEV1/FVC ratio will be reduced. [4] More specifically, according to the National Institute for Clinical Excellence, the diagnosis of COPD is made when the FEV 1 /FVC ratio is less than 0.7 or [8] the FEV 1 is less than 75% of predicted; [9] however, other authoritative bodies have ...
The rest of the difference is due to the continual uptake of oxygen by the pulmonary capillaries, and the continual diffusion of CO 2 out of the capillaries into the alveoli. The alveolar pO 2 is not routinely measured but is calculated from blood gas measurements by the alveolar gas equation .
(In normal individuals, carbon dioxide is the primary determinant of respiratory drive.) Lung function development is reduced in children who grow up near motorways [5] [6] although this seems at least in part reversible. [7] Air pollution exposure affects FEV 1 in asthmatics, but also affects FVC and FEV 1 in healthy adults even at low ...
In respiratory physiology, the ventilation/perfusion ratio (V/Q ratio) is a ratio used to assess the efficiency and adequacy of the ventilation-perfusion coupling and thus the matching of two variables: V – ventilation – the air that reaches the alveoli; Q – perfusion – the blood that reaches the alveoli via the capillaries