Diurnal variation in pulmonary diffusing capacity and expiratory volumes
Panda, A.; McHardy, G.
Indian Journal of Physiology and Pharmacology 24(2): 112-118
1980
ISSN/ISBN: 0019-5499 PMID: 7189745 Document Number: 158141
The pulmonary diffusing capacity for Carbonmonoxide (DLCO) was measured in 20 normal volunteers of either sex at 9 a.m., 12 noon and 5 p.m. Forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were also determined after each DLCO measurement. There was a fall in the mean noon value of the diffusing capacity of the lungs which was statistically significant. The value at 5 p.m. was almost same as the noon value. The forced expiratory volume in one second and the forced vital capacity followed a similar trend. The DLCO, FEV1 and FVC appear to exhibit a diurnal rhythm.