Respiratory pattern after wet and dry chamber dives to 0.6 MPa ambient pressure in healthy males

The purpose of this study was to evaluate respiratory effects of wet and dr y hyperbaric chamber dives to 0.6 MPa ambient pressure in healthy males. Th ere were 19 and 22 subjects who participated in two series of dives with a bottom time of 15 min and decompression times of 28 and 17 min, respectivel y. Airways conductance, residual volume, forced vital capacity, forced expi ratory volume in 1 sec, mid expiratory flow at 25, 50 and 75% of FVC, and d iffusion capacity for CO wen measured before the divest after 3 h, and afte r 24 h. Multivariate analysis of covariance revealed no statistically signi ficant effects of time or the interaction between time and dry or wet envir onment on the measured lung function parameters. These findings suggest fir st that even deep air dives may not necessarily affect pulmonary function, and second, that factors related to the particular wet environment do not s eem to contribute to lung function changes after dives. (C) 1999 Elsevier S cience B.V. All rights reserved.