PULMONARY FUNCTIONS DURING SATURATION-EXCURSION DIVES BREATHING AIR
Abstract
Divers work at increased pressures and this results in increased gas densities for a given breathing mixture. The increased density causes an increase in the work of breathing and consequently reduces the maximum ventilation possible during exertion, a condition which sets the limit for useful work at depth. As a part of the general preparatory program for the SEALAB II project, lung function tests were performed on divers during saturation-excursion dives, and also during surface dives ('bottom-drops') in a dry chamber. The saturation-excursion dives consisted of a 24-hour saturation exposure at 35 feet and excursions from this depth to depths varying from 105- 165 feet. Maximal inspiratory and expiratory flow rates are two functions which show a depth-dependent reduction during diving. The findings in these studies indicate that after a 24-hour saturation period at depths, adaptation had taken place which resulted in an improvement in flow rates. The subsequent excursion dives reduced the maximal inspiratory flow rates to a significantly lesser degree than during comparative acute exposures to equivalent depths. It is hoped that the time course of maximal flow rate can be established during prolonged exposure to high pressures in SEALAB III. There would be a high probability that the predicted improvement in flow rates would be associated with a higher level for useful work at depth.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 04, 1968
- Accession Number
- AD0670198
Entities
People
- James H. Dougherty Jr.
- Karl E. Schaefer
Organizations
- Naval Submarine Medical Research Laboratory