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Mechanisms of reduced pulmonary function after a saturation dive
E Thorsen1, K Segadal, B K Kambestad
1Norwegian Underwater Technology Centre, Lakesvåg.
The European Respiratory Journal
|January 1, 1994
Summary
Saturation diving impacts lung function. Hyperoxia, hyperbaria, and gas microemboli independently contribute to these pulmonary changes, potentially explaining long-term effects in divers.
Area of Science:
- Physiology
- Diving Medicine
- Pulmonary Function
Background:
- Saturation diving is known to cause lasting pulmonary function changes.
- The specific factors contributing to these effects require further investigation.
Purpose of the Study:
- To assess the relative contributions of hyperoxia, hyperbaria, and venous gas microemboli to pulmonary function changes after saturation dives.
- To correlate these exposures with specific pulmonary measurements.
Main Methods:
- Pulmonary function tests (lung volumes, flows, TLCO, closing volume) were performed before and after 17 saturation dives (5-450 msw).
- Cumulative hyperoxic and hyperbaric exposures were recorded.
- Venous gas microemboli load was measured during decompression in 41 divers across three dives.
Main Results:
- Transfer factor of the lungs for carbon monoxide (TLCO) decreased by 8.3% post-dive, correlating with hyperoxic exposure and microemboli load independently.
- Closing volume increased and forced mid-expiratory flow rate decreased, correlating with hyperoxic exposure.
- Total lung capacity increased, correlating with hyperbaric exposure.
Conclusions:
- Hyperoxia, hyperbaria, and venous gas microembolism each contribute to pulmonary function alterations following saturation dives.
- These factors may collectively explain the long-term pulmonary effects observed in divers.
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