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No changes in lung function after a saturation dive to 2.5 MPa with intermittent reduction in Po2 during
E Thorsen1, K Segadal, L E B Stuhr
1Institute of Medicine, University of Bergen, Bergen, Norway. einar.thorsen@helse-bergen.no
European Journal of Applied Physiology
|September 14, 2006
Summary
Modified deep saturation dives using slower decompression and reduced hyperoxic exposure appear to preserve lung function and exercise capacity. This study investigated lung function and aerobic capacity in divers after a 2.5 MPa helium-oxygen dive.
Area of Science:
- Physiology
- Hyperbaric Medicine
- Diving Science
Background:
- Deep saturation diving involves decompression stress and hyperoxia, potentially impairing lung function and aerobic capacity.
- Previous dives have shown reductions in transfer factor for carbon monoxide and maximal aerobic capacity.
Purpose of the Study:
- To assess lung function and exercise capacity before and after a modified helium-oxygen saturation dive.
- To evaluate the impact of reduced decompression rates and intermittent hyperoxic exposure on diver physiology.
Main Methods:
- Eight experienced divers underwent a helium-oxygen saturation dive to 2.5 MPa.
- Lung function and exercise capacity were measured pre- and post-dive.
- Oxygen was administered intermittently during decompression to reduce hyperoxic exposure.
Main Results:
- The incidence of venous gas microemboli was low compared to previous deep dives.
- No significant changes in lung function or angiotensin converting enzyme were observed.
- One diver required treatment for decompression sickness.
Conclusions:
- Modified diving procedures, including slower decompression and reduced hyperoxia, may prevent adverse effects on lung function.
- These findings suggest improved safety protocols for deep saturation diving.
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