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A Model to Simulate Clinically Relevant Hypoxia in Humans
Published on: December 22, 2016
Decompression sickness in breath-hold divers: a review.
Frederic Lemaitre1, Andreas Fahlman, Bernard Gardette
1Faculty of Sport Sciences, University of Rouen, Mont-Saint-Aignan, France.
Journal of Sports Sciences
|December 8, 2009
Summary
Repeated breath-hold dives, especially with short surface intervals, can increase nitrogen levels and risk decompression sickness in humans and marine mammals. Deep diving may reduce this risk through physiological adaptations.
Area of Science:
- Physiology
- Marine Biology
- Diving Medicine
Background:
- Decompression sickness (DCS) risk is generally considered low for single breath-hold dives.
- Marine mammals and human divers undertake dives that may elevate nitrogen tension.
- Neurological symptoms and DCS-like conditions have been observed in both humans and marine mammals.
Purpose of the Study:
- To investigate the cumulative effects of repeated breath-hold dives on nitrogen tension.
- To explore the potential risk of decompression sickness in humans and marine mammals.
- To identify factors predisposing to DCS in breath-hold diving.
Main Methods:
- Review of existing literature on breath-hold diving physiology.
- Analysis of dive profiles in marine mammals and human divers.
- Examination of reported neurological symptoms and necropsy findings.
- Modeling of nitrogen accumulation during dives.
Main Results:
- Repeated dives with short surface intervals increase cumulative nitrogen load.
- Diving to significant depths (30-40m or >200m) can lead to DCS symptoms.
- Physiological mechanisms like pulmonary shunts and lung collapse may mitigate DCS risk during deep dives.
Conclusions:
- Repeated breath-hold dives with short surface intervals are a significant risk factor for DCS.
- Marine mammals and human divers may be at risk of DCS, particularly when altering dive patterns.
- Pulmonary and lung mechanisms during deep dives may offer protection against DCS.
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