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Training Rats to Voluntarily Dive Underwater: Investigations of the Mammalian Diving Response
Published on: November 12, 2014
Preventive effect of pre-dive hydration on bubble formation in divers
E Gempp1, J E Blatteau, J-M Pontier
1Institute of Naval Medicine, BP 610, 83800 Toulon Armées, France. gempp@voila.fr
British Journal of Sports Medicine
|March 1, 2008
Summary
Pre-dive hydration significantly reduces decompression bubbles in divers by improving plasma volume and mitigating dehydration. This simple intervention enhances diving safety and reduces the risk of decompression sickness.
Area of Science:
- Physiology
- Hyperbaric Medicine
- Sports Science
Background:
- Decompression sickness (DCS) is a risk for divers.
- Bubble formation during dives is a key factor in DCS.
- Hydration status can influence physiological responses to diving.
Purpose of the Study:
- To determine if pre-dive hydration reduces bubble formation.
- To assess the impact of prehydration on plasma volume (PV), water balance, and plasma surface tension (ST).
Main Methods:
- Eight military divers underwent a crossover trial with and without pre-dive hydration.
- Hydration involved a 1300 ml saline-glucose beverage 90 minutes pre-dive.
- Diving protocol: 30 msw for 30 min, followed by a 9 min stop at 3 msw.
- Bubble formation assessed via precordial pulsed Doppler; PV, body weight, and urine volume monitored.
Main Results:
- Significantly lower bubble activity observed with prehydration (protocol 1) versus no prehydration (protocol 2).
- Prehydration increased PV by 3.5% post-ingestion, preventing post-dive decrease seen in protocol 2.
- Prehydration reduced body weight loss and negative water balance compared to the control.
Conclusions:
- Pre-dive oral hydration effectively decreases circulatory bubbles, lowering DCS risk.
- Prehydration helps attenuate dehydration and prevent hypovolemia during diving.
- Plasma surface tension was not affected by hydration or diving in this study.
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