THE EFFECT OF BLOOD-ALCOHOL ON THE INITIAL RESPONSES TO COLD-WATER IMMERSION IN HUMANS

Many drowning victims have alcohol in their blood, but it is not clear whether there is a causal relationship. This study examined the effec t of moderate alcohol consumption on the initial responses to cold wat er immersion. Sixteen subjects wearing swimming costumes undertook two , 3-min head-out seated immersions in water at 15 degrees C. One hour before immersion, subjects drank either 3.7 ml . kg body water(-1) of 40% v:v alcohol as vodka, or an equivalent volume of water (control) m ixed with squash. On immersion, the average blood alcohol concentratio n was 23 mmol . l(-1) (105 mg . 100 ml(-1)) after alcohol consumption and zero in the control condition. Respiratory frequency in the first 20s of immersion was found to be reduced (P < 0.05) by 10% (a total of 2-3 breaths) after alcohol consumption compared to the control immers ion. Tidal volume, heart rate, rectal temperature and skin temperature s did not differ significantly between immersions. It is concluded tha t moderate alcohol consumption does not attenuate the initial ''cold s hock'' responses to a practically significant extent and is thus unlik ely to reduce the risk of drowning on immersion in cold water.