Effects of hypothermia on disappearance of ethanol from arterial blood

¹ Department of Cardiovascular Surgery, Banting Institute, University of Toronto, Toronto, Ontario, Canada

Normothermic and hypothermic (24 C) dogs were given ethanol intravenously and the rates of accumulation and disappearance of ethanol from arterial blood were studied, with the following results: 1) The rate of decrease of ethanol concentration in the arterial blood in normo- and hypothermic dogs was similar. 2) Extrapolation of concentration vs. time curves after equilibration showed reduction in apparent total available body-water space in hypothermic dogs. 3) Equilibration took twice as long in hypothermic as in normothermic dogs. 4) A fourfold increase of tidal volume did not affect the disappearance of ethanol in a normothermic dog. 5) The disappearance rate of ethanol in hypothermic dogs was decreased by hexamethonium or a small dose of epinephrine, but normalized by a pressor dose of epinephrine. It is suggested that the effects of hypothermia on hepatic blood flow and on alcohol dehydrogenase activity tend to cancel each other out. Modification of the rate of alcohol disappearance by hexamethonium and by epinephrine probably results from changes in hepatic circulation.

Key Words: ethanol metabolism • blood ethanol levels • hepatic perfusion • body-water space • hexamethonium epinephrine • effect of drugs on hepatic circulation • disappearance of ethanol in hypothermia • intravenous ethanol

Submitted on August 31, 1964