Equilibration, distribution, and elimination of a single dose of intravenous ethanol in dogs with intact renal...

We infused 11 mmol/kg of intravenous ethanol into dogs with either intact renal function (n = 5) or ureteral ligation (n = 7), and studied by frequent blood sampling and by urine collection the time and mode of ethanol equilibration, the elimination parameters, and the comparison of observed equilibrated plasma ethanol levels to levels predicted either by linear or by nonlinear kinetics. Equilibration time was 25 min or less, renal fraction of elimination was less than 5% of total elimination, and both linear (elimination rate) and nonlinear (Vmax and Km) elimination parameters were not different between dogs with intact renal function and dogs with anuria. Serum sodium concentration did not change throughout the experiments, eliminating the hypothesis that acute ethanol load creates clinically significant temporary osmotic water transfer from the intracellular into the extracellular compartment. Distribution volumes of ethanol from linear kinetics were slightly, but not statistically, greater than volumes from nonlinear kinetics. Equilibrated plasma ethanol levels predicted by linear kinetics agreed closely with observed levels greater than 4 mmol/liter, but underestimated observed levels less than 4 mmol/liter. Equilibrated plasma ethanol levels predicted by nonlinear kinetics agreed with observed levels throughout the range of observed concentrations. The use of linear kinetics to predict blood ethanol levels should be limited to the pseudolinear portion of the blood alcohol curve.