The acute dose-related effects of ethanol on right ventricular function in anesthetized dogs

Abstract

The acute dose-related effects of small to moderate doses of ethanol on right ventricular functioning were studied on 18 anesthetized, artificially ventilated dogs in 39 sessions. Diluted ethanol (from 25–37.5%) was infused during 40 minutes, yielding total doses of 1.0 g/kg ( n = 15), and 1.5 g/kg ( n = 12) with corresponding venous blood ethanol peak concentrations of 1.38 ± 0.25 and 2.41 ± 0.31 mg/ml, respectively. Heart rate increased up to 16% in groups receiving ethanol. In the control group receiving the equivalent volume of saline ( n = 12) heart rate decreased 14%. Pulmonary arterial systolic pressure increased from 24 ± 3 to 27 ± 3 mmHg and diastolic pressure from 11 ± 2 to 14 ± 4 mmHg ( p < 0.05) when the ethanol dose was 1.0 g/kg. The pulmonary arterial resistance increased from 620 ± 135 to 805 ± 185 dyn·s·cm −5 ( p < 0.01). The peak d P/d t decreased maximally by 20% with increasing ethanol doses. Stroke volume decreased maximally by 14% but due to the increase in heart rate, cardiac output even increased. The changes in end-diastolic volume and pressure were not significant. Hence, the ethanol increased heart rate and afterload of the right ventricle but depressed the myocardium.