Cardiovascular effects of propofol during coronary ligation in anesthetized dogs

Under different infusion rates in normal hearts and hearts with coronary ligation, the hemodynamic effects of propofol were measured in a coronary artery ligation model in twelve mongrel dogs. Propofol was given by 10 mg/kg intravenous bolus followed by 30 min infusion in succession with 20 mg/kg/hr, 40 mg/kg/hr and 80 mg/kg/hr in both normal hearts and hearts with coronary ligation. The range of blood concentrations in our study is 2.19 +/- 0.56 microgram/ml to 15.78 +/- 3.31 micrograms/ml. After ligation at 1 cm below first diagonal branch of left anterior descending artery (LAD) obvious cardiovascular changes were seen in a few seconds. However, non-significant hemodynamic changes were demonstrated between pre-ligated and 30 min after ligation. With increasing blood propofol concentrations, there was significant negative correlation (p < 0.01) in mean arterial pressure (MAP), cardiac output (CO) and heart rate (HR) but central venous pressure (CVP) and pulmonary arterial occlusion pressure (PAOP) decreased non-significantly with increasing propofol concentrations in both non-ligated and ligated groups. Propofol infusion up to 80 mg/kg/hr did not decrease MAP, CO and systemic vascular resistance (SVR) further in hearts with coronary ligation than normal hearts in our study. SVR and pulmonary vascular resistance (PVR) changed non-significantly between each groups even in blood concentration as high as 15 micrograms/ml. We conclude that propofol depresses myocardial function associated with increasing blood propofol concentrations despite stable SVR and PVR. The hemodynamic effects of propofol were similar in the normal hearts and hearts with coronary ligation.(ABSTRACT TRUNCATED AT 250 WORDS)