EFFECT OF VANCOMYCIN INFUSION ON CARDIAC-FUNCTION IN PATIENTS SCHEDULED FOR CARDIAC OPERATION

Patients scheduled for cardiac operation often receive vancomycin befo re the operation to decrease postoperative staphylococcal wound infect ions. In animal studies, vancomycin depressed cardiac function approxi mately 15%. Because of the potentially serious consequences of myocard ial depression in patients undergoing cardiac operation, we examined t he effect of vancomycin infusion on cardiac hemodynamics in patients s cheduled for cardiac operation. Patients who were scheduled for cardia c operation and vancomycin prophylaxis were enrolled in our study. Aft er baseline cardiac output, mean arterial pressure, central venous pre ssure, and pulmonary capillary wedge pressure were measured, 1 gm of v ancomycin HCl was infused over 1 hour. Cardiac output, mean arterial p ressure, central venous pressure, and pulmonary capillary wedge pressu re were measured at 15, 30, 60, 90, and 120 minutes after the start of the infusion. In the 46 patients that completed the study, no signifi cant change was observed in cardiac output or systemic vascular resist ance at any time when compared with baseline. Mean arterial pressure i ncreased significantly (p = 0.03) between baseline (90.8 +/- 2.4 stand ard error of mean) and 90 minutes (94.1 +/- 2.4 standard error of mean ). One patient had a transient 30% fall in mean arterial pressure and systemic vascular resistance with facial flushing during the infusion. In conclusion, we found that vancomycin infusion over 1 hour in patie nts before cardiac operation is safe and not associated with cardiac d epression.