Propofol-fentanyl anaesthesia for coronary bypass surgery in patients with good left ventricular function

The haemodynamic effects of propofol-fentanyl anaesthesia for elective coronary bypass surgery were studied in 15 patients with good left ventricular function. The induction dose of propofol was 1.5 mg kg-1. The mean infusion rate during maintenance was 5.15 mg kg-1 h-1 (range 4.05-8.82 mg kg-1 h-1). The total dose of fentanyl given in the pre-bypass period was 32 micrograms kg-1. Induction of anaesthesia was associated with significant (P less than 0.05) decreases in systolic (-28%) and diastolic (-23%) pressures, systemic vascular resistance (-25%) and left ventricular stroke work index (LVSWI) (-32%). The decrease in LVSWI (P less than 0.05) during induction and maintenance with unchanged filling pressures, indicated myocardial depression. Clinical signs that could reflect myocardial ischaemia were not observed during the operation. There were no changes in the concentrations of the cardiac enzymes in the postoperative period and ECG morphology was unchanged.