Dobutamine during anesthesia of patients at risk for heart failure. A controlled prospective multicenter study of 93 surgical patients over 64 years of age

Abstract Most anaesthetic agents cause cardiac depression possibly hazardous in the elderly, especially in presence of a poor cardiac reserve. Ninety-three patients undergoing non cardiac surgery lasting more than 90 min. were entered in a double-blind multicentre randomized trial. They were 65 year old or more and unaffected by evolutive angina pectoris. After insertion of a Swan Ganz catheter and an arterial cannula, anaesthesia was induced by thiopentone, fentanyl and 02/nitrous oxide (50%). Forty-five patients were infused dobutamine 7 micrograms.kg-1.min-1 (group D) from 10 min. after induction till the completion of surgery. Forty-eight patients received a placebo (group P). Haemodynamic parameters were recorded throughout anaesthesia and at its emergence. After induction, heart rate, pulmonary capillary wedge pressure and mean pulmonary artery pressure did not change significantly; mean arterial pressure, cardiac index, stroke index and left ventricular stroke work index decreased by 21, 33, 28 and 42% respectively (p less than 0.001); systemic and pulmonary arterial resistances increased by 12 and 37% respectively (p less than 0.001). In group P, these changes persisted throughout the procedure but, 30 min after extubation, cardiac index returned to control levels due to a 25% increase in heart rate; in this group 4 patients presented with both perioperative low cardiac output and persistent postoperative confusion. With dobutamine, haemodynamic parameters returned to preoperative values and heart rate increased by 12 b.min-1. More arrhythmias and hypertensive episodes but less hypotensions occurred in group D. Substantial haemodynamic changes occur during anaesthesia and surgery in elderly patients. Dobutamine corrects the peroperative decrease in cardiac output and blood pressure, and might prevent postoperative neurological disorders.