Effect of different rates of infusion of propofol for induction of anaesthesia in elderly patients

Abstract

The effect of changing the rate of infusion of propofol for induction of anaesthesia was studied in 60 elderly patients. Propofol was administered at 300, 600 or 1200 ml h-1 until loss of consciousness (as judged by loss of verbal contact with the patient) had been achieved. The duration of induction was significantly longer (P less than 0.001) with the slower infusion rates (104, 68 and 51 s), but the total dose used was significantly less (P less than 0.001) in these patients (1.2, 1.6 and 2.5 mg kg-1, respectively). The decrease in systolic and diastolic arterial pressure was significantly less in the 300-ml h-1 group at the end of induction and immediately after induction (P less than 0.01). The incidence of apnoea was also significantly less in the slower infusion group.