[Hemodynamic effects of propofol induction administered with target controlled infusion pump in patients scheduled for open heart surgery].

Target controlled infusion systems have been developed to provide improved convenience and control during intravenous anaesthesia. The anaesthetist sets and adjust the target blood concentration and depth of anaesthesia--as required on clinical grounds. Infusion rates are altered automatically according to a validated pharmacokinetic model. Haemodynamic effects during induction of anaesthesia with target controlled infusion pump have been documented in this prospective study. Twenty patients scheduled for open heart surgery. Mean age 62.2 +/- 9.93 years. The surgical procedures were: 16 coronary bypass, 2 artificial valve replacement, 2 coronary bypass combined valve replacement. Anaesthesia was induced with alfentanil, 20-40 micrograms/kg, and propofol administered with target control infusion pump, 1.5-4 micrograms/ml target concentration. Pulse contour analysis was used for haemodynamic measurements. They were repeated before induction (T0), after induction--before intubation (T1), after intubation in two minutes intervals (T2-T5). Compared with values obtained in awake patients, there was a significant decrease in mean arterial pressure (-30%), in cardiac output (-25%), in heart rate (-8%), in vascular resistance (-9%), in contractility (-37.4%), in stroke volume (-17.5%). No ECG changes were observed during that period. The haemodynamic changes observed do not differ from the published data in patients presenting for cardiac surgery and anaesthetized with manually controlled infusion techniques using propofol.