A COMPARISON OF THE HEMODYNAMIC-EFFECTS OF PROPOFOL AND ISOFLURANE INPREGNANT EWES

The purpose of this study was to compare the effects of inhaled isoflu rane and a constant infusion of propofol on maternal haemodynamics and uterine arterial and umbilical venous flows in pregnant ewes. Late te rm pregnant ewes (n = 5) were randomly assigned to receive either inha led isoflurane or an intravenous infusion of propofol for 1 h, each on separate occasions. Maternal systemic arterial, right atrial and pulm onary arterial blood pressures, cardiac index, systemic vascular resis tance index, stroke volume index, heart rate, and uterine arterial and umbilical venous flows were determined over the 1 h period of each tr eatment. Data were analysed using an univariate analysis of variance f or repeated measures performed on the ranks of the data. Propofol anae sthetized ewes had significantly higher heart rate (P = 0.0040), mean arterial pressure (P=0.0003) and cardiac index (P=0.0475) compared to isoflurane anaesthetized ewes. There were no significant differences i n uterine arterial flows, umbilical venous flows, or other measured va riables. Continuous propofol infusions maintain maternal haemodynamics at significantly higher levels than does inhaled isoflurane, while ut erine arterial and umbilical venous flows do not differ significantly.