Comparison of propofol and thiopentone as induction agents for laparoscopy.

Fifty two patients for laparoscopy were randomly divided into two groups and induced with propofol 2 mgkg-1 or thiopentone 4 mgkg-1. The two groups were similar for race, age, weight, premedication and duration of operation. General anaesthesia with endotracheal intubation, nitrous oxide/oxygen with 0.5% halothane and muscle relaxation with suxamethonium was used throughout. Induction times were similar for both groups. The systolic, diastolic blood pressures and heart rates of both groups fell significantly from baseline values two minutes after induction. The fall in systolic blood pressure was greater with propofol (p less than 0.01). Following intubation the rise in systolic, diastolic blood pressures and heart rate above baseline values were greater with thiopentone (p less than 0.001 for all three variables). Discomfort on injection and involuntary movements were significantly more common with propofol. Laryngospasm was significantly more common with thiopentone. Patients given propofol could sit up unaided earlier after the anaesthesia (p less than 0.01). There was no difference in eye opening and orientation time.