A COMPARISON OF PENTAZOCINE AND PETHIDINE IN PATIENTS WITH PAIN FOLLOWING CHOLECYSTECTOMY

Forty-nine patients who had undergone cholecystectomy were investigatedin a double-blind, between-patient single-dose comparison ofpentazocine and pethidine. Patients were matched for age, sex,weight and pre-operative blood pressure, and received pentazocine0.3 mg/kg body weight or pethidine 0.5 mg/kg by intravenousinjection. All measurements were made by the same observersin the first 3 hours after the operation. Systolic and diastolicpressures remained unchanged in the pentazocine group, but therewas a significant fall of about 10 per cent in both systolicand diastolic pressures 90 minutes after the injection of pethidine.Although pethidine gave slightly better analgesia, the degreeof sedation was significantly greater, and side effects occurredmore frequently. It is concluded that pentazocine may have advantagesover pethidine especially in the immediate postoperative periodwhen the cardiovascular system is unstable.