The effect of increasing the dose of buprenorphine on the haemodynamic response associated with tracheal intubation

The effect of buprenorphine on the haemodynamic response to tracheal intubation was studied at two dose levels, 2.5 μg.kg^-1 and 5 μg.kg^-1, in a placebo-controlled double-blind trial in 75 patients undergoing laparoscopic cholecystectomy. The study drugs were administered intravenously 8 min before induction of anaesthesia with thiopentone 5 mg.kg^-1 and vecuronium 0.1 mg/kg^-1. Buprenorphine 2.5 μg.kg^-1 caused 50% attenuation of the blood pressure response whereas 5 μg/kg^-1 caused 70% attenuation compared to the saline placebo. The maximum increase in heart rate was 14% of the control value after 2.5 μg.kg^-1 and 11% after 5 μg/kg^-1 of buprenorphine. A significant difference in heart rate was observed between the two buprenorphine groups at 5 and 10 min after intubation. Blood pressure and heart rate both showed a significant fall from baseline values 10 min after intubation in both buprenorphine groups, with the changes being greater in the 5 μg.kg^-1 group. We recommend the use of 2.5 μg.kg^-1 buprenorphine for attenuation of the hypertensive response to intubation in major abdominal surgery.