Propofol versus remifentanil for monitored anaesthesia care during colonoscopy

Background and objective: We conducted an open, prospective, randomized study to compare the efficacy, safety and recovery characteristics of remifentanil or propofol during monitored anaesthesia care in patients undergoing colonoscopy.

Methods: Forty patients were randomly assigned to receive either propofol (1 mgk g(-1) followed by 10 mg kg(-1) h(-1), n = 20) or remifentanil (0.5 mug kg(-1) followed by 0.2 mug kg(-1) min(-1), n = 20). The infusion rate was subsequently adapted to clinical needs.

Results: In the propofol group, arterial pressure and heart rate decreased significantly from the baseline. These variables remained unchanged in the remifentanil group, but hypoventilation occurred in 55% of patients. Early recovery was delayed in the propofol group (P <0.002). Recovery of cognitive and psychomotor functions was faster in the remifentanil group. Fifteen minutes after anaesthesia, the Digit Symbol Substitution Test score was 28.6 +/- 12.8 versus 36.2 +/- 9.4 and the Trieger Dot Test score was 25.6 +/- 8.1 versus 18.7 +/- 4.1 in the propofol and remifentanil groups, respectively (both P <0.05). Patient satisfaction, using a visual analogue scale, was higher in the propofol group (96 +/- 7 versus 77 +/- 21, P <0.001).

Conclusions: Remifentanil proved efficient in reducing pain during colonoscopy. Emergence times were shorter and the recovery of cognitive function was faster with remifentanil compared with propofol. Remifentanil provided a smoother haemodynamic profile than propofol; however, the frequent occurrence of remifentanil-induced hypoventilation requires the cautious administration of this agent.