[The need for alfentanyl in total intravenous anesthesia. Comparison between laparoscopic cholecystectomy and...

To quantify intraoperative consumption of alfentanil in cholecystectomy by laparoscopy or by the traditional approach; to evaluate its relation to time until extubation, presence and intensity of postoperative pain and vomiting.

Prospective, non randomized study. Forty female physical status ASA I-II patients between 18 and 60 years of age scheduled to undergo subcostal cholecystectomy by subcostal laparotomy (group CSL, n = 20) or by laparoscopy (group CL, n = 20). Total intravenous anesthesia with propofol, alfentanil and atracurium was provided. A continuous infusion of alfentamil 1 microgram/kg/min was used, with a supplement of 7 micrograms/kg when mean arterial pressure (MAP) rose more than 10% above baseline or with a supplement of 14 micrograms/kg when MAP rose 20% or more above baseline. Variables measured were intraoperative alfentanil requirements, time until extubation, presence and intensity of pain in the immediate postoperative period and incidence of vomiting.

Alfentanil consumption was 1.81 and 1.63 micrograms/kg/min and time to extubation was 17.5 and 14.05 min in the CL and CSL groups (p < 0.05), respectively. There was less pain in the early postoperative period in the CL group (36.8% for the CL patients as opposed to 85% in the CSL group, p < 0.01) and pain was less intense (p < 0.01). The incidence of vomiting was 42.1% in group CL and 25% in group CSL (p = NS).

Insufflating the pneumoperitoneum for laparoscopic surgery brings about hemodynamic changes that increase intraoperative consumption of alfentanil during surgery, and this can lead to delayed awakening.