Influence of sufentanil on propofol anesthesia using a target controlled infusion system.

We assessed the effect of three different dosings of sufentanil on induction, maintenance and recovery characteristics of a propofol target controlled infusion anesthesia in twenty-four patients scheduled for laparoscopic cholecystectomy. The patients were allocated randomly to receive a sufentanil bolus of 15, 30 or 45 micrograms followed by a continuous infusion of sufentanil of 15, 30 or 45 micrograms/h respectively. The maintenance propofol anesthesia was titrated to achieve hemodynamic stability. Recovery was assessed by noting the times at which patients opened their eyes and correctly gave their birth date. The predicted propofol blood concentration was noted at loss of consciousness, at different times of surgery and at the recovery events. A threefold increase of sufentanil dosing did not significantly affect the induction times nor recovery times following propofol anesthesia. The recovery parameters were determined by the total amount of propofol administered. The mean predicted propofol blood concentrations measured at induction, during maintenance and recovery (opening of eyes) were 3.4-3.9 micrograms/ml, 4.0-4.8 micrograms/ml and 1.1-1.4 micrograms/ml respectively and were not significantly influenced by the sufentanil dosing.