The use of alfentanil (Rapifen) by infusion for surgical procedures of long duration.

The use of alfentanil was studied in 49 patients undergoing surgery with a duration of at least 90 minutes. Induction was performed with droperidol (Dehydrobenzperidol) and etomidate (Hypnomidate), maintenance with nitrous oxide/oxygen 2:1 and alfentanil. Alfentanil was administered as an initial bolus of 2-3 mg depending on the body weight of the patient, immediately followed by a continuous infusion of 0.75 microgram/kg/min. In case a stressful or painful event in surgery caused inadequate analgesia, additional increments of 1 mg of alfentanil were administered. Anesthesia was considered to be good in 90% of the patients. The number of additional increments needed did not increase as the anesthetic procedure progressed in time. In virtually all patients postoperative recovery was fast and not related to the number of increments. It is concluded that alfentanil infusion for longer procedures in combination with nitrous oxide/oxygen provided a good and easy method for maintaining a satisfactory level of analgesia.