Alfentanil or fentanyl during isoflurane-based anaesthesia for day-care knee arthroscopy?

Forty patients agreed to participate in a study to compare whether fentanyl or alfentanil used as analgesic is associated with quicker recovery following anaesthesia for outpatient arthroscopy procedure. Psychomotor tests including choice reaction time (CRT), perceptive accuracy test (PAT) and finger tapping test (FTT) were done prior to induction of anaesthesia with propofol (2-3 mg.kg-1). Patients were then divided into two groups: Group F (fentanyl) received 0.1 mg fentanyl prior to start of surgery and thereafter 0.05 mg every 30 min during the procedure. Group A (alfentanil) received 0.5 mg alfentanil prior to the onset of surgery and 0.25 mg every 15 min thereafter. Anaesthesia was then maintained using isoflurane (0.5-2%) in oxygen and air (FiO2 0.33) during spontaneous respiration with a face mask in a Bain's system. Psychomotor tests were repeated every 45 min postoperatively. Clinical recovery, visual analogue pain intensity score (VAS) and time to discharge home were also assessed by a nurse blind to the method used. Patients in Group A returned to baseline values on the FTT after 90 min while those in Group F did not return to baseline values until 135 min after the end of the operation. Clinical recovery and time to discharge home ("home ready") were also significantly longer in Group F. There was no difference in recovery as seen in the PAT and CRT between the groups. Also, there was no difference in the incidence of side effects and the pain intensity (VAS) scores were similar in the two groups at all time periods.(ABSTRACT TRUNCATED AT 250 WORDS)