Recovery characteristics of sevoflurane- or propofol-based anaesthesia for day-care surgery

Background: Sevoflurane has a low blood-gas partition coefficient resulting in a rapid recovery. Few studies have examined the maintenance and recovery characteristics of sevoflurane compared with propofol in a standardized outpatient population. Methods: The study was a multicentre study performed in 10 centres. One hundred and sixty-nine elective outpatients due for knee-arthroscopy received 100 mg diclofenac rectally as pain prophylaxis prior to induction of general anaesthesia with fentanyl 1.0-1.5 mu g/kg+propofol 2.0-2.5 mg/kg iv. Anaesthesia was maintained with 60% nitrous oxide in oxygen through a laryngeal mask and continuous administration of either: sevoflurane (group S) or propofol infusion (group P) in order to maintain stable haemodynamics. Data of postoperative function and side-effects st ere collected in a double-blind design, including a patient interview after 24 h. Results: The sevoflurane patients had a significantly faster emergence from anaesthesia, with response to commands at 6.9+/-0.4 min versus 8.2+/-0.4 min in the propofol group (P<0.05, mean+/-SD). At 15 min after surgery, group S had a better score in the digit symbol substitution test and felt less confused in a visual analogue scale test compared with group P (P<0.05). Peroperative bradycardia, nausea and vomiting and late postoperative dizziness were more common in group S. In the sevoflurane group, 32% had nausea or vomiting in the 24 h observation period compared with 18% for propofol (P<0.05). There was no difference between group S and group P in postoperative pain, eligibility for recovery room discharge (75+/-12 versus 70+/-11 min) or home-readiness (155+/-12 versus 143+/-11 min). Conclusion: Maintenance of anaesthesia with sevoflurane results in a more rapid emergence, but a higher incidence of nausea and vomiting compared with propofol. The side-effects were minor in our study, and did not result in any difference in time to discharge from the recovery ward or the hospital.