Alfentanil v. isoflurane for outpatient arthroscopy

Alfentanil by continuous intravenous infusion and isoflurane have been compared as anaesthetic agents for outpatient arthroscopy. In 42 patients, divided at random into two groups, anaesthesia was induced with methohexitone and vecuronium bromide, and, after intubation, maintained with nitrous oxide 66% in oxygen combined with alfentanil or isoflurane. Alfentanil was given before intubation (1 mg), as a loading dose before starting surgery (50 micrograms kg-1) and by a continuous infusion at a rate of 1 microgram kg-1 min-1. Isoflurane was given in a concentration of 0.9% as a maintenance dose. Awakening from anaesthesia was more rapid with alfentanil than with isoflurane. Recovery tests were applied in the recovery room. Both anaesthetic techniques provided satisfactory anaesthesia and rapid recovery. All patients but one were content with the anaesthesia. The patients who received isoflurane scored better in the recovery tests in the first 3 h, but after 3 h there was no difference between the groups. The alfentanil group showed a higher incidence of nausea and/or vomiting: 45% compared to 14% in the isoflurane group.