Background: Sevoflurane has a lower blood:gas partition coefficient than isoflurane, which may cause a more rapid recovery from anesthesia; it also might cause faster emergence times than for propofol-based anesthesia. We evaluated a database that included recovery endpoints from controlled, randomized, prospective studies sponsored by Abbott Laboratories that compared sevoflurane to isoflurane or propofol when extubation was planned immediately after completion of elective surgery in adult patients.
Methods: Sevoflurane was compared to isoflurane in eight studies (N=2,008) and to propofol in three studies (N=436). Analysis of variance was applied using least squares method mean values to calculate the pooled mean difference in recovery endpoints between primary anesthetics. The effects of patient age and case duration also were determined.
Results: Sevoflurane resulted in statistically significant shorter times to emergence (-3.3 min), response to command (-3.1 min), orientation (-4.0 min) and first analgesic (-8.9 min) but not time to eligibility for discharge (-1.7 min) compared to isoflurane (mean difference). Times to recovery endpoints increased with increasing case duration with isoflurane but not with sevoflurane (patients receiving isoflurane took 4-5 min more to emerge and respond to commands and 8.6 min more to achieve orientation during cases longer than 3 hr in duration than those receiving sevoflurane). Patients older than 65 yr had longer times to orientation, but within any age group, orientation was always faster after sevoflurane. There were no differences in recovery times between sevoflurane and propofol.
Conclusions: Recovery from sevoflurane was 3-4 min faster than with isoflurane in all age groups, and the difference was magnified in longer-duration surgical cases (> 3 hr).