Single-breath induction of anesthesia: comparison of enflurane and sevoflurane

In this study induction of anesthesia using the single-breath technique with either enflurane or sevoflurane in oxygen was compared. Each group consisted of 16 unpremedicated volunteers who breathed approximately 1.7 minimum alveolar concentration (MAC) equivalents of either vapor. There were no significant differences in the cardiovascular and respiratory variables monitored. The induction of anesthesia with enflurane (141±41 s) required significantly more time than with sevoflurane (118±25 s). The enflurane group was associated with significantly more problems during induction, and showed moderate or sometimes severe excitatory movements of the extremities and/or coughing. Subjects in the enflurane group described the induction of anesthesia as less pleasant than in the sevoflurane group. We concluded that enflurane was less suitable for single-breath induction of anesthesia compared with sevoflurane.