Effect of Nitrous Oxide on Bispectral Index during Sevoflurane Anesthesia / 대한마취과학회지

ABSTRACT

BACKGROUND: Nitrous oxide is generally avoided in order to prevent either hypoxia or graft dislodgment during tympanoplasty. The aim of this study was to investigate the effect of nitrous oxide on the bispectral index during sevoflurane anesthesia at the anesthetic dose. METHODS: The bispectral index was continually measured during nitrous oxide-oxygen-sevoflurane anesthesia, discontinuation of nitrous oxide and the reintroduction of nitrous oxide. RESULTS: The bispectral index of nitrous oxide-oxygen-sevoflurane anesthesia increased after discontinuing the nitrous oxide and decreased after its reintroduction. CONCLUSIONS: Nitrous oxide decreased the bispectral index of nitrous oxide-oxygen-sevoflurane anesthesia compared with oxygen-sevoflurane anesthesia at the anesthetic dose.