Feasibility of application of bispectral index to titrating desflurane or sevoflurane anesthesia

Objective To assess the feasibility of using bispectral index (BIS) to guidance of desflurane or sevoflurane anesthesiaMethods Forty ASA Ⅰ-Ⅱ patients were randomly assigned to four groups, After a induction of propofol 2-2·5mg·kg -1 and fentanyl 2ug·kg -1, laryngoscopy and intubation were facilitated with intravenous vecuronium 01mg·kg -1,and anesthesia was maintained with either desflurane or sevoflurane in combination with 60% nitrous oxide In control groups, the anesthesiologists were blinded to the BIS value, and the volatile anesthetics were administered according to their clinical experience In BIS-titrated groups, the volatile anesthetics were titrated to maintain the BIS value at about 60Results During the maintenance period, the SBP in BIS-titrated groups was higher than that in control groups, while SBP fluctuation was less in control groups than that in BIS-titrated groups The requirements of volatile anesthetics were lower in BIS-titrated groups than those in control groupsConclusions In spite of predicting the sedative effect of desflurane or sevoflurane, BIS can not titrate desflurane or sevoflurane anesthesia