Feasibility of application of bispectral index to titrate Sevoflurane anesthesia in intracranial operations

[Objective] To assess the feasibility of using bispectral index (BIS) to guide Sevoflurane anesthesia in intracranial operations. [Methods] Forty ASA Ⅰ~Ⅱpatients were randomly assigned to two groups. After an induction of midazolam 0.1 mg/kg, propofol 2 mg/kg and fentanyl 4 μg/kg, laryngoscopy and intubation were facilitated within travenous vecuronium 0.1 mg/kg, and anesthesia was maintained with sevoflurane. In control groups, the anesthesiologists were blinded to BIS value, and the volatile anesthetics were administered according to physicians' clinical experience. In BIS-titrated groups, the volatile anesthetics were titrated to maintain the BIS value at about (55±5). [Results] During the maintenance period, the MAP in BIS-titrated groups was higher than that in control groups, while MAP fluctuation was greater in control groups than that in BIS-titrated groups. The requirements of volatile anesthetics were lower in BIS-titrated groups than those in control group. [Conclusions] BIS can not only predict the sedative effect of Sevoflurane, but also titrate Sevoflurane anesthesia.