Bispectral Index-Guided Versus Fixed Dose Administration of Desflurane During Balanced Anesthesia With Remifentanil

Balanced anesthesia combining volatile anesthetics and opioids is commonly used in modern anesthesia. The purpose of this study is to compare two methods of administering desflurane, an volatile anesthetic during balanced anesthesia. The investigators hypothesized that administering desflurane at 1 MAC (minimum alveolar concentration) during balanced anesthesia will be more beneficial in terms of stability of the patient's vital signs and hypnotic depth than administering desflurane according to the patient's BIS (bispectral index) value.