Effects of Remimazolam on Intraoperative Blood Pressure Control in Interventional Cerebral Aneurysm Coil Embolization

INTERVENTION: Drug : In the test group (group B), anesthesia is maintained with remimazolam after induction of anesthesia with remimazolam (trade name: byfavo). 1 vial of byfavo is dissolved in 50 mL of physiological saline and diluted to a concentration of 1 mg/mL. It is infused at a rate of 6 to 12 mg/kg/hr (0.1 to 0.2 mg/kg/min, 360 to 720 mL/hr for an adult patient weighing 60 kg) until BIS (bispectral index) reaches 40 to 60 inject. After induction of anesthesia, it is maintained at 1‐2 mg/kg/hr (60‐120 mL/hr for 60 kg patients). The injection concentration can be adjusted according to the hemodynamic condition of the patient and the depth of anesthesia. In the control group (group S), anesthesia is induced by a bolus injection of 1‐2.5 mg/kg of propofol. Afterwards anesthesia is maintained with sevoflurane at a concentration of 1.0 MAC. The amount and concentration of injection can be adjusted according to the patient's hemodynamic condition and depth of anesthesia. CONDITION: Diseases of the circulatory system PRIMARY OUTCOME: Intraoperative blood pressure SECONDARY OUTCOME: Intraoperative heart rate, vasopressor usage, mortality within 30 days POD, delirium 7days POD, AKI 7 days POD (according to KDIGO guideline) INCLUSION CRITERIA: Patients over age 19 undergoing elective cerebral aneurysm coil embolization at Korea University hospital under general anesthesia, who have agreed to terms.