Inclusion Criteria:  aged 18 years or older scheduled for interventional neurosurgery of cerebrovascular disorders under general anesthesia  Exclusion Criteria:  American Society of Anesthesiologists class Ⅲ or higher Hunt-Hess class Ⅲ or higher body mass index (BMI) < 18 kg/㎡ or > 30kg/㎡ large or giant cerebral aneurysms with diameters greater than 15mm and minor cerebral aneurysms with diameters less than 3mm posterior circulation infarction recurrence of an cerebral aneurysms after endovascular procedures or surgical clipping severe abnormal coagulation function, severe liver and kidney function damage, or combined with heart and respiratory system failure be allergic or likely to be allergic to the study drugs participate in other clinical researchers within 3 months history of neurological or psychiatric diseases existed or suspected abuse of drug or alcohol use of sedative or analgesics before surgery patients with difficulty in communication