Clinical Research Directory

Inclusion Criteria: 1. ASA I-II, patients 2. aged 18-65 years old; 3. Fundus surgery to be performed under general anesthesia ; 4. The expected duration of surgery is about 30-120 min ; 5. BMI: 18-30 kg/m2 ; 6. Those who signed the informed consent form and volunteered to participate in this trial Exclusion Criteria: 1. Patients with known or suspected genetic susceptibility to malignant hyperthermia; 2. Patients with history of asthma; 3. Patients with severe heart diseases (NYHA ≥ III, severe arrhythmia, etc.) and cerebral or pulmonary diseases, liver or kidney dysfunction; or with unstable vital signs; 4. Patients with history of long-term narcotic analgesics application, including sedative and antidepressant drugs; 5. Patients with history of psychotropic drug abuse within 3 months; 6. Patients with long-term alcohol abuse; 7. People with mental disorder and unable to communicate normally;