Inclusion Criteria:  Age is between 18 and 85 years ASA I-III levels; Patients undergone elective ERCP surgery, non-intubation patients;  Exclusion Criteria:  Chronic pain with long-term use of analgesics, psychotropic substances (including opioids, NSAIDs, sedatives, antidepressants), alcohol abusers, with known drug allergy; BMI<18 or BMI>30; Previous abnormal surgical anesthesia recovery history; Hypertension or systolic blood pressure greater than 160 mmHg or diastolic blood pressure greater than 95 mmHg when the patient admission to the operating room Suffering from esophageal reflux; • Sedatives, analgesics and antipruritic drugs were used 24 hours before operation; Expected difficult intubation ; Opioids allergy history; Take monoamine oxidase inhibitor or antidepressant within 15 days; Pregnant or parturient women; Involved in other drug trials within three months; Patients who can not communicate well with the researcher