Intravenous infusion of lidocaine significantly reduces propofol dose for ERCP and improve patients' recovery after ERCP.

This study divide patients into two groups, one will be given lidocaine; another group was given placebo . to observe two groups of patients blood pressure, body movement, and propofol dosage , and the difference in operator satisfaction, and how many people need to give fentanyl again; and two groups of patients after the operation of the reaction, if there are dizziness, nausea, and other adverse reactions; finally, the differences of these two schemes in different populations were analyzed, and the rationalization and individualized medication will be put forward.

Inclusion Criteria:Inpatients aged >18 years who were scheduled for ERCP at Qilu hospital.

Exclusion Criteria:

• Patients with ASA class 4 or 5,
• Patients with pre-existing hypoxaemia (SpO2<90%),
• Patients with hypotension (SBP<90mmHg)
• Patients with bradycardia (HR<50 bpm)
• patients with severe chronic renal failure (creatinine clearance<30 ml/min)
• patients with uncontrolled hypertension (systolic blood pressure>170 mm Hg, diastolic blood pressure>100 mm Hg)
• patients with pregnancy or lactation
• Patients hemodynamically unstable
• Patients unable to give informed consent
• Patients with a history of drug allergies;