The aim of this study is to compare sedation efficiency, safety and satisfaction by both endoscopist, assistants, and the patients between continuous infusion and intermittent bolus injection of propofol for deep sedation during ERCP.

The patients undergone ERCP were randomly assigned to either continuous infusion of propofol (continuous group) or midazolam plus intermittent bolus injection of propofol (intermittent group) for deep sedation. In the continuous group, propofol was continuously administered via infusion pump and the doses were determined by sedation assistants monitoring the patients. In the intermittent group, a loading dose of 2 mg of midazolam and 0.4 mg/kg of propofol was initially injected and repeated bolus injection of 20 mg of propofol was followed according to patients' sedation level. Sedation related parameters (total dose of propofol, induction/recovery time, patients' cooperation) and adverse events during the procedure were evaluated. Satisfaction scores by endoscopist, assistant, and patients and difficulty scores of maintaining the sedation by assistants were also graded after the procedure.

Inclusion Criteria:

• Patients undergone ERCP for biliary and pancreatic diseases

Exclusion Criteria:

• Comorbid conditions of ASA class 4-5
• Age under 18 years or over 90 years
• Pregnancy
• Past medication history of benzodiazepine or narcotics
• Known allergy to midazolam or propofol
• hypotension (systolic blood pressure <90 mmHg), hypoxemia (SaO2 <90%), or bradycardia (50/min) at baseline measurements