A randomized parallel-group trial of propofol versus midazolam for sadation during ERCP

INTERVENTION: 1. Propofol group: a slow initial intravenous bolus of 0.8 mg/kg and maintain a continuous infusion of 3 mg/kg/h 2. Midazolam group: an initial bolus of 0.06mg/kg and inremental doses of 0.03mg/kg at the time of need CONDITION: Biliopancreatic disorder PRIMARY OUTCOME: sedation efficacy rate INCLUSION CRITERIA: 1. Patient over age 20 2. Patient who is clinically indicated for ERCP for examination or treatment of biliopancreatic disorder 3. Patient who has agreed to conditions after receiving an explanation about the contents of the present clinical study and who has signed the consent form