 Based on previous results, the investigators considered that sedation quality, complications, and procedure outcomes may not be different, however, propofol alone titration may have a fast recovery time than BPS and cost-effectiveness than balanced propofol sedation BPS. In present study, the investigators therefore evaluate the time and sedation quality of patient recovery, cost-effectiveness, complication, and procedure outcomes between propofol alone and BPS in therapeutic endoscopic retrograde cholangiopancreatography ERCP. 