Endoscopic retrograde cholangiopancreatography (ERCP) is an uncomfortable procedure that requires adequate sedation or general anesthesia for successful completion. For instance, over 48,000 procedures are carried out per annum in the UK alone [1–4]. We performed a prospective review of our hospital's ERCP records, to identify 660 subjects who required propofol. At our institution, propofol sedation for ERCP procedures is administered by anesthesiologists. The control group consisted of 330 patients that were not treated using anesthesia because of fear of anesthesia or because they were urgent cases.