Rectal Indomethacin With or Without Papillary Ice Water Irrigation to Prevent Post-ERCP Pancreatitis

Post-endoscopic retrograde cholangiopancreatography pancreatitis (post-ERCP pancreatitis, or PEP) is inflammation of the pancreas that can occur after an ERCP procedure. Rectal indomethacin is commonly given around the time of ERCP to help reduce this risk, but pancreatitis can still occur despite this treatment. The purpose of this randomized clinical trial is to determine whether adding ice water irrigation of the papilla at the end of ERCP further reduces the risk of post-ERCP pancreatitis compared with rectal indomethacin alone. The papilla is the small opening in the intestine where the bile duct and pancreatic duct drain. Participants will be randomly assigned to one of two groups. Both groups will receive rectal indomethacin 100 mg. In the intervention group, the doctor will also irrigate the papilla with a total of 250 mL of ice water immediately after the ERCP. Participants and the study team members who assess study outcomes will not know which treatment group the participant was assigned to. Participants will be assessed after ERCP and followed for up to 30 days for pancreatitis and other complications.

Inclusion Criteria: * Age 18 years or older. * Undergoing ERCP with a native papilla. * Eligible to receive rectal indomethacin. * Able to provide informed consent. * Willing and able to complete the required follow-up and post-procedure bloodwork. Exclusion Criteria: * Known allergy, hypersensitivity, or contraindication to indomethacin or rectal NSAIDs. * Active acute pancreatitis at the time of ERCP. * Prior sphincterotomy or absent native papilla. * Prediction of papilla inaccessibility. * Pregnancy. * Inability or unwillingness to provide informed consent. * Any clinical circumstance in which the treating endoscopist judges study participation to be unsafe or inappropriate. * Chronic pancreatitis. * Pancreatic head malignancy with complete main pancreatic duct obstruction. * Altered luminal anatomy, other than Billroth I.