Rectal NSAIDs With/Without PD Stent for PEP Prevention

Inclusion Criteria: * 18-90 years old patients with native papilla who planned to undergo ERCP * high-risk patients for post-ERCP pancreatitis must meet one or more following criteria: clinical suspicion of sphincter of Oddi dysfunction, a history of PEP, pancreatic sphincterotomy, precut sphincterotomy, difficult cannulation (\>5 cannulation attempts, or \>5mins cannulation time, or \>1 unintentional pancreatic duct cannulation), or ballon dilatation of an intact biliary sphincter ≤ 1 min, double-wire cannulation. Additionally, patients were considered high-risk if they fulfilled two or more of the following minor criteria: female gender under 50 years old, a history of recurrent pancreatitis (two or more episodes), three or more contrast injections into the pancreatic duct with at least one injection reaching the tail of the pancreas, opacification of pancreatic acini, or brush cytology performed on the pancreatic duct. Exclusion Criteria: * Previous biliary sphincterotomy and papillary large balloon dilation * Planned for placements of pancreatic duct stents (eg. pancreatic duct strictures, planned ampullectomy) * Allergy to NSAIDs * The administration of NSAIDs within 7 days * Not suitable for NSAIDs administration (gastrointestinal hemorrhage within 4 weeks, renal dysfunction \[Cr \>1.4mg/dl=120umol/l\]; presence of coagulopathy before the procedure) * Acute pancreatitis within 7 days before ERCP or acute pancreatitis with obvious Pancreatic edema and peripancreatic fluid collections * Hemodynamical instability * Pregnancy or lactation * high-risk patients with pancreatic duct wire passages