Efficacy Study of Glyceryl-Trinitrate Patch and Parecoxib (Valdecoxib) for the Prevention of Pancreatitis After Endoscopic Retrograde Cholangiopancreatography (ERCP)

ERCP is a diagnostic and therapeutic procedure that is required in patients with suspected common bile duct stone, malignant biliary obstruction, biliary fistula, etc. Pancreatitis may occur as a complication of this procedure after about 5-10% of the ERCP procedures. This complication manifests as persisting pain 24 hours or more after ERCP, along with raised levels of pancreatic enzymes in the blood. Most of the cases of post-ERCP pancreatitis are mild, but may be severe and lead to prolonged hospitalization a few patients. The occurrence of this complication is unpredictable. There have been a number of attempts to prevent this complication. These include giving certain drugs before ERCP e.g. octreotide, somatostatin, steroids, etc. However, these have not been successful. Recently, a study showed that application of glyceryl trinitrate patch on the skin before ERCP might reduce the incidence of post ERCP-pancreatitis. Another study showed that per rectal administration of diclofenac tablet after the ERCP procedure also reduced occurrence of post ERCP pancreatitis. Other experimental studies have shown that certain anti-inflammatory drugs like cox-2 inhibitors may also be effective. The investigators want to study whether transdermal patch of glyceryl trinitrate or administration of injectable cox-2 inhibitor Valdecoxib (pro-drug Parecoxib) can prevent post-ERCP pancreatitis in our patients who undergo an ERCP.