Prospective randomized double-blind placebo-controlled trial of glyceryl trinitrate in endoscopic retrograde cholangiopancreatography-induced pancreatitis

Background: One possible aetiology of pancreatitis following endoscopic ret rograde cholangiopancreatography (ERCP) is cannulation-induced spasm of the sphincter of Oddi and consequent pancreatic duct obstruction. Sublingual g lyceryl trinitrate (GTN) has been shown to produce periampullary sphincter relaxation. The aim of this study was to determine whether prophylactic lon g-acting GTN could reduce the incidence of ERCP-induced pancreatitis. Methods: In a randomized double-blind study, prophylactic treatment with GT N (2 mg given sublingually 5 min before endoscopy) was compared with placeb o in 186 patients who presented for elective ERCP. The primary endpoint was the occurrence of pancreatitis within 24 h, defined as a serum amylase con centration greater than 1000 units/ml in association with a visual analogue pain score of more than 5. Results: The incidence of pancreatitis was lower in the GTN group compared with placebo (seven of 90 versus 17 of 96; P < 0.05). Mean serum amylase va lues were similar in the two groups. The protective effect of GTN appears t o be highest in the diagnostic ERCP group (one of 54 versus ten of 66; P = 0.012) and in the group in which cholangiography alone was performed (one o f 54 versus eight of 57; P = 0.032). Conclusion: Prophylactic treatment with GTN reduces the incidence of pancre atitis following ERCP but does not seem to reduce the extent of hyperamylas aemia or the severity of pancreatitis.