Glyceryl trinitrate for prevention of pancreatitis after endoscopic retrograde cholangiopancreatography: a meta-analysis of randomized, double-blind, placebo-controlled trials

Background and study alms: Although trials evaluating the preventive effect of glyceryl trinitrate (GTN; nitroglycerin) on pancreatitis occurring after endoscopic retrograde cholangiopancreatography (ERCP) have been reported, there is no agreement as to whether prophylactic GTN treatment can in fact reduce the incidence of post-ERCP pancreatitis. We performed a meta-analysis to compare the effects of prophylactic GTN with placebo on post-ERCP pancreatitis. Study design: Databases including PubMed, EM-BASE, the Cochrane Library, and the Science Citation Index were searched to find relevant randomized controlled trials (RCTs). Two reviewers independently identified relevant trials evaluating the prophylactic effect of GTN on the occurrence of post-ERCP pancreatitis. The outcome measure was the incidence of post-ERCP pancreatitis. Results: Eight trials involving 1920 patients were analyzed. Meta-analysis showed that the incidence of post-ERCP pancreatitis was significantly reduced by GTN treatment (GTN group 5.9%, placebo group 9.8%, P = 0.002), with a relative risk of 0.61 (95% confidence interval 0.44-0.84). Patients who received GTN were 39% less likely to develop pancreatitis. Subgroup analyses suggested that GTN administered by the sublingual or transdermal route may be useful. Conclusions: Prophylactic GTN is useful for prevention of post-ERCP pancreatitis, but the optimal dosage and the optimal route and timing of administration need further clarification before this treatment can come into routine clinical use.