A randomized trial of rectal indomethacin and sublingual nitrates to prevent post-ERCP pancreatitis

Acute pancreatitis is the most common adverse event of endoscopic retrograde cholangiopancreatography (ERCP). Recent data suggest that indomethacin can reduce the risk of post-ERCP pancreatitis (PEP) in high-risk individuals. However, whether the combination of indomethacin and sublingual nitrates is superior to indomethacin alone is unknown. Therefore, we aimed to evaluate the efficacy of rectally administered indomethacin plus sublingual nitrate compared with indomethacin alone to prevent PEP.

During a 17-month period, all eligible patients who underwent ERCP were enrolled in this study. We excluded patients who had undergone a prior endoscopic sphincterotomy. In a double-blind controlled randomized trial, patients received a suppository containing 100 mg of indomethacin, plus 5 mg of sublingual nitrate (group A), or a suppository containing 100 mg of indomethacin, plus sublingual placebo (group B), before ERCP. Serum amylase levels and clinically pertinent evaluations were measured in all patients after ERCP.

Of the 300 enrolled patients, 150 received indomethacin plus nitrate. Thirty-three patients developed pancreatitis: 10 (6.7%) in group A and 23 (15.3%) in group B (P=0.016, risk ratio=0.39, 95% confidence intervals (CI): 0.18-0.86). More than 80% of the patients were at high risk of developing pancreatitis after ERCP. Absolute risk reduction, relative risk reduction, and number needed to treat for the prevention of PEP were 8.6% (95% CI: 4.7-14.5), 56.2% (95% CI: 50.6-60.8), and 12 (95% CI: 7-22), respectively.

Combination of rectal indomethacin and sublingual nitrate given before ERCP was significantly more likely to reduce the incidence of PEP than indomethacin suppository alone. Multicenter trials to confirm these promising findings are needed.