Rectal indomethacin versus placebo to reduce the incidence of pancreatitis after endoscopic retrograde cholangiopancreatography: results of a controlled clinical trial

Background: Acute pancreatitis is the most common major complication after endoscopic retrograde cholangiopancreatography (ERCP). Many drugs have been evaluated for prophylaxis, including nonsteroidal anti-inflammatory drugs (NSAIDs), which are potent inhibitors of phospholipase A(2) and play a role in the pathogenesis of acute pancreatitis. Rectal NSAIDs have been shown in prospective studies to decrease the incidence of this complication, but the indication is not generalized in clinical practice. The aim of this study was to evaluate the efficacy of rectal administration of indomethacin in reducing the incidence of post-ERCP pancreatitis in high-risk patients. Methods: This was a controlled clinical trial where patients with an elevated risk of developing post-ERCP pancreatitis were assigned to receive 100 mg of rectal indomethacin or a 2.6 g suppository of glycerin immediately after ERCP, without placement of a pancreatic stent. The patients were determined to be at high risk based on validated patient-and procedure-related risk factors. Post-ERCP pancreatitis was defined as the presence of new upper abdominal pain, hyperamylasemia/hyperlipasemia (at least three times the upper limit) 2 hours after the procedure and hospitalization at least 48 hours because of the complication. Pancreatitis severity was defined according to Cotton's criteria. Results: One hundred sixty-six patients were included; 82 in the study group and 84 in the placebo group. Patients had at least one major and/or two minor risk factors for developing post-ERCP pancreatitis. The incidence of the complication was 4.87 % (4/82) in the study group and 20.23 % (17/84) in the placebo group; this difference was significant (P = 0.01). According to Cotton's criteria, 17 patients (80.9 %) developed mild pancreatitis and 4 (19.1 %) had moderate pancreatitis; 3 of these 4 patients belonged to the placebo group (P = 0.60). Based on these results, an absolute risk reduction of 0.15 (15 %), a relative risk reduction of 0.75 (75 %) and a number needed to treat of 6.5 patients were calculated to prevent an episode of post-ERCP pancreatitis. There was no mortality. Conclusions: Rectal indomethacin reduced the incidence of post-ERCP pancreatitis among patients at high risk of developing this complication.