Risk Factors for Post-ERCP Pancreatitis in High-Risk Patients Receiving Post-procedure Rectal Indomethacin

Background Post-ERCP pancreatitis (PEP) is the most common adverse event of ERCP. Rectal indomethacin has been widely administered to decrease the incidence of PEP in high-risk patients. However, it cannot completely prevent the occurrence of PEP. The purpose of the study was to evaluate the risk factors for PEP in high-risk patients receiving post-ERCP indomethacin. Methods From June 2012 to July 2015, patients undergoing ERCP and at high risk for PEP in three tertiary hospitals in China were enrolled. All patients received indomethacin after the procedure. Patient-related and procedure-related risk factors for PEP were collected. Logistic regression analysis was used to investigate the risk factors. Results Seven hundred ninety patients at high risk for PEP received post-ERCP indomethacin. The incidence of overall PEP and moderate-to-severe PEP was 8.0 and 1.5%, respectively. In multivariate analysis, suspected sphincter of Oddi dysfunction (SOD) (OR 2.73; 95%CI 1.38-5.43; p=0.004), the presence of hilar obstruction (OR 4.53; 95%CI 1.60-12.81; p=0.004), number of cannulation attempts 13 (OR 2.00; 95%CI 1.07-3.77; p=0.030), inadvertent pancreatic duct (PD) cannulation 1 (OR 2.26; 95%CI 1.04-4.90; p=0.040), and pancreatic contrast injections 1 (OR 2.30; 95%CI 1.02-5.23; p=0.046) were high risk factors for overall PEP. For moderate-to-severe PEP, suspected SOD (OR 4.67; 1.19-18.35; p=0.027), the presence of hilar obstruction (OR 7.95; 1.39-44.97; p=0.010), and more cannulation attempts (OR 3.71; 1.09-12.65; p=0.036) were three independent risk factors. Conclusions A substantial number of high-risk patients had PEP even receiving post-ERCP rectal indomethacin. The independent risk factors included suspected SOD, hilar stricture, more cannulation attempts, inadvertent PD cannulation, and PD contrast injections.