Supplementary Material for: Development of an Online App to Predict Post-Endoscopic Retrograde Cholangiopancreatography Adverse Events Using a Single-Center Retrospective Cohort

<b><i>Introduction:</i></b> Endoscopic retrograde cholangiopancreatography (ERCP) is a technically demanding procedure with a high risk for adverse events (AEs). <b><i>Aim:</i></b> evaluate patient- and procedure-related risk factors for ERCP-related AEs and develop an online app to estimate risk of AEs. <b><i>Methods:</i></b> retrospective study of 1,491 consecutive patients who underwent 1,991 ERCPs between 2012 and 2017 was conducted. AEs definition and severity were classified according to most recent ESGE guidelines. Each variable was tested for association with occurrence of overall AEs, post-ERCP pancreatitis (PEP) and cholangitis. For each outcome, 2 regression models were built, from which an online Shiny-based app was created. <b><i>Results:</i></b> Overall AE rate was 15.3%; in 19 procedures, &gt;1 AE occurred. Main post-ERCP AE was PEP (7.5%), followed by cholangitis (4.9%), bleeding (1.3%), perforation (1%), cardiopulmonary events (0.9%), and cholecystitis (0.3%). Seventy-eight percent of AEs were mild/moderate; of severe (<i>n</i> = 55) and fatal (<i>n</i> = 20) AEs, more than half were related to infection, cardiac/pulmonary AEs, and perforation. AE-related mortality rate was 1%. When testing precannulation, procedural covariates, and ERCP findings, AE occurrence was associated with age (odds ratio [OR] 0.991), previous PEP (OR 2.198), ERCP complexity grade III/IV (OR 1.924), standard bile duct cannulation (OR 0.501), sphincterotomy (OR 1.441), metal biliary stent placement (OR 2.014), periprocedural bleeding (OR 3.024), and biliary duct lithiasis (OR 0.673). <b><i>Conclusion:</i></b> Our app may allow an optimization of the patients’ care, by helping in the process of decision-making, not only regarding patient or endoscopist’s selection but also definition of an adequate and tailored surveillance plan after the procedure.