New classification system for indications for endoscopic retrograde cholangiopancreatography predicts diagnoses and adverse events

Background: Indications for endoscopic retrograde cholangiopancreatography (ERCP) have received little attention, especially in scientific or objective terms. Aim: To review the prevailing ERCP indications in the literature, and to propose and evaluate a new ERCP indication system, which relies on more objective pre-procedure parameters. Methods: An analysis was conducted on 1758 consecutive ERCP procedures, in which contemporaneous use was made of an a-priori indication system. Indications were based on the objective pre-procedure parameters and divided into primary [cholangitis, clinical evidence of biliary leak, acute (biliary) pancreatitis, abnormal intraoperative cholangiogram (IOC), or change/removal of stent for benign/malignant disease] and secondary [combination of two or three of: pain attributable to biliary disease (‘P’), imaging evidence of biliary disease (‘I’), and abnormal liver function tests (LFTs) (‘L’)]. A secondary indication was only used if a primary indication was not present. The relationship between this newly developed classification system and ERCP findings and adverse events was examined. Results: The indications of cholangitis and positive IOC were predictive of choledocholithiasis at ERCP (101/154 and 74/141 procedures, respectively). With respect to secondary indications, only if all three of ‘P’, ‘I’, and ‘L’ were present there was a statistically significant association with choledocholithiasis (χ²(1) = 35.3, p <.001). Adverse events were associated with an unusual indication leading to greater risk of unplanned hospitalization (χ²(1) = 17.0, p <.001). Conclusions: An a-priori-based indication system for ERCP, which relies on pre-ERCP objective parameters, provides a more useful and scientific classification system than is available currently.