S1024 The Effect of Unintended Pancreatic Duct Cannulation on Post-ERCP Pancreatitis

Abstract

Introduction: Post-ERCP pancreatitis (PEP) is the most common adverse event of endoscopic retrograde cholangiopancreatography (ERCP). Numerous studies have identified multiple synergistic patient-based risk factors for PEP including suspected sphincter of Oddi dysfunction, prior PEP, female gender, younger age, normal serum bilirubin, and history of acute recurrent pancreatitis. However, unintended pancreatic duct (PD) cannulation is less well studied as a risk factor for PEP. Our study investigates the risk of PEP in unintended PD cannulation. Methods: We conducted a retrospective cohort study of all ERCPs by a single advanced endoscopist between December 2013 and January 2020 at a tertiary medical center. Patients with prior sphincterotomy were considered to have a non-native papilla and were excluded. Details of the ERCP, laboratory results, hospitalizations, clinic visits, and follow-up phone calls were identified via chart review. PEP was defined by the revised Atlanta classification. Multiple logistic regression analysis was used to model demographic and clinical features of those who did and did not develop PEP. Group differences for various factors were compared using odds ratios calculated via Fisher’s exact test. Results: 823 ERCPs were included in this analysis of which 3.77% were complicated by PEP. The incidence of PEP was 8.4% among unintended PD cannulation, 3.2% among intentional PD cannulation, and 1.5% among no PD cannulation (Fisher's exact p-value < 0.00005). Using multiple logistic regression, PEP positively correlated with unintended PD cannulation (p-value < 0.005) but not intended PD cannulation. When controlled for age and gender, needle knife sphincterotomy was also identified as a risk factor for PEP (p-value = 0.017). Additionally, age was negatively correlated with PEP in unintended PD cannulation (p-value = 0.027). In both unintended and intended PD cannulation, PEP rates were not affected by contrast injection into the PD compared with just guidewire cannulation without contrast injection. Conclusion: While unintended PD cannulation appears to increase the likelihood of PEP, intentional cannulation does not seem to have the same effect, suggesting that underlying pancreatic disease such as chronic pancreatitis or pancreatic trauma confers a lower risk of PEP. Further studies are needed to determine whether patients with unintended PD cannulation could benefit from more aggressive PEP prophylaxis or monitoring after ERCP.