The Role of Pancreatic Duct Stenting in the Prevention of Post-ERCP Pancreatitis in the Setting of Rectal Indomethacin Usage

Abstract

Introduction: Rectal indomethacin has been demonstrated to reduce post-ERCP pancreatitis (PEP) in high-risk patients. Pancreatic duct stents (PDS) were also shown to reduce PEP in these patients. PDS have drawbacks and some endoscopists defer PDS placement due to a lack of technical expertise. The vast majority of studies of the effect of PDS placement were performed in patients who did not receive indomethacin. Thus, the role of PDS is unclear with concomitant administration of indomethacin. Methods: Our single-center retrospective cohort study evaluated 880 high-risk patients undergoing ERCP at the Hospital of the University of Pennsylvania between 2008 and 2015. Patients were determined to be at high risk on the basis of validated risk factors. After June 2012, with few exceptions, patients received indomethacin following ERCP. We collected data on demographic and clinical features, procedures, and development of PEP. PEP was defined by consensus criteria. Multivariable logistic regression was used to determine the association between indomethacin, PDS, and the primary outcome. Results: There were 384 patients in the indomethacin-exposed cohort and 496 patients in the unexposed cohort. 131 exposed patients had a PDS placed (31 with immediate removal and 100 left in place) compared to 89 patients in the unexposed cohort (14 with immediate removal and 75 left in place). (Figure 1) Adjusted for risk factors in the unexposed cohort, PDS with planned removal reduced the risk of PEP by 68% (OR 0.32 95% CI 0.11-0.93, p=0.04) while immediate removal of PDS increased the risk of PEP (OR 3.14 95% CI 1.03-9.52, p=0.04). Indomethacin reduced PEP by 81% (OR 0.19 95% CI 0.09-0.42 p < 0.001) compared to unexposed patients. Concomitant PDS with immediate removal mitigated this beneficial effect (OR 0.44 CI 0.10-1.93, p=0.28) while PDS left in did not significantly affect the benefit of indomethacin (OR 0.34 95% CI 0.13-0.89, p=0.02).Figure 1Conclusion: Our retrospective cohort study inclusive of high-risk patients at risk for PEP demonstrated: 1. In patients who did not receive indomethacin, PDS left in significantly reduced the risk of PEP. 2. In patients who received indomethacin but no stent there was a significantly reduced risk of PEP. 3. In patients who received PDS and indomethacin the immediate removal of PDS significantly increased the risk of PEP and mitigated the beneficial effect of indomethacin while stents left in did not significantly change the effect of indomethacin.