S121 Predictors of Spontaneous Prophylactic Pancreatic Duct Stent Passage: The Role of Stent Size and Length

Introduction: Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis is one of the most common adverse events of ERCP. Prophylactic pancreatic duct (PD) stenting can decrease the incidence of post-ERCP pancreatitis but may require a repeat ERCP for stent removal if there is no spontaneous passage of the stent. Limited evidence exists on the impact of stent size on the likelihood of spontaneous stent passage. Our study aimed to evaluate and compare the rate of spontaneous passage of PD stents of varying sizes. Methods: This retrospective study included all patients who underwent ERCP between January 2014 and January 2024 at Geisinger Health System, a large tertiary center. Stents 4 cm or shorter were categorized as short stents, while stents 5 cm or longer were classified as long stents. The primary outcome was to compare the rate of spontaneous passage between short and long prophylactic PD stents. Secondary outcomes included identifying factors associated with spontaneous passage. Results: A total of 920 patients who underwent ERCP with PD stent placement were identified, of whom 149 (16.2%) had follow-up abdominal X-rays to assess stent passage. Among these 149 patients, 55% were women, 96% were White, and the mean age was 58.7 years. Spontaneous stent passage was seen in 115 (77.2%), while 34 (22.8%) stents were retained. The spontaneous stent passage rate was similar for both long stents and short stents (78.7% vs 66.7%; P = 0.18). In addition, there was no significant difference in subgroup analysis adjusted for stent diameter. However, the smaller diameter 4 Fr stents had a significantly higher rate of spontaneous passage compared to 5 Fr stents [85 (82.5%) vs 30 (65.2%); P = 0.02]. Conclusion: Our study demonstrates that smaller 4 Fr diameter stents have better rates of spontaneous stent passage; however, the stent length does not affect passage rates.