RELATIONSHIP BETWEEN TIMING OF SURGERY AFTER PREOPERATIVE BILIARY DRAINAGE AND OUTCOMES FOLLOWING PANCREATODUODENECTOMY

Abstract

ABSTRACT Background: The role and optimal timing of surgery following preoperative biliary drainage (PBD) in patients undergoing pancreatoduodenectomy remain controversial. Early surgery may be influenced by procedure-related inflammation, whereas delayed intervention may increase infectious complications due to biliary colonization. Objective: To evaluate the impact of the interval between biliary drainage and pancreatoduodenectomy on postoperative outcomes and its association with biliary contamination. Methods: This retrospective cohort study included 239 patients undergoing pancreatoduodenectomy between 2013 and 2025. Of these, 174 (73%) underwent PBD via endoscopic retrograde cholangiopancreatography. Patients were stratified by interval between drainage and surgery: ≤2 weeks, 3-6 weeks, and >6 weeks. The primary outcome was 90-day mortality; secondary outcomes included major complications (Clavien-Dindo ≥III). Multivariable logistic regression adjusted for confounders. Results: Surgery at 3-6 weeks was associated with the lowest rates of major complications (31.7%) and 90-day mortality (9.7%), compared with ≤2 weeks (57.1%; 28.6%) and >6 weeks (40.6%; 23.2%). Surgery outside this interval increased 90-day mortality risk (OR 2.9, 95%CI 1.07-7.83). Biliary colonization rose with longer intervals, exceeding 90% after three weeks. Conclusion: A 3-6 week interval between biliary drainage and pancreatoduodenectomy is associated with improved outcomes, suggesting an optimal window balancing inflammation and bacterial colonization.