Preoperative biliary stenting is associated with increased bacterial contamination and postoperative inflammation in pancreatic head resections

BACKGROUND: The role of preoperative biliary drainage (PBD) in patients with resectable pancreatic head cancer remains controversial. Although traditionally used to reduce hyperbilirubinemia, increasing evidence suggests an association with higher postoperative morbidity. This study evaluated the impact of preoperative biliary stenting on microbial contamination, postoperative inflammatory response, and clinical outcomes. METHODS: This retrospective single-center study included 102 patients with preoperative cholestasis and hyperbilirubinemia who underwent pancreatic head resection between March 2017 and January 2024. Patients were divided into a stent group (n = 66) and a no-stent group (n = 36). Intraoperative bile cultures, perioperative parameters, postoperative complications, and serial laboratory values were analyzed. RESULTS: Patients who underwent preoperative stenting showed significantly higher rates of positive intraoperative bile cultures (75.8% vs. 5.6%, p < 0.001), longer operative times (360.4 vs. 319.8 min, p = 0.038), and prolonged time to surgery (51.2 vs. 23.8 days, p = 0.001). Among culture-positive patients, contamination was predominantly polymicrobial (80.8%, 140 isolates in total), with Enterobacterales (43.6%) and Enterococcus species (35.7%) as the most frequent isolates and Candida species detected in 19.2% of these patients. Postoperative CRP levels were significantly higher in the stent group on postoperative days 3 and 5. Abdominal wound dehiscence occurred exclusively in stented patients (12.1% vs. 0%, p = 0.048). Rates of other complications, ICU stay, and hospital length of stay were comparable between groups. CONCLUSION: Preoperative biliary stenting is associated with predominantly polymicrobial bacterial bile contamination, longer operative times, increased postoperative inflammatory response and wound-related complications, while pancreas-specific complications were not significantly increased. These findings support a selective rather than routine use of biliary drainage in patients with resectable pancreatic cancer, and suggest that the microbial spectrum, including the detection of Candida species in nearly one fifth of culture-positive patients, should be considered when planning perioperative antimicrobial strategies.