Intraoperative Bile Culture in Pancreaticoduodenectomy: Teaching Old Dogma New Tricks

Introduction: Biliary stents increase surgical site infections (SSIs) following pancreaticoduodenectomy due to bactibilia and contaminated intraoperative bile spillage. Intraoperative bile culture (IOBC) is performed to guide empiric therapy for SSIs; however, its utility is poorly studied. We sought to evaluate IOBC and the interplay between stenting, bactibilia, and SSI following pancreaticoduodenectomy. Methods: Patients undergoing pancreaticoduodenectomy from January 2008 to April 2020 were identified through our institutional National Surgical Quality Improvement Project (NSQIP) database; patients without IOBC were excluded. Odds of SSI were analyzed with multivariable logistic regression. Results: Four-hundred-eighty-three patients were identified. One-hundred-eighty-nine (39%) patients had plastic stents and 154 (32%) had metal stents. Three-hundred-twenty-nine (96%) patients with stents had bactibilia versus 18 (13%) without stents (P < 0.001). The biliary microbiome and antibiotic resistance patterns in patients with metal and plastic stents were nearly identical. Of 159 NSQIP-defined SSIs, most were incisional (n = 92, 58%). Bactibilia and stent presence were associated with incisional (OR 3.69 and 3.39, both P < 0.001) but not organ space SSI (P > 0.1); however, stent type was not (P > 0.5). Of the 73 speciated SSI cultures, an IOBC-identified organism was present in 42 (58%), while at least one organism not found in the IOBC was present in 49 (67%). Conclusion: Bactibilia is associated with incisional but not organ space SSI following pancreaticoduodenectomy and is strongly associated with stent presence. Stent type does not independently influence the biliary microbiome or SSI risk. IOBC has a poor ability to predict causative organisms in SSIs following pancreaticoduodenectomy and is not recommended for routine use.