Clinical significance of drain fluid culture after pancreaticoduodenectomy

Abstract

Background: The mechanism of infected postoperative pancreatic fistula (POPF) following pancreaticoduodenectomy (PD) is undefined. Drain amylase has been used to predict POPF, whereas little data are available about the value of drain fluid culture. The aim was to investigate the incidence, risk factors and association with surgical outcomes of positive drainage culture (PDC) after PD.

Methods: A single-center retrospective analysis was conducted of prospectively collected data from patients who underwent PD between January 2005 and December 2015. Drain fluid samples were obtained for microbiological analysis after surgery. Risk factors for PDC were evaluated, and its influence on surgical outcomes was explored.

Results: Of 768 patients, 261 (34%) had PDC during the postoperative period. Among them, a total of 434 isolates were yielded. One hundred and seven (24.7%) were Gram-positive, 283 (65.2%) Gram-negative, and 44 (10.1%) fungi. Multivariate analysis revealed that body mass index (BMI) ≥25 kg/m² , preoperative chemoradiation and intra-operative red blood cell transfusion were independent risk factors for PDC. PDC was associated with higher incidences of complications including POPF, major complications and reoperation, but with no correlation between the day of PDC and complications. BMI ≥25 kg/m² , early PDC (≤3 days), main pancreatic duct <3 mm, and soft pancreas were revealed as independent predictors for POPF. There was a correlation between type of microorganisms and complications.

Conclusion: Considering the correlation between PDC and postoperative complications, preventive measures are crucial to improve outcomes after PD. Whether antibiotic treatment for early PDC will alter the clinical course of POPF needs further evaluation.

Keywords: Bacterial contamination; Drainage culture; Pancreatic fistula; Pancreaticoduodenectomy; Postoperative complication.