Extended antibiotic prophylaxis after pancreatoduodenectomy reduces postoperative abdominal infection in high-risk patients: Results from a retrospective cohort study.

Background: Preoperative biliary stenting before pancreatoduodenectomy is associated with a greater risk of bacteribilia and thus could lead to more frequent and severe surgical site infections. We hypothesized that an extended antibiotic prophylaxis could reduce the risk of surgical site infections for these high-risk patients compared with standard antibiotic prophylaxis.

Methods: All consecutive patients who underwent pancreatoduodenectomy between January 1, 2010 and December 31, 2016 were included in a tricentric retrospective cohort and classified according to the risk of surgical site infections (high or low) and the type of antibiotic prophylaxis (standard or extended). Extended antibiotic prophylaxis was defined by the use of high-rank β-lactams >2 days after surgery. Standard antibiotic prophylaxis concerned all single dose of low-rank β-lactams antibiotic prophylaxis. The primary outcome was postoperative surgical site infections.

Results: Three hundred and eight patients were included; 146 (47%) were high-risk patients, and 81 (55%) received extended antibiotic prophylaxis, mostly composed of piperacilline-tazobactam and gentamicin. There were significantly fewer surgical site infections in high-risk patients receiving extended antibiotic prophylaxis versus standard antibiotic prophylaxis (odds ratio = 0.4; 95% confidence interval, 0.2-0.8; P = .011), even after adjusting on age, sex, and duration of the surgical procedure (adjusted odds ratio = 0.3; 95% confidence interval, 0.1-0.7; P = .0071). There was no statistical difference in 28-day mortality (P = .32) or 90-day mortality (P = .13). Microorganisms identified in bile culture were more often sensitive to antibiotic prophylaxis in high-risk extended antibiotic prophylaxis group than in high-risk standard antibiotic prophylaxis group (64% versus 38%; P = .01).

Conclusion: Extended antibiotic prophylaxis is associated with a reduced risk of surgical site infections for high-risk patients with no significant reduction on 28-day mortality. Additional studies are required to determine the optimal duration of extended antibiotic prophylaxis for these patients.