# Prolonged Prophylactic Antibiotics Based on Preoperative Bile Culture Reduce Surgical Site Infections After Pancreaticoduodenectomy Following Preoperative Biliary Drainage: A Propensity‐Matched Analysis

## TL;DR

Extending antibiotic use after a specific surgery lowers infection risk in patients who had pre-surgery bile drainage.

## Contribution

Prolonged prophylactic antibiotics reduce surgical site infections after pancreaticoduodenectomy following biliary drainage.

## Key findings

- Prolonged antibiotics reduced surgical site infections from 29% to 13%.
- Elevated postoperative amylase and short antibiotic duration were independent infection risk factors.
- Propensity-matched analysis confirmed the benefit of prolonged antibiotic use.

## Abstract

The optimum duration of prophylactic antibiotics after pancreaticoduodenectomy following preoperative biliary drainage to prevent surgical site infections remains controversial. We evaluate whether a prolonged course of prophylactic antibiotics reduces surgical site infection after pancreaticoduodenectomy following biliary drainage more than that within the standard duration.

We enrolled 352 consecutive patients from one hospital who underwent pancreaticoduodenectomy following biliary drainage between 2010 and 2023. The patients were prospectively assigned to two groups according to prophylactic antibiotic duration. In the standard duration group (2010–2013; 112 patients), the duration was within 24 h postoperatively. In the prolonged duration group (2014–2023; 240 patients), it was 3 days postoperatively. The primary endpoint was the incidence of surgical site infection between these groups. We performed 1:1 propensity score matching to balance baseline characteristics, which yielded 77 patients per group.

There was significantly less surgical site infection in the longer duration group (13%) than in the standard duration group (29%) (p = 0.0010). After matching, the prolonged duration group maintained significantly lower rates of all surgical site infection (32% vs. 14%, p = 0.0126), organ/space surgical site infection (27% vs. 13%, p = 0.0433), incisional surgical site infection (18% vs. 3%, p = 0.0026), superficial incisional surgical site infection (13% vs. 3%, p = 0.0314). In the multivariate analysis, independent risk factors for surgical site infection after pancreaticoduodenectomy following biliary drainage were elevated drain fluid amylase on postoperative day 1 (p < 0.0001) and 1‐day prophylactic antibiotics (p = 0.00012).

Prolonged prophylactic antibiotics significantly reduced surgical site infection incidence after pancreaticoduodenectomy in patients undergoing preoperative biliary drainage.