Guideline-concordant antibiotic prophylaxis on surgical site infection rates following colorectal surgery: real-world data from Thailand

Purpose: Antibiotic prophylaxis (AP) is a key component in preventing surgical site infections (SSIs). The existing gap between clinical guidelines and real-world practice may influence SSI rates. This study aimed to compare SSI rates between patients receiving guideline-concordant AP based on the 2020 Thailand guideline (group A) and those receiving broader-spectrum and/or prolonged prophylaxis (group B).Methods: We reviewed a database of adult patients who underwent elective colorectal resection between January 2022 and April 2024 at the largest university hospital in Thailand. SSIs were diagnosed using the US Centers for Disease Control and Prevention’s criteria. SSI rates between the 2 groups were compared, and factors associated with SSIs were determined.Results: This study included 1,584 patients, with an average age of 66 years, and 822 (51.9%) were male. The most common operation was anterior resection (n=470, 29.7%). A total of 1,030 patients (65.0%) underwent open surgery, and 228 patients (14.4%) had stoma formation. There were 405 patients (25.6%) in group A. Overall, SSIs occurred in 104 patients (6.6%): 69 incisional SSIs (4.4%) and 35 organ/space SSIs (2.2%). There was no significant difference in SSI rates between groups (group A vs. group B: 4.7% [95% confidence interval (CI), 2.9%–7.2%] vs. 7.2% [95% CI, 5.8%–8.8%]; P=0.078). Multivariate analysis identified 3 independent predictors of SSIs: hypoalbuminemia (odds ratio [OR], 2.53; 95% CI, 1.54–4.16; P<0.001), obesity (OR, 1.89; 95% CI, 1.08–3.32; P=0.026), and intraoperative blood loss greater than 400 mL (OR, 1.83; 95% CI, 1.06–3.16; P=0.031).Conclusion: There was no significant difference in SSI rates following colorectal surgery between patients receiving guideline-concordant AP and those receiving broader-spectrum and/or prolonged prophylaxis.