Impact of Antibiotic Prophylaxis Duration on the Incidence of Healthcare-Associated Infections in Elective Colorectal Surgery

<b>Background/Objectives</b>: Antibiotic prophylaxis is a key component of infection prevention strategies. This study aimed to evaluate whether the duration of antibiotic prophylaxis influences the incidence of HAIs in patients undergoing elective colorectal surgery. <b>Methods</b>: This prospective cohort study included 278 adult patients who underwent elective colorectal surgery at a single tertiary care center. Patients were categorized into two groups based on the duration of antibiotic prophylaxis: one day or more than one day. Data on demographics, clinical characteristics, perioperative variables, and infection outcomes were collected. <b>Results</b>: The overall incidence of HAIs was 16.9%, with no significant difference between patients receiving one-day versus extended antibiotic prophylaxis. However, traditional multivariate analysis showed that prophylaxis lasting more than one day was independently associated with a significantly lower risk of HAI (RR = 0.30, 95% CI: 0.12-0.75, <i>p</i> = 0.010) and surgical site infections (RR = 0.24, 95% CI: 0.08-0.72, <i>p</i> = 0.011). After adjusting for confounders using propensity score matching, this association was no longer statistically significant. No significant association was found between prophylaxis duration and urinary tract infections. Regarding antibiotic selection, first-generation cephalosporins were the most commonly used agents, accounting for 78.8% of prophylactic prescriptions. This was followed by fluoroquinolones (14.4%) and third-generation cephalosporins (5.0%). All patients received metronidazole, a nitroimidazole-class antimicrobial, in combination with the above agents. <b>Conclusions</b>: One day of prophylactic antibiotics may be sufficient in SSI prevention in patients undergoing elective colorectal surgery. The use of extended antibiotic prophylaxis beyond one day should be considered for high-risk patients at high risk of infection, particularly those requiring ICU care.