Intraoperative redosing of antibiotics for prevention of surgical site infections: A systematic review and meta-analysis

Background: Appropriate antibiotic prophylaxis is essential for preventing surgical site infections (SSI); however, the clinical benefit of intraoperative redosing remains unclear and controversial owing to insufficient reliable evidence. Therefore, we performed a systematic review and meta-analysis to assess the effectiveness of prophylactic antibiotic redosing in lengthy surgical procedures. Methods: We systematically searched the PubMed, Cochrane Library, Web of Science, and Ichushi-Web databases for articles published until 31 December, 2023. We compared the incidence of SSI between patients receiving and not receiving intraoperative redosing of antibiotics in surgeries lasting ≥3 h. Subgroup analyses were conducted across study characteristics. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using the Mantel–Haenszel random effects model. The risk of bias was assessed using the ROBINS-I. Results: Overall, seven observational studies involving 4,671 patients were included. Intraoperative antibiotic redosing significantly reduced the risk of SSI compared with non-redosing (OR = 0.65, 95% CI = 0.45–0.94, p = 0.02). Subgroup analyses showed that intraoperative redosing decreased SSI risk in studies with a minimum 4-h operative time, no postoperative antibiotic continuation, and a moderate risk of bias. However, the statistical heterogeneity of the analyses was high among the studies. Conclusions: Intraoperative redosing with prophylactic antibiotics during lengthy surgeries may be associated with a lower risk of SSI than non-redosing. Therefore, we recommend intraoperative redosing for surgeries lasting beyond 3–4 h to reduce the risk of infection. Further research is required to clarify the optimal redosing interval, which should be prioritized in future studies.