Postoperative outcomes after receipt of ertapenem antimicrobial prophylaxis for colon surgery: a multicenter retrospective cohort study.

Objective: To evaluate postoperative outcomes among patients undergoing colon surgery who receive perioperative prophylaxis with ertapenem compared to other antibiotic regimens.

Design and setting: Multicenter retrospective cohort study among adults undergoing colon surgery in seven hospitals across three health systems from 1/1/2010 to 9/1/2015.

Methods: Generalized linear mixed logistic regression models were applied to assess differential odds of select outcomes among patients who received perioperative prophylaxis with ertapenem compared to other regimens. Postoperative outcomes of interest included surgical site infection (SSI), Clostridioides difficile infection (CDI) and clinical culture positivity for carbapenem-resistant Enterobacteraciae (CRE). Inverse probability weights were applied to account for differing covariate distributions across ertapenem and non-ertapenem groups.

Results: A total of 2,109 patients were included for analysis. The odds of postoperative SSI was 1.56 times higher among individuals who received ertapenem than among those receiving other perioperative antimicrobial prophylaxis regimens in our cohort (46 [3.5%] vs 20 [2.5%]; IPW-weighted OR 1.56, [95% CI, 1.08-2.26], P = .02). No statistically significant differences in odds of postoperative CDI (24 [1.8%] vs 16 [2.0%]; IPW-weighted OR 1.07 [95% CI, .68-1.68], P = .78) were observed between patients who received ertapenem prophylaxis compared to other regimens. Clinical CRE culture positivity was rare in both groups (.2%-.5%) and did not differ statistically.

Conclusions: Ertapenem use for perioperative prophylaxis was associated with increased odds of SSI among patients undergoing colon surgery in our study population, though no differences in CDI or clinical CRE culture positivity were identified. Further study and replication of these findings are needed.