Interrupted time series analysis of the impact of a bundle on surgical site infections after colon surgery

Background Surgical site infections (SSIs) are monitored in Italy through a national surveillance system. A 4-element bundle was introduced 2012, consisting of: appropriate preoperative shower and hair removal, perioperative normothermia, antibiotic prophylaxis. The aim of this study to evaluate the effect intervention on SSI rates after colon surgery. Methods retrospective cohort conducted between 2008 2019 29 hospitals northern Italy. An interrupted time series analysis (ITSA) modeled assess bundle's impact trends. Logistic regression performed identify predictors among procedures postintervention period, comparing full partial compliance. Results Data 5487 surgery were collected (1243 preintervention 4244 postintervention). ITSA identified significant change monthly trend −0.19% level −2.09%. protective compliance compared (OR 0.74, P.043) found, whereas single elements nonsignificant. Conclusions Results suggest relatively simple protocol is effective reducing risk.