Objective. To evaluate the feasibility of implementation of the refined window for routine antimicrobial prophylaxis (RAP) of 30-74 minutes before skin incision compared to the World Health Organization (WHO) standard of 0-60 minutes. Design. Prospective study on timing of routine antimicrobial prophylaxis in 2 different time periods. Setting. Tertiary referral university hospital with 30,000 surgical procedures per year. Methods. In all consecutive vascular, visceral, and trauma procedures, the timing was prospectively recorded during a first time period of 2 years (A; baseline) and a second period of 1 year (B; after intervention). An intensive intervention program was initiated after baseline. The primary outcome parameter was timing; the secondary outcome parameter was surgical site infection (SSI) rate in the subgroup of patients undergoing cholecystectomy/colon resection. Results. During baseline time period A (3,836 procedures), RAP was administered 30-74 minutes before skin incision in 1,750 (41.0%) procedures; during time period B (1,537 procedures), it was administered in 914 (56.0%; P < .001). The subgroup analysis did not reveal a significant difference in SSI rate. Conclusions. This bundle of interventions resulted in a statistically significant improvement of timing of RAP even at a shortened window compared to the WHO standar
