Ensuring appropriate timing of antimicrobial prophylaxis.

Background: Delivery of intravenous antibiotic prophylaxis within one hour prior to surgical incision is considered important in helping to decrease the incidence of surgical site infections, but methods to ensure compliance have not been established.

Methods: All patients at our institution are subjected to a surgical "time-out" protocol to prevent wrong-site surgery. During a seven-week period, all patients undergoing spine surgery, total hip arthroplasty, or total knee arthroplasty had another safety initiative, that of ensuring that prophylactic intravenous antibiotics were administered at least one hour prior to incision, "piggybacked" onto our existing time-out verification checklist. In addition, we compared compliance during the study period with compliance during a three-month period prior to institution of this protocol and compliance for eighteen months after institution of this protocol.

Results: The average time (and standard deviation) between the antibiotic administration and the incision was 26 +/- 12 minutes for all patients. The protocol was effective in ensuring antibiotic administration at the optimal time to 316 (99.1%) of the 319 patients. Analysis of a group of forty patients who had undergone total hip or knee replacement during the three months prior to the beginning of the study demonstrated a compliance rate of 65%. The difference between this baseline compliance rate and the rate during the study period was significant (p < 0.0001). The compliance rate was 97% for 160 patients who underwent similar procedures during the eighteen months after completion of the study. Independent audits demonstrated continuation of the significantly better compliance with timing of antibiotic prophylaxis for patients undergoing total hip and knee arthroplasty since the implementation of the protocol in our institution.

Conclusions: Piggybacking of verification of prophylactic antibiotic administration onto the wrong-site-surgery time-out protocol is an effective, cost-free, and easy-to-adopt method to ensure compliance with appropriate timing of prophylactic antibiotics.