Direct sternal administration of Vancomycin and Gentamicin during closure prevents wound infection

OBJECTIVES: Deep sternal wound infection is still a major complication in patients undergoing cardiac surgery. We previously identified mammary artery harvesting as a risk factor for decreased antibiotic tissue penetration. In addition, other risk factors including diabetes may inhibit sufficient tissue penetration of perioperative antibiotic prophylaxis. A novel closure protocol applying 2 topical antibiotics and further recommendations for sternal wiring was introduced at our department to decrease the incidence of sternal wound infections. METHODS: A 12-month period prior to (March 2013-February 2014) and after (July 2014-June 2015) the introduction of a novel sternal closure protocol was studied. All sternal wound infections resulting from an operation during this period were analysed. The closure protocol consisted of the intra-sternal application of vancomycin and the subcutaneous application of gentamicin. Furthermore, we increased the number of sternal wires for more uniform distribution of lateral forces. RESULTS: Patients in both groups were comparable regarding demographic data and risk factors. Fifty-three out of 919 patients operated prior to the protocol change developed an infection (5.8%). The introduction of the novel sternal closure protocol reduced this number to 19 out of 932 patients (2.0%; P < 0.001). A binary regression including common risk factors revealed a strong independent risk reduction by the novel protocol (OR 0.322, P < 0.001). The number of sternal wires was not significant in this analysis. CONCLUSIONS: The topical application of 2 antibiotic agents significantly reduced sternal wound infection. However, the results of this trial should be confirmed in a randomized trial.