Topical Vancomycin Versus Standard Care in Diabetic CABG Patients: Effect on Sternal Wound Infection

Background: Although surgical practice and prophylaxis have improved still sternum wound infection is an expensive and severe problem of coronary artery bypass (CABG). Diabetic patients are, however, a very high-risk group of this complication because they have a weakened immunity and a slow healing of wounds. Although systemic antibiotic prophylaxis has remained very popular, its shortcomings have created interest in the usage of topical methods. The effectiveness of topical vancomycin powder in high-risk diabetic patients needs to be studied to generate local evidence. Objective: To determine the effectiveness of topical vancomycin application to the edges of the sternum in decreasing the sternal wound contamination rate in diabetic post-CABG patients. Methods: This quasi-experiment was done in a tertiary cardiac care institution. 100 eligible diabetic post-elective CABG patients were randomly assigned to two groups. The Vancomycin group (n = 50) received topical application of 1 gram of vancomycin powder on sternum while comparison group (n = 50) received standard care without the topical vancomycin. The incidence of sternal wound infection in 30 days was determined through the criteria of Jones. Data was entered on SPSS v23.0. Multivariate analysis was done. Results: Overall, the occurrence of sternal wound contamination was 8% in Vancomycin group and 26% in Control group with p=0.016 while Infection of deep sternal wound was present in 2% and 12% respectively. Vancomycin group had a significantly lesser median hospital stay associated to the comparison group, 7 and 8 days respectively (p=0.026). Topical vancomycin was found an independent protection on multivariate analysis with an adjusted odds ratio of 0.25 and 95% Confidence Interval [0.07-0.84, p=0.025). Conclusion: Topical vancomycin use is effective in preventing the occurrence of sternal wound infection as well as in the reduction of hospital stay in diabetic patients after CABG.