The Effect of Topical Vancomycin Treatment against Sternal Wound Infection in Patients Undergoing Coronary Artery Bypass Graft Surgery

Objectives: Sternal wound infection (SWI) is one of the major complication following coronary artery bypass graft (CABG) surgery. The aim of this study was to investigate the protective effect of topical vancomycin treatment against SWI in patients (pts) undergoing on- and off-pump CABG.

Methods: All pts, who received on- and off-pump CABG between January 2015 and December 2017 at our institution were enrolled in this retrospective study. In October 2016, we initiated topical application of vancomycin to prevent SWI. Pts were divided into two groups: the vancomycin group (Gr. 1) received vancomycin and the control group (Gr. 2) received no topical treatment.

Pts characteristics, intraoperative data and early postoperative mortality, morbidity, and especially the incidence of SWI were compared between the groups.

Results: Out of 1,471 pts undergoing CABG vancomycin was topically applied in 602 pts (41%). Pts cohorts did not differ in age (Gr. 1: 67 ± 8 vs. 67 ± 10 years; p = 0.219) and body mass index (Gr. 1: 27 ± 5 vs. 28 ± 4 kg/m²; p = 0.180). Number of pts with diabetes (Gr. 1: 29 vs. 26.4%; p = 0.276) and re-do surgeries (Gr. 1: 1.7 vs. 1.3%; p = 0.654) were also similar. Preoperative creatinine (Gr. 1: 1.5 ± 0.4 vs. 1.8 ± 0.6 mg/dL; p = 0.198) and need for renal replacement therapy (Gr. 1: 1 vs. 1.2%; p = 0.114) were also comparable. The rate of female pts was significantly higher in Gr. 2 (20 vs. 15%; p = 0.019). Pts from in Gr. 1 received less likely an off-pump CABG (27 vs. 40%; p = 0.037) and bilateral internal thoracic arteries bypass grafting (58 vs. 67%; p = 0.024). No difference were detected in total number of grafts (Gr. 1: 2.4 ± 0.8 vs. 2.5 ± 0.9; p = 0.896) and in mean duration of operation (Gr. 1: 208 ± 145 vs. 212 ± 161 minutes; p = 0.742). In-hospital mortality (Gr. 1: 0.9 vs. 1.2%; p = 0.309) and in-hospital stay (Gr. 1: 7.9 ± 5.9 vs. 8.4 ± 4.7 days; p = 0.587) were also comparable in both groups.

Mean onset of SWI was at 67 ± 42 postoperative day without differences between the groups. There was a trend to a lower incidence of SWI in the vancomycin group (1.4 vs. 2.6%, p = 0.081). However, the incidence of deep SWI was significantly lower in this cohort (0.5 vs. 1.9%; p = 0.024). No difference was detected in mean time of infection treatment (35 ± 22 vs. 33 ± 29 days; p = 0.574), and two pts. died during this period.

Conclusion: Locally applied vancomycin reduced the incidence particularly of deep sternum wound infection in CABG patients.

No conflict of interest has been declared by the author(s).