Is the administration of vancomycin to operative field effective? Studying from operative wound drainage tube culture.

To investigate the efficacy of application of VCM powder to surgical wounds. A total of 314 patients who underwent posterior spinal instrumentation with local application of VCM (VCM group) were compared to 354 patients without VCM (control). The wound drainage tube was submitted for bacterial culture. The number of positive cultures, types of bacteria, and incidence of surgical site infections (SSI) were investigated. Drainage tube culture was positive in 1.6% (5/314 cases) and 7.3% (26/354 cases) of the VCM and control groups, respectively (P = 0.004). Among the five positive cases in the VCM group, one had an SSI, compared to three of 26 in the control group. Among the culture-negative cases, 0 and six, respectively, had an SSI. Finally, the incidence of SSI was 0.3% (1/314 cases) and 2.5% (9/354 cases), respectively. SSI occurred significantly less often in the VCM than in the control group (P = 0.01). The pathogenic bacterium was P. aeruginosa in the VCM group and MSSE, S. marcescens, methicillin-resistant S. aureus (MRSA), etc., in the control group. This study indicates that the amount of bacteria in the operative field was decreased by local application of VCM. However, the incidence of positive culture of VCM-resistant bacteria was not decreased by VCM. Importantly, pathogenic bacteria in the VCM group were only VCM-resistant, supporting the efficacy of VCM. In conclusion, local application of VCM decreases the amount of bacteria in the operative field and leads to fewer SSIs.