Effect of Intrawound Vancomycin on Surgical Site Infections in Nonspinal Neurosurgical Procedures: A Systematic Review and Meta-Analysis

Background Applying vancomycin into the surgical site has been well-described in spinal neurosurgery, with extensive institutional experience and systematic reviews describing its effectiveness in reducing surgical site infections (SSIs). Its use in nonspinal neurosurgical procedures is a logical extension of those findings; however, recent studies have described varying degrees of success. We have summarized the effect of local vancomycin application on SSIs in nonspinal neurosurgical procedures and describe the quality of the supporting evidence. Methods MEDLINE, Embase, and Google Scholar were searched through June 2018. Information on study design, demographic data, exposure, and outcomes was extracted. The estimates were combined using random-effects models. Results Our search retrieved 9 studies for quantitative analysis. They assessed vancomycin use in craniotomy, cranioplasty, deep brain stimulator-related procedures, and ventriculoperitoneal shunt surgery. Most of the studies had serious methodological shortcomings that introduced confounding. We found an overall beneficial effect on SSI incidence (odds ratio, 0.25; 95% confidence interval, 0.12–0.52), which was seen across all subspecialties, except for cranioplasty. The use of vancomycin did not result in the emergence of resistant infections or in a significant increase in the proportion of infections caused by gram-negative organisms. Conclusions Vancomycin use in nonspinal neurosurgery is not supported by high-quality evidence, limiting the strength of the conclusions that can be drawn on the topic. Nonetheless, we found an overall favorable effect on SSIs (except in the context of cranioplasty), which should be reproduced in a randomized controlled fashion.