[Utility of topical vancomycin application in the prevention of surgical site infection of the lumbosacral spine].

Introduction: surgical site infections (SSI) remain a significant cause of morbidity and mortality and one of the most representative causes of nosocomial infections. The use of intrawound vancomycin in lumbar spine surgery is a potential prophylactic measure against SSI; however, evidence regarding its efficacy is contradictory. Our study was designed to research if intrawound vancomycin significantly prevents SSI in lumbar spine surgery.

Material and methods: this is a randomized, double-blinded, controlled clinical trial; 233 patients who underwent lumbar spine surgery, were randomly assigned to a group in which intrawound vancomycin was instilled in the incision before closure (109), or to a control group (114). The main outcome is the presence of SSI; we determined its prevalence and searched for difference between groups for association between SSI and independent variables.

Results: global SSI prevalence was 1.8%, in the experimental group was 0.9%, in the control group was 2.6%. There was no significant difference between these values, p = 0.622. The relative risk of SSI in the experimental group was 0.35 (95% CI 0.037-3.30), that of the control group was 2.87 (95% CI 0.30-27.16). The number needed to treat is 58.3. We did not find a significant association between the independent variables studied and the appearance of SSI.

Conclusions: we did not find a significant difference in the prevalence of SSI between groups nor a significant association between SSI and independent variables.