Perioperative Infection Prophylaxis With Vancomycin is a Significant Risk Factor for Deep Surgical Site Infection in Spine Surgery

Study Design.Retrospective cohort. Objective.The purpose of this study was to compare the efficacy of cefazolin versus vancomycin for perioperative infection prophylaxis. Summary of Background Data.The relative efficacy of cefazolin alternatives for perioperative infection prophylaxis is poorly understood. Materials and Methods.This study was a single-center multisurgeon retrospective review of all patients undergoing primary spine surgery from an institutional registry. Postoperative infection was defined by the combination of three criteria: irrigation and debridement within 3 months of the index procedure, clinical suspicion for infection, and positive intraoperative cultures. Microbiology records for all infections were reviewed to assess the infectious organism and organism susceptibilities. Univariate and multivariate analyses were performed. Results.A total of 10,122 patients met inclusion criteria. The overall incidence of infection was 0.78%, with an incidence of 0.73% in patients who received cefazolin and 2.03% in patients who received vancomycin (OR: 2.83, 95% CI: 1.35-5.91, P=0.004). Use of IV vancomycin (OR: 2.83, 95% CI: 1.35-5.91, P=0.006), BMI (MD: 1.56, 95% CI: 0.32-2.79, P=0.014), presence of a fusion (OR: 1.62, 95% CI: 1.04-2.52, P=0.033), and operative time (MD: 42.04, 95% CI: 16.88-67.21, P=0.001) were significant risk factors in the univariate analysis. In the multivariate analysis, only noncefazolin antibiotics (OR: 2.48, 95% CI: 1.18-5.22, P=0.017) and BMI (MD: 1.56, 95% CI: 0.32-2.79, P=0.026) remained significant independent risk factors. Neither IV antibiotic regimen nor topical vancomycin significantly impacted Gram type, organism type, or antibiotic resistance (P>0.05). The most common reason for antibiosis with vancomycin was a penicillin allergy (75.0%). Conclusions.Prophylactic antibiosis with IV vancomycin leads to a 2.5 times higher risk of infection compared with IV cefazolin in primary spine surgery. We recommend the routine use of IV cefazolin for infection prophylaxis, and caution against the elective use of alternative regimens like IV vancomycin unless clinically warranted.