Negligible Systemic Uptake of Suprafascial Vancomycin Powder Following Instrumented Posterior Spinal Fusion-Preliminary Results From A Randomized Clinical Trial (VANCO Trial)

BACKGROUND: Intrawound vancomycin powder is an emerging strategy to reduce surgical site infections (SSls) in spine surgery. However, there are concerns relating to its safety profile and toxicity. Data on systemic uptake of suprafascially administered vancomycin powder following instrumented spinal fusion is lacking. OBJECTIVE: To study the systemic uptake and safety of suprafascially administered vancomycin powder in the early postoperative phase following open instrumented posterior spinal fusion. METHODS: This was a substudy of an ongoing randomized clinical trial. Eligible adult patients were randomized 1:1 to either receive suprafascial vancomycin powder before wound closure or not to receive vancomycin powder. Serum vancomycin levels were assessed on postoperative days 1 and 2, serum creatinine levels were measured pre-and post-operatively. Adverse events up to 6 wk following surgery were recorded. RESULTS: Among 34 randomized patients (mean age 62 yr, range 31-84 yr; 18 [53%] women), 17 received vancomycin powder. No detectable serum vancomycin levels (>4.0 mg/L) were found. Proportion of adverse events per patient in the vancomycin and control group, respectively, were 29.4 0 /0 (5/17) vs 11.8% (2/17) (OR 3.12; 95% CI, 0.52;19.38; P= .398). No patient had nephrotoxicity or ototoxicity in either group. CONCLUSION: Suprafascial vancomycin powder in open instrumented spinal fusion surgery is safe and results in negligible systemic uptake. Final results of the VANCO Trial need to be awaited for conclusive data on the efficacy of vancomycin for SSI prevention and its impact on wound healing.