Intrawound Vancomycin Powder Reduces Delayed Deep Surgical Site Infections Following Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective.

OBJECTIVE: Evaluate whether the use of vancomycin powder (VP) placed in the surgical site prior to wound closure prevents delayed deep surgical site infections (DDI).

SUMMARY OF BACKGROUND DATA: DDI after posterior spinal fusion (PSF) in adolescent idiopathic scoliosis (AIS) patients remains a significant major complication. The use of VP to prevent acute surgical site infection has been reported but the impact on DDI is unknown.

METHODS: AIS patients treated over the past 20 years with PSF/instrumentation from a large muti-center registry were reviewed. Patients were divided into two groups: intraoperative vancomycin powder placed in the wound (VP) or no antibiotics placed in the wound (NVP). DDI was defined as an infection that occurred >90 days after surgery and required surgical intervention in the operating room. Patients who developed a DDI had secondary verification of VP use or not. Chi square and Kaplan-Meier (K-M) survivorship analyses were used to compare demographics and incident rate of DDI between groups.

RESULTS: 4145 cases met inclusion for this study. A total of 43 DDI cases were identified (1.0%). The incidence of DDI for the VP group was 0.2% (4/2111), and 1.9% (39/2034) in the NVP group (P<0.001). Given the difference in follow-up for the 2 groups a Cumulative Survival and Kaplan-Meier analysis revealed the VP group had significantly better "survival" (no DDI) than the NVP group (P<0.001).

CONCLUSION: DDIs are significant, adverse events that can greatly complicate patient recovery after PSF for AIS, including rehospitalization. This study found that patients who received VP intraoperatively were 10 times less likely to develop a DDI than those who did not receive VP. Although other advances/changes in surgical techniques may contribute to the significant decrease in infections found in the more recent VP cohort, VP should be considered as a prophylactic measure.