11. Prophylactic use of local vancomycin does not decrease acute surgical site infection in adolescent idiopathic scoliosis

BACKGROUND CONTEXT Perioperative surgical site infections for adolescent idiopathic scoliosis after posterior spinal fusion range from 0.3-1.6%. Morbidities associated with infections include hospital readmissions, reoperations, and long-term antibiotic use. Prophylactic and local administration of vancomycin powder into the wound has been shown to decrease rates of surgical site infections among the adult population, and many pediatric deformity surgeons have adopted its use in an effort to decrease infections in the adolescent idiopathic scoliosis population. However, efficacy has not been established in this population. PURPOSE The purpose of this study is to investigate the efficacy of prophylactic, local application of vancomycin powder in decreasing surgical site infections in the adolescent idiopathic scoliosis population following posterior spinal fusion. STUDY DESIGN/SETTING Retrospective cohort study PATIENT SAMPLE Patients OUTCOME MEASURES Our primary outcome was the incidence of surgical site infection following posterior spinal fusion. Secondary outcomes included: demographics, surgical data, and infectious data. METHODS A multicenter, retrospective database query of 9 sites belonging to an organization of nonprofit medical facilities was performed for data from January 2008 to February 2019. ICD-9, ICD-10 and CPT codes were used to identify adolescent idiopathic scoliosis patients who underwent posterior spinal fusion. Identified patients were then separated into 2 groups. The vancomycin group had application of prophylactic, local vancomycin into the wound prior to closure and the nonvancomycin group had no local vancomycin added. Demographic and surgical data was compiled and SSI rates were tabulated and compared between the 2 groups. RESULTS A total of 1,917 adolescent idiopathic scoliosis patients underwent posterior spinal fusion from January 2008 to February 2019. Differences in age, body mass index, female to male ratio, and fusion levels were not statistically significant (p>0.05). The vancomycin group had 1,252 (65.3%) patients with 6 (0.48%) diagnosed with a surgical site infection, compared to 665 (34.7%) patients with 5 (0.75%) diagnosed with a surgical site infection in the nonvancomycin group (p=0.45). Of the 6 infections in the vancomycin group, 4 cultures were positive for gram-negative bacteria. Among the 5 infections in the nonvancomycin group, only 1 culture returned positive for gram-negative bacteria. CONCLUSIONS The prophylactic use of local vancomycin did not demonstrate significantly decreased rates of surgical site infections in adolescent idiopathic scoliosis patients undergoing primary posterior spinal fusion (0.48% vs 0.75%). Further studies are required to elucidate the effectiveness of the use of vancomycin in this population. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.