2045 Intraoperative 0.05% Chlorhexidine Gluconate (CHG) Irrigation Reduces Surgical Site Infections in Thoracolumbar Spine Trauma

INTRODUCTION: Surgery for traumatic thoracolumbar injuries carries nearly twice the risk of surgical site infection (SSI) compared to elective fusion for lumbar degenerative disc disease. Efforts to mitigate infection risks include dilute antibiotic and/or antiseptic (povidone-iodine) irrigation and vancomycin powder. Despite being available as a topical antiseptic in spine surgery for over 50 years, to date there is no literature on the use of intraoperative chlorhexidine gluconate (CHG) irrigation. METHODS: Retrospective review of patients undergoing spine surgery for traumatic thoracolumbar injuries between 2017-2023. Rates of SSI were compared among cases using diluted antibiotic irrigation with or without the addition of 0.05% CHG irrigation (450 mL/bottle). Clinical and surgical data were collected from the electronic medical records, including: age, sex, BMI, obesity, diabetes mellitus, tobacco use, spine region, number of intervertebral levels, surgery time, estimated blood loss, and subfascial vancomycin powder. Statistical analysis was performed using student's t-test and chi-squared or Fisher's exact tests (p < 0.05). Potential confounding variables for SSI were evaluated using bivariate analysis and multiple logistic regression. RESULTS: 210 patients (82 control, 128 CHG) met inclusion criteria. There were no significant differences in patient demographics or surgical data besides greater utilization of vancomycin powder in the CHG group (43.0% vs. 20.7%, p < 0.005). There was a trend towards significantly fewer SSI with CHG irrigation (4.7% vs. 12.2%, p = 0.083). After controlling for potentially confounding variables including vancomycin powder, there was a significantly reduced risk of SSI with CHG irrigation (aOR 0.26 [95% CI; 0.06-0.83]; p = 0.028). The number needed to treat (NNT) to prevent one SSI was 11 patients. CONCLUSIONS: This is the first investigation of intraoperative 0.05% CHG irrigation during spine surgery, showing a significant 62% reduction in the incidence of SSI in the setting of thoracolumbar spine trauma.