Timing of Preoperative Surgical Antibiotic Prophylaxis Prior to One-to-Three Level Elective Lumbar Fusion

Introduction: Surgical site infections (SSIs) in patients who have undergone lumbar fusion surgery can be a devastating complication. The aim of this study was to examine the relationship between timing of preoperative antibiotic prophylaxis and adverse outcomes such as SSIs with subgroup analysis stratified by antibiotic type. Methods: This retrospective cohort included patients having undergone a 1-3 level lumbar fusion who were allocated into 5 groups based on the time from antibiotic administration to incision (Group A = 0-15 min, Group B = 16-30 min, Group C = 31-45 min, Group D = 46 – 60 min, and Group E = 61+ min). The primary outcome was SSIs, with secondary outcomes including: 90-day readmission and revision surgery. Statistical analysis, including a logistic regression model, was used to examine the relationship between patient/case characteristics, preoperative antibiotic timing, and postoperative outcomes. Results: From 1,131 patients, 26 SSIs were identified. Logistic regression analysis revealed that Group E patients were 1.4 times more likely to develop an SSI and 7.2 times more likely to be readmitted within 90 days compared to Group A. Furthermore, Groups B-D did not have significantly higher odds of infection compared to Group A. Patients treated with vancomycin showed the lowest incidence of SSI when administered between 16-30 minutes, however cefazolin showed the lowest incidence when administered between 0-15 minutes. Discussion: Preoperative antibiotic administration beyond one hour is associated with higher rates of SSI. Furthermore, vancomycin use is optimal when administered between 16 and 30 minutes prior to incision. While antibiotic prophylaxis effects depend on patient characteristics and varying pharmacokinetics, an effective regimen can significantly improve patient outcomes

Serotonin Reuptake Inhibitor Increases Pseudarthrosis Rates in Anterior Cervical Discectomy and Fusions

STUDY DESIGN: Retrospective cohort. PURPOSE: To determine (1) the effects of serotonin reuptake inhibitors in pseudarthrosis rates after anterior cervical decompression and fusion (ACDF) and (2) to identify patient-reported outcome measures in patients taking serotonin reuptake inhibitors. OVERVIEW OF LITERATURE: Recent literature suggests that selective serotonin reuptake inhibitors (SSRIs) may inhibit fracture healing via downregulation of osteoblast differentiation. Spinal fusion supplementation with osteoblast-rich substances enhances spinal fusion, thus SSRIs may be detrimental. METHODS: Patients with 1-year postoperative dynamic cervical spine radiographs following ACDF were grouped into serotonin reuptake inhibitor prescriptions (SSRI, serotonin-norepinephrine reuptake inhibitor [SNRI], or tricyclic antidepressant [TCA]) and no prescription (atypical antidepressant or no antidepressant). Pseudarthrosis was defined as ≥1 mm interspinous process motion on dynamic radiographs. Logistic regression models were controlled for confounding to analyze pseudarthrosis rates. Alpha was set at p - values of \u3c0.05. RESULTS: Of the 523 patients who meet the inclusion criteria, 137 (26.2%) were prescribed an SSRI, SNRI, or TCA. Patients with these prescriptions were more likely to have pseudarthrosis (p =0.008) but not a revision surgery due to pseudarthrosis (p =0.219). Additionally, these patients had worse 1-year postoperative mental component summary (MCS)-12 (p =0.015) and Neck Disability Index (NDI) (p =0.006). The multivariate logistic regression analysis identified SSRI/SNRI/TCA use (odds ratio [OR], 1.82; 95% confidence interval [CI], 1.11-2.99; p =0.018) and construct length (OR, 1.91; 95% CI, 1.50-2.44; p CONCLUSIONS: Patients taking serotonin reuptake-inhibiting antidepressants are at increased risk of worse postoperative outcome scores, including NDI and MCS-12, likely due to their underlying depression. This may contribute to their greater likelihood of having adjacent segment surgery. Additionally, preoperative use of serotonin reuptake inhibitors in patients undergoing an ACDF is a predictor of radiographic pseudarthrosis but not pseudarthrosis revision