Do Antifibrinolytic Agents Reduce the Risk of Blood Transfusion in Children Undergoing Spinal Fusion? A Propensity Score-Matched Comparison Using a National Database

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To evaluate the effectiveness and safety of antifibrinolytic (AF) agents in reducing perioperative blood transfusion in pediatric patients undergoing spinal fusion. SUMMARY OF BACKGROUND DATA: The potential for AF to decrease bleeding and reduce exposure to allogenic transfusions has led to widespread off-label use in a number of major pediatric surgical procedures. Recent reviews call for improving the body of evidence for their effectiveness and safety in pediatric spinal fusion. METHODS: Children undergoing spinal fusion were identified in the American College of Surgeons National Surgical Quality Improvement Program Pediatric (NSQIP-P) 2016 and 2017 databases. Univariate analyses of patient and perioperative characteristics informed the creation of a propensity score model predicting treatment with AF, followed by 1:1 matching to allow comparison of allogenic red blood cell transfusion rates and secondary outcomes between treated and untreated patients. RESULTS: Of 6626 total patients, 5434 (81%) received AF and 1533 (23%) received a blood transfusion. Analysis of data for 1192 propensity score-matched pairs revealed that treatment with AF was associated with a statistically non-significant 16% reduction in perioperative transfusion (OR 0.84, 95% confidence interval 0.68-1.05, p = 0.119) and a statistically significant 43% reduction in postoperative transfusion (OR 0.57, 95% confidence interval 0.39-0.81, p = 0.002). No differences in the incidences of postoperative seizure or thrombosis were observed, with overall rates of 7.5 and 22.5 events per 10,000 patients, respectively. CONCLUSIONS: AF agents appear to reduce postoperative allogenic transfusion in children undergoing spinal fusion surgery. Adverse drug effects such as thromboembolic complications and seizure were extremely rare and warrant continued monitoring, though this is the largest study to date providing evidence for the safety profile of these drugs. LEVEL OF EVIDENCE: 3.