Tranexamic Acid (TXA) Administration Following Head Trauma in a Combat Setting: Does TXA Result in Improved Neurologic Outcomes?

BACKGROUND: Tranexamic acid (TXA) has been shown to decrease mortality and blood product requirements in severely injured patients. Tranexamic acid has also been hypothesized to prevent secondary brain injury in patients with traumatic brain injury. While prior studies have demonstrated improved neurologic outcomes associated with TXA administration in severely injured pediatric patients, no such studies have been performed in adults. METHODS: A retrospective review of all adult trauma admissions to North Atlantic Treaty Organization hospitals in Iraq and Afghanistan between 2008 and 2015. Univariate and multivariate analysis was used to identify factors associated with TXA administration. Patients without a documented head Abbreviated Injury Scale (AIS) were excluded. Patients were propensity matched based on demographics, mechanism of injury, Injury Severity Score (AIS/ISS), presenting Glasgow Coma Scale (GCS) score, initial vitals/laboratory values, and initial transfusion requirement. Primary outcomes were in-hospital mortality and neurologic outcomes measured by discharge GCS scores. Secondary outcomes were respiratory failure and rates of thromboembolic events. RESULTS: Four thousand four hundred seventy-six injured patients 18 years or older were evaluated. Two hundred sixty-five (5.9%) of these patients required a massive transfusion in the first 24 hours, and 174 (3.9%) received TXA. The TXA patients had significantly higher ISS, more penetrating injuries, lower presenting GCS, higher incidence of severe head injury (AIS > 3), and higher transfusion requirements. Ninety-two patients were included in the propensity matched cohort. Of these, patients who received TXA had significantly lower mortality rate (0% vs. 10.1%, p = 0.02) and improvement of GCS score to 14 to 15, irrespective of admission GCS compared with patients who did not receive TXA (100% vs. 87%, p = 0.01). There were no significant differences in number of thromboembolic events recorded between the two groups. CONCLUSION: The TXA administration in adult combat trauma patients was independently associated with decreased mortality and improved neurologic outcomes, with no increase in thromboembolic events. Further study of the possible mechanisms and effect of TXA on brain injury and neurologic outcomes is warranted. LEVEL OF EVIDENCE: Therapeutic, level IV.