Tranexamic Acid Shows No Symptom Benefit for Traumatic Brain Injuries

Susan E. Rowell, MD

The early administration of tranexamic acid is not beneficial for patients suffering from traumatic brain injuries (TBI), according to new data.

A team, led by Susan E. Rowell, MD, Department of Surgery, Oregon Health & Science University, determined whether tranexamic acid treatment initiated in the out-of-hospital setting within 2 hours of an injury could improve neurologic outcomes of patients with moderate-to-severe traumatic brain injuries.

In the randomized, multicenter double-blind clinical trial, the investigators examined 966 patients at 20 trauma centers and 39 emergency medical service agencies in the US and Canada between May 2015 and November 2017. The mean age of the patient population was 42 years old and 74% of the participants were male. The mean Glasgow Coma Scale score was 8 and 819 patients ended up in the primary outcome analysis at the six-month follow-up.

Eligible patients included out-of-hospital patients with TBI at least 15 years old with a Glasgow Coma Scale score of 12 or less and systolic blood pressure of 90 mm Hg or higher.

The investigators evaluated 3 different interventions, with treatment initiated within 2 hours of an injury—out-of-hospital tranexamic acid (1 g) bolus and in-hospital tranexamic acid (1 g) 8-hour infusion (bolus maintenance group; n = 312), out-of-hospital tranexamic acid (2 g) bolus and in-hospital placebo 8-hour infusion (bolus only group; n = 345), and out-of-hospital placebo bolus and in-hospital placebo 8-hour infusion (placebo group; n = 309).

The research team sought primary outcomes of favorable neurologic function at 6 months (Glasgow Outcome Scale-Extended score >4 [moderate disability or good recovery]) in the combined tranexamic acid group vs the placebo group. They set the asymmetric significance thresholds at 0.1 for benefit and 0.025 for harm.

There were also 18 secondary endpoints in the study, including 28-day mortality, six-month Disability Rating Scale score range, 0 [no disability] to 30 [death]), progression of intracranial hemorrhage, incidence of seizures, and incidence of thromboembolic events.

Favorable neurologic function was found in 65% of patients in the tranexamic acid group, compared to 62% of the placebo group (difference, 3.5%; 90% 1-sided confidence limit for benefit, −0.9%; P = 0.16; 97.5% 1-sided confidence limit for harm, 10.2%; P = 0 .84).

The researchers did not find a statistically significant difference in the 28-day mortality between the 2 groups (14% vs 17%; difference, −2.9%; 95% CI, −7.9% to 2.1%; P = 0.26).

This was also found in the 6-month Disability Rating Scale score (6.8 vs 7.6; difference, −0.9; 95% CI, −2.5 to 0.7; P = 0.29) and the progression of intracranial hemorrhage (16% vs 20%; difference, −5.4%; 95% CI, −12.8% to 2.1%; P = 0 .16).

“Among patients with moderate to severe TBI, out-of-hospital tranexamic acid administration within 2 hours of injury compared with placebo did not significantly improve 6-month neurologic outcome as measured by the Glasgow Outcome Scale-Extended,” the authors wrote.

Currently, TBI is the leading cause of death and disability caused by trauma.

The study, “Effect of Out-of-Hospital Tranexamic Acid vs Placebo on 6-Month Functional Neurologic Outcomes in Patients With Moderate or Severe Traumatic Brain Injury,” was published online by JAMA.