PHILADELPHIA – according to an investigation presented at the annual meeting of the American Academy of Neurology. For patients with TBI and intracranial hemorrhage (ICH), however, treatment with a 2-gram bolus of tranexamic acid within 42 minutes of injury significantly improves the rate of 28-day survival. Tranexamic acid therefore “is the first therapeutic with evidence for benefit in acute TBI,” said Susan Rowell, MD, trauma medical director at Duke University in Durham, North Carolina.
No effective treatment is available for TBI, which is a major cause of death after trauma. In 2010, the(Lancet. 2010 Jul 03;376:23-32), suggested that tranexamic acid, a lysine analogue that decreases the breakdown of clots, safely reduced the rate of death from hemorrhage in patients with trauma and bleeding. Patients treated within 1 hour of injury were significantly more likely to survive than those treated at 1 hour or more after injury.
Two small, prospective trials failed to show that tranexamic acid reduced in-hospital mortality, improved neurologic function at discharge, or reduced the progression of ICH. A meta-analysis of both trials, however, showed a trend toward a benefit of treatment with this therapy.
A multicenter, prehospital trial
Dr. Rowell and colleagues hypothesized that prehospital administration of tranexamic acid to patients with moderate to severe TBI early after injury would increase the likelihood of a favorable neurologic outcome. Between March 2015 and March 2017, they enrolled 1,280 participants in a multicenter, prehospital trial. Eligible participants had moderate to severe TBI, were not in shock (as evidenced by a systolic blood pressure greater than 90 mm Hg before randomization), and were enrolled within 2 hours of injury.
Patients were randomized to one of three treatment arms and followed for 6 months. The first treatment arm received a 1-gram bolus of tranexamic acid before hospital admission and an 8-hour, 1-gram infusion of tranexamic acid in the hospital. The second arm received a 2-gram bolus of tranexamic acid before hospital admission and a placebo infusion in the hospital. The third arm received a placebo bolus and placebo infusion. Paramedics and participants were blinded to treatment assignment. The trial was conducted at 20 hospitals and 39 emergency medical services agencies in the United States and Canada.
The study’s primary outcome was functional neurologic outcome at 6 months, as measured by the Glasgow Outcomes Scale – Extended (GOSE). The investigators dichotomized results into favorable and poor categories. Other prespecified outcomes included early and late mortality, the disability rating scale (DRS), and progression of ICH.
Treatment was administered early
The researchers identified 1,280 eligible patients, of whom 1,063 were randomized. The modified intention-to-treat analysis included 309 participants in the placebo group, 312 in the bolus-maintenance group (the 1-gram group), and 345 in the bolus-only group (the 2-gram group). The population’s average age was approximately 42 years, and 75% of the sample was male. About half of the patients had a Glasgow Coma Scale score between 3 and 8. Injury severity and prehospital care were similar among the groups.