What is the recommended TXA dose and time window for battlefield trauma?

• A. 2 grams IV/IO within 6 hours.
• B. 1 gram IV/IO within 24 hours.
• C. 0.5 gram IV/IO immediately.
• D. 1 gram IV/IO as soon as possible, ideally within 3 hours of injury.

Answer: (D)

Early use of tranexamic acid in battlefield trauma aims to prevent excessive breakdown of clots after injury. It does this by blocking plasminogen’s transformation into plasmin, helping to stabilize clots and reduce ongoing bleeding. The most important factor is timing: the survival benefit is strongest when TXA is given as soon as possible and within about 3 hours of injury. The standard dosing approach is a 1 gram IV or IO bolus given promptly, with a second 1 gram dose over the next 8 hours if bleeding persists. In austere, combat settings, delivering 1 gram promptly and aiming for within 3 hours captures both the mechanism and the critical window for benefit. The other options involve dosing or timing that either is not the standard regimen or misses the optimal window for effectiveness.