NEW YORK (Reuters Health) – Early administration of tranexamic acid (TXA) improves survival following severe combat trauma involving massive bleeding, according to a study in Archives of Surgery.

These findings “confirm for military surgeons that TXA is ready for prime time use as part of a blood component-based resuscitation following wartime injury,” said first author Dr. Todd E. Rasmussen, US Air Force Medical Corps Deputy Commander, US Army Institute of Surgical Research, Fort Sam Houston, Texas.

“Additional study is underway to determine the mechanisms behind the TXA benefit as well as optimal ways to dose this medication,” he added.

TXA is an antifibrinolytic agent used to control bleeding by preventing clot breakdown with an established safety and efficacy profile, Dr. Rasmussen and colleagues note in their report. To their knowledge, the current study is the first to describe the use of TXA in the management of severe combat injury.

The retrospective observational study compared TXA administration with no TXA in 896 consecutive combat injured personnel who were actively bleeding and received at least 1 unit of packed red blood cells at a surgical hospital in southern Afghanistan; 293 subjects received TXA and 603 did not.

In-hospital death rates were lower in the TXA group (17.4% vs 23.9% in the no TXA group; P = 0.03), the investigators report.

“The most important observation of this study relates to the improved survival in the group of injured patients having received TXA,” Dr. Rasmussen commented.

“What’s most convincing is that this benefit was present in a group of patients who were generally more severely injured than those not receiving the medication.” The Injury Severity Score was 25.2 in the TXA group vs 22.5 in the no TXA group (P < 0.001).

The benefit of TXA was greatest in the subgroup of patients requiring massive transfusion of 10 units or more. In this group, in-hospital death rates were 14.4% with TXA compared with 28.1% without (P = 0.004). In this subgroup, TXA was independently associated with a 7-fold greater odds of survival (odds ratio, 7.228) and less coagulopathy (P = 0.003), the investigators report.

“The UK Defence Medical Service has used TXA since 2009 as part of a massive transfusion protocol, and the US Combat Casualty Care program has deferred use altogether,” the authors note in their paper.

Based on the current findings, they think treatment with TXA “should be implemented into clinical practice as part of a resuscitation strategy following severe wartime injury and hemorrhage.”

“It’s important to emphasize,” Dr. Rasmussen told Reuters Health, “that this type of evidence-based shift in combat casualty care could not take place without robust Joint Trauma Systems in both the US and the UK. These systems and their trauma registries are essential in allowing military surgeons to make these types of life-saving advancements.”

In a commentary, Dr. Kenji Inaba, of the Division of Trauma and Surgical Critical Care, University of Southern California, Los Angeles, says this study provides “further evidence that in trauma patients who are bleeding, tranexamic acid may be beneficial.”

“Thus, the mechanism of action, role of point-of-care tests in directing treatment, dosing and optimal timing all warrant further investigation,” he concludes.

Reference:

Military Application of Tranexamic Acid in Trauma Emergency Resuscitation (MATTERs) Study

Arch Surg 2011. Published online October 17, 2011.