This month, Martin A. Schreiber, MD, and his team published an article in JAMA Surgery online, following the completion of a study funded by the Department of Defense through the National Trauma Institute (NTI). The randomized clinical study compared patient outcomes for those administered standard vs. TEG-adjusted prophylactic enoxaparin dosing. The researchers found that the time to enoxaparin initiation was more rapid than prior studies and the incidence of VTE was low and similar in both groups.
The data suggest that a difference in reaction time of more than 1 minute to initial fibrin formation comparing standard kaolin and heparinase TEGs may be associated with a decreased risk of venous thromboembolism (VTE); however, the study population may have been too limited to reveal significant results. “Low VTE incidence may be due to an early time to enoxaparin initiation and an overall healthier and less severely injured study population than previously reported,” note the researchers. Of the 185 trial participants, only 22 achieved a difference in reaction time greater than 1 minute despite increased enoxaparin dosing in the treatment group.
Risk factors for VTE were identified as older age, higher body mass index, increased Acute Physiology and Chronic Health Evaluation II score and more missed doses per patient.
As VTE is a major cause of potentially preventable death in trauma patients, related studies are important. One recommendation arising from this work is to improve compliance with dosing protocols (almost all the subjects missed at least one dose). Because the results were inconclusive, follow-on research focusing on patients with more severe injuries and prolonged hospital stays—during which there would be additional follow-up over time—is recommended. “These data demonstrate that many trauma and surgical patients are hypercoagulable at baseline and that further investigations into the effects of platelet activation, obesity, time to enoxaparin administration, and AT-III deficiency are needed.”