Thrombelastography (TEG®) based dosing of enoxaparin for thromboprophylaxis: a prospective randomized trial

Principal Investigator: Martin A. Schreiber, MD
Lead Institution: Oregon Health & Science University (OHSU)
Participating Sites:  University of Texas Health Science Center at Houston, and University of Washington at Harborview

A standard dose of enoxaparin is used in high risk trauma patients to prevent thromboembolic complications (deep vein thrombosis (DVT) and pulmonary embolus (PE)). Recent data suggest that standard dosing of enoxaparin may be inadequate in the critically ill or obese patient. Anti-Factor Xa levels (aFXa) measure the relative inhibitory activity of enoxaparin on the clotting process, but accuracy, cost, and availability remain problematic. Therefore, using aFXa to determine if patients are receiving correct dosing may be inadequate. Thrombelastography (TEG®) is a real-time assay that can evaluate clot formation and breakdown.

Previously, Schreiber and others demonstrated that TEG® can distinguish patients who will develop DVT while aFXa cannot. Based on that finding, this prospective interventional study of trauma patients who received enoxaparin for DVT prevention evaluated standard or variable dosing of enoxaparin. It was hypothesized that TEG® based dosing is superior to standard dosing for the prevention of thromboembolic events without increasing the incidence of major bleeding complications. However, the researchers concluded that TEG-adjusted enoxaparin administration was not supported and further investigation into the effects of platelet activation in trauma patients is needed.