Procoagulant Activity in Trauma Patients

Elevated levels of circulating procoagulants like tissue factor may increase the risk of systemic coagulation activation, thrombin generation, and consumptive coagulopathy. I measured procoagulant activity in plasma by using a clot-based assay that incorporated normal plasma to replace missing factors, corn trypsin inhibitor to block contact activation, factor Vila to improve sensitivity to tissue factor activity, and anti tissue factor antibodies to measure tissue factor specific activity. Procoagulant activity was evaluated in 58 trauma patients. Trauma patients without coagulopathy (n = 50) showed 5-fold higher procoagulant activity than did control subjects (P < .001), whereas trauma patients with coagulopathy (n = 8) showed 10-fold higher activity than control subjects (P < .001) and 2-fold higher activity than trauma patients without coagulopathy (P = .03). In control subjects, tissue factor activity was below the detection limit of the assay. Tissue factor activity was 3- to 4-fold higher in trauma patients with coagulopathy vs patients without coagulopathy (P = .002). Trauma patients with coagulopathy have increased circulating tissue factor activity.