Platelet activation during acute phase after multiple trauma.

The acute phase after multiple trauma is associated with both thrombotic phenomena and a bleeding diathesis. To evaluate the activation of platelets, beta-thromboglobulin (BTG) in plasma and serum and thromboxane B2 (TxB2) in serum were measured in 14 patients with multiple trauma. BTG in plasma was significantly increased on days 1, 2 and 10 to 14 after the trauma. The highest median value 90 micrograms/l was measured on day 1. BTG in serum was significantly reduced 1 to 7 days after the trauma (median levels 4450-9100 micrograms/l). TxB2 was significantly reduced (median levels 18-97 ng/l) on days 1 to 14. The increased plasma levels of BTG is due to the posttraumatic activation of platelets in vivo. The reduced levels of serum BTG and TxB2 reflect the deficient functional capacity of circulating platelets to respond to extreme stress. Therefore, platelet count alone may correlate poorly with the haemostatic potential and may underestimate the need of platelet transfusions.