Tissue injury
All traumatic injuries invariably lead to tissue damage
although the severity of tissue injury varies widely. Crush
injuries are associated with maximum tissue damage. The
severity of the injury closely correlates with the degree of
coagulopathy.2 Tissue injury leads to activation of both clotting
and fibrinolytic systems. Endothelial tear and damage
which occurs due to tissue trauma leads to activation of
coagulation system as the injury leads to exposure of tissue
factor and subendothelial collagen type III, which activates
coagulation proteases leading to thrombin and fibrin formation
at the site of exposure.
Polytraumatic injury results in tissue factor (TF) thromboplastin
release from damaged cells. Acute coagulopathy of
trauma (ACT) occurs early and results from tissue hypoperfusion
and the tissue injury. Coagulopathy associated with
traumatic brain injury (TBI) results from the interplay of various
factors. Because of the high concentration of tissue factor in the
brain tissue, TBI has believed to be associated with a greater
degree of coagulopathy compared with injury in other body
systems.4