Trauma-Induced Coagulopathy in Rat Models: Assessing Hemostatic Changes in Mild and Severe Traumatic Brain Injuries.

Background

Traumatic brain injury (TBI) has been associated with coagulation disorders, and coagulation and fibrinolytic parameters are frequently monitored in the acute stage of TBI.

Methods

Using a rat closed head injury model, mild and severe TBIs were induced. Blood samples were obtained at five post-injury time points, including 1 day and 1, 2, 3, and 4 weeks, to assess coagulation and fibrinolytic parameters, specifically prothrombin time (PT), partial thromboplastin time (PTT), D-dimer, and fibrinogen.

Results

In mild TBI, all hemostatic parameters remained largely within physiological ranges, despite minor statistical fluctuations in PT and PTT. Conversely, severe TBI resulted in significant elevations of PT (p = 0.00015) and PTT (p = 0.01) during the first week. Additionally, D-dimer levels increased significantly at week 2 (p = 0.024) and week 4 (p = 0.014) post-injury, surpassing the upper limit of normal. Although fibrinogen levels showed a significant increase at week 2 compared to the control group (p = 0.011), they remained within the normal reference range.

Conclusions

While mild TBI is characterized by stable hemostatic markers, severe TBI demonstrates a clear and significant progression from acute coagulation activation to secondary fibrinolysis. These findings suggest that severe TBI-induced coagulopathy is a progressive event requiring extended longitudinal monitoring beyond the initial acute phase.