Traumatic brain injury (TBI) is a leading cause of death and disability worldwide. An estimated 20 to 55% of people with TBI will develop venous thromboembolism (VTE), a condition that includes the formation of blood clots in the leg (called deep vein thrombosis; DVT) and the dislodging and travel of one or more of these blood clots into the lung (called pulmonary embolism). Left untreated, VTE can restrict blood flow to important tissues and organs, causing permanent damage or even resulting in death.
Fortunately, several types of medications can reduce the risks associated with VTE. Their mechanisms of action vary but typically either thin the blood, prevent clot formation, or dissolve existing clots. Although these drugs are known to be safe and effective in a standard patient, clinicians disagree about the safety and value of drug treatment for VTE in patients with TBI, with many citing concerns that treatment may increase the size of an existing intracranial hemorrhage. Consequently, there is no standard of care regarding optimal timing of prophylactic (i.e., initiated before a condition occurs to prevent its eventual development) pharmacological treatment for VTE in this patient population.
A recent study addressed this controversy by analyzing medical records and outcomes from 264 TBI patients who were stable at 7 hours after injury, some of whom received early prophylaxis (before 24 hours after injury) and some of whom received late prophylaxis (more than 24 hours after injury) for VTE. To determine the safety of each timing protocol, the research team analyzed the progression of each patient’s brain bleed.
About 40% of patients received early prophylaxis. In this group, the average time to VTE prophylactic treatment was 17 hours, compared to 47 hours in the late group. There were no significant between-group differences in the progression of brain bleeds, the need for head surgery, nor the rate of VTE development.
The researchers concluded that early prophylaxis for VTE is not associated with worsening intracranial hemorrhage among stabilized TBI patients. Further research is necessary to determine optimal timing of prophylaxis to prevent VTE in this population.
Rivas L, Vella M, Ju T, et al. Early chemoprophylaxis against venous thromboembolism in patients with traumatic brain injury. The American Surgeon. (April 2022).