Early Initiation of Blood Thinners Effective, Safe in TBI Patients
October 3rd, 2016
TORONTO, CANADA — Initiating blood thinners within 72 hours of hospital arrival significantly lowers the likelihood of life-threatening blood clots in patients with traumatic brain injury (TBI) but doesn't increase the risk of bleeding complications or death, according to a new study.
The article published online by the Journal of the American College of Surgeons notes that pulmonary embolism (PE) is a leading cause of death in patients who sustain a TBI, and that they also are at high risk of developing deep vein thrombosis (DVT).
The University of Toronto-led study suggests that starting blood thinners early can have a significant protective effect against those conditions.
"Physicians have traditionally been hesitant to initiate pharmacological blood clot prophylaxis early in patients with severe brain injuries because, while thinning the blood might prevent PE and DVT, it might also increase the risk of complications related to worsening intracranial hemorrhage," according to lead study author James P. Byrne, MD, a general surgery resident and PhD student at the University of Toronto. "We performed this study because there wasn't clear evidence that starting prophylaxis early actually prevented blood clots, or whether this benefit would outweigh the risk of complications from intracranial hemorrhage. Current evidence-based guidelines don't address the optimal timing for starting prophylaxis in patients with severe TBI."
Background information in the report notes that TBI patients are at higher risk of forming blood clots because of hypercoagulability related to their injuries and long-term immobility.
For the study, researchers analyzed data on 3,634 adult patients with severe TBI who were treated at 186 trauma centers participating in the American College of Surgeons Trauma Quality Improvement Program (ACS TQIP). Included was TQIP data for all patients who had received prophylaxis with either low-molecular weight heparin or unfractionated heparin between 2012 and 2014.
The study sought to compare the effectiveness of early vs. late prophylaxis, and to evaluate the potential risks of worsening intracranial hemorrhage. Patients were divided into two groups: early prophylaxis (started within 72 hours of arrival at the hospital) or late prophylaxis (started after 72 hours), with PE or DVT defined as primary outcomes.
In an effort to characterize complications related to intracranial hemorrhage, the study team also included two secondary outcomes: late neurosurgical interventions (performed after 72 hours) or in-hospital death.
Results indicate that odds of both PE and DVT were 50% lower in the early prophylaxis group than in the late prophylaxis group. On the other hand, no difference was detected with late neurosurgical interventions or in-hospital death between early prophylaxis and late prophylaxis groups.
The study also reports that trauma centers that most frequently used early prophylaxis in their patients had significantly lower rates of DVT, compared with those where fewer patients received early prophylaxis, but no difference in rates of late neurosurgical intervention or mortality.
"The takeaway message is that early prophylaxis really does matter in patients with severe traumatic brain injury, in terms of reducing a patient's risk of pulmonary embolism or deep vein thrombosis," Byrne emphasized. "Our findings suggest that this is possible without increasing the risk of the most feared complications, such as the need to take a patient to the operating room to evacuate intracranial hemorrhage, or death. In other words, it's possible to prevent PE or DVT with early prophylaxis, without putting patients at risk of bad outcomes, and we should be striving to achieve this.”