Blood loss resulting in low hemoglobin (the molecule in the blood that carries oxygen) can cause added neurological damage to those suffering from traumatic brain injuries. To try to prevent this, blood transfusions have been a standard of treatment in intensive care management despite potential side effects.
In an effort to reduce the need for transfusions, researchers from Baylor College of Medicine and Harris Health Ben Taub Hospital used different treatment techniques for traumatic brain injuries during the early hospitalization and found that hemoglobin levels actually can be lower than previously thought before a transfusion is needed, lessening the risks associated with this treatment.
The study, appearing in the current edition of The Journal of the American Medical Association, also found that an anemia drug believed to provide protection for the brain following traumatic brain injury was not as effective in the doses that can be given safely to patients.
“When people with traumatic brain injuries arrive at the hospital, they often have other injuries that can cause a lot of blood loss. The drop in blood pressure caused by the blood loss and the decreased amount of hemoglobin in the blood can reduce the flow of oxygen to the brain,” said Dr. Claudia Robertson, professor of neurosurgery at Baylor and medical director of the Neurosurgical Intensive Care Unit at Harris Health Ben Taub. “These are two issues that we must deal with in the early management of patients with traumatic brain injury. Our goal was to find the most effective treatment plan with the lowest amount of risk.”
Between May 2006 and August 2012, 200 patients with head injuries at two level-1 trauma centers in Houston, Harris Health Ben Taub and Memorial Hermann Hospital, were enrolled in the trial.
Some patients were given erythropoietin, a drug used to treat anemia, and others were given a placebo, along with the appropriate treatment for their specific injuries. Robertson said this drug had been shown to have protective qualities for the brain in a lab setting but in this clinical setting it did not have any significant results.
“While this drug is effective at treating patients with anemia in other disorders, it did not increase hemoglobin concentration, reduce the need for blood transfusion, or improve neurological outcomes for those with head injuries,” Robertson said.
Reducing blood transfusions
To address the need for reducing blood transfusion, the study compared transfusions in two groups of patients. A healthy level of hemoglobin in the blood is around 15 grams per deciliter (g/dL).
Patients with traumatic brain injury are given transfusions when their levels drop to 10, however critically ill patients without traumatic brain injuries are usually not given transfusions until their levels drop to seven.
To compare the two hemoglobin transfusion levels, one group of participants were given transfusions at 10 g/dl, while another group were transfused at 7g/dl.
“We found that there was no benefit to keeping hemoglobin levels at 10 g/dl. The practice used for other critically injured patients without traumatic brain injury of transfusing only when levels reach seven had the same neurological outcome, and had fewer complications from the transfusions” Robertson said. “These findings are important because it will change the way patients are treated with traumatic brain injuries. By reducing the need for transfusions we are lowering the risk of side effects.”
Others who took part in the study include Drs. Shankar Gopinath and J. Clay Goodman, both with Baylor College of Medicine; Dr. H. Julia Hannay, University of Houston; Drs. Jose-Miguel Yamal and Barbara C. Tilley, both with the University of Texas School of Public Health; and the Epo Severe TBI Trial Investigators.
This study was supported by the National Institute of Neurological Disorders and Stroke (grant #P01-NS38660).