Saline Reduces Mortality for Brain Injury Patients
It results in lower death rates compared to albumin fluid, study finds
WEDNESDAY, Aug. 28, 2007 (HealthDay News) -- A simple change in the way people with traumatic brain injuries are treated initially might make a big difference in their survival odds, a new Australian study suggests.
The study found that using saline rather than albumin fluid to maintain normal fluid volume levels in people with severe brain injuries resulted in nearly double the survival rate at 24 months after the injury.
"We determined that the 2-year mortality rate was significantly high in those patients who received albumin-based fluids compared to those who received saline, particularly those patients with severe brain injuries who presented with traumatic coma," said the study's lead author, Dr. John Myburgh, director of the division of critical care and trauma at the George Institute for International Health, in Sydney.
"Given the significant difference in mortality that we observed, we recommend that albumin-based fluids be avoided for the acute fluid resuscitation of patients with traumatic brain injury," added Myburgh, who's also a professor of critical care at the University of New South Wales.
Results of the study are published in the Aug. 30 issue of the New England Journal of Medicine.
Traumatic brain injury is caused by a sharp blow to the head that often occurs in falls, motor vehicle crashes or from physical assault, according to the U.S. Centers for Disease Control and Prevention. The CDC estimates that about 1.4 million traumatic brain injuries occur annually in the United States, and about 50,000 of those people die as a result of the injury each year. Those who survive may have lifelong disabilities.
Some of the most serious damage to the brain occurs at the time of the injury, and soon after, when the brain swells in response to the injury. Because the brain is an enclosed system, if swelling occurs, brain tissue becomes damaged.
Fluid resuscitation is a common part of traumatic brain injury treatment to ensure normal blood circulation in the brain, according to the study. However, there's been some debate as to what type of fluid would most benefit people with traumatic brain injuries -- saline or albumin fluid. Albumin is the main protein component of human blood.
"Albumin is a very expensive product that has to be purified," explained Dr. Keith Siller, medical director of the Comprehensive Stroke Care Center at New York University Medical Center in New York City. "If they're equally effective, you'd pick the cheaper fluid."
And, in fact, a previous study had compared the two fluids and found no statistically significant difference in the rates of death after 28 days.
But, Myburgh and his colleagues re-analyzed the original data to assess results at 24 months after injury. In the original study, 460 people with traumatic brain injuries were randomly selected to receive either saline or albumin fluid. Slightly more than two-thirds of the participants in each group were classified as having a severe traumatic brain injury.
After two years, the researchers behind the new study found that people with traumatic brain injuries who received albumin had a 63 percent higher risk of dying than those given saline. For those with severe brain injuries, the albumin group had an 88 percent increased risk of death compared to the saline group.
"These are people in very bad shape," said Siller. "If there's anything that can help them have better outcomes, we have to pay attention."
Dr. James Goodrich, director of pediatric neurosurgery at the Children's Hospital at Montefiore in New York City, said, "This is a great study that definitely found a significant difference in the sense of outcomes." But, he added, it just confirms what's already going on in the treatment of people with serious brain injury. "Albumin has pretty much been given up on," he said.
As to why saline might offer some benefit over albumin, Myburgh said the researchers can't explain the difference. "The exact mechanism by which the difference in mortality between saline and albumin remains unclear," he said.
"It's probably one of two things," said Siller. "Either albumin is making the brain swelling worse, or somehow the saline is doing something beneficial that albumin can't."
To learn more about traumatic brain injury, visit the National Institute of Neurological Disorders and Stroke.