HIGH-TECH medicine can now save the lives of people injured in accidents that a generation ago would have proved fatal. But it still can do little to heal a severe brain injury.
“We’ve looked at dozens of drugs and treatments over the years, and we’ve never found one that’s effective,” said Dr Kenneth Smith, director of neurosurgery at St Louis University in the United States. “We’re kind of stuck.”
So Smith and other researchers are trying a different approach. As part of a new, unusual study, they will put people with severe blunt-force brain injuries in a state of hypothermia – lowering body temperature to as low as 93°F (33°C) degrees. Patients will spend 48 hours wrapped in cooling blankets before being gradually warmed to the standard 98.6°F (37°C) degrees.
The US government-funded study of 220 patients will take place at 10 medical centres around the country, with results expected in about two years.
Interest in the healing effects of hypothermia stems from headline-making reports of people who have fallen into icy lakes or rivers, been submerged in freezing water for long periods of time, and survived. Experts have also observed that people who were exposed to cold after a traumatic brain injury seemed to retain better brain function.
Doctors believe that the cold stabilises the blood vessels and blocks the release of chemicals that damage the brain. “Maybe if we keep things cool, the brain wouldn’t release these toxic substances,” said Smith, an expert on brain injury and an investigator in the study.
An earlier study found that patients who received hypothermia recovered better than those who had traditional care. However, patients age 45 and younger appeared to benefit the most. Older patients tended to suffer more complications, such as irregular heartbeats and problems with blood clotting.
Under the current study guidelines, people under age 45 who arrive at the hospital with a low body temperature will be put into hypothermia or treated in the usual manner. The typical treatment for hypothermia is to give oxygen, monitor pressure in the brain, watch for swelling or blood clots and treat any complications that arise.
It’s not unusual for brain-injury patients to arrive at the hospital with a low body temperature simply because of accidents that occur outdoors in winter weather. Also, the body often loses its ability to regulate temperature after a coma-inducing injury.
Researchers received permission from the Department of Health and Human Services to apply hypothermia to some patients even if consent from the patient or a relative cannot be obtained.
“That is very unusual,” Smith said. “But in this case, if we didn’t do that we would be discriminating against a lot of people (for whom consent couldn’t be obtained). It was also felt, since the risks of the treatment are very low, that few people would say no.” - LAT-WP