Head injury patients do not benefit from a therapy that involves cooling their bodies to reduce brain swelling, international research has found.
In a study, led by Edinburgh University, induced hypothermia did not improve patients’ chances of recovery.
The researchers said the therapy may actually increase patients’ risk of death and disability, and should not be used to treat traumatic brain injuries.
“Hypothermia can successfully reduce brain pressure following trauma, but functional recovery was significantly worse than standard care alone”
Cooling the brain is intended to reduce the build-up of pressure inside the head, which is strongly linked to long-term disability and death following head injury.
The treatment is widely used in some intensive care units in Europe and North America, but there have been few clinical trials to assess the effects on patients’ long-term recovery.
The new study tracked the outcomes of almost 400 cases of traumatic brain injuries from 18 different countries.
Around half of the patients were treated with standard procedures. The other half were treated with induced hypothermia to try to protect the brain from further damage caused by swelling.
Induced hypothermia was successful at reducing the build-up of pressure in the skull after head injury.
Six months later, however, patients who had received the therapy were more likely to fare worse than those treated with standard care.
Favourable outcomes – ranging from moderate disability to good recovery – occurred in only a quarter of the patients in the hypothermia group, compared with more than a third of patients in the control group.
The findings led the researchers to end the trial early because of fears that the therapy may cause harm to some patients.
Induced hypothermia involves cooling the body between two and five degrees below normal body temperature of 37 degrees Celsius.
Patients are given ice cold intravenous drips within 10 days of their accident. They are kept cool using either cold water blankets or cooling pads for at least 48 hours, after which they are gradually warmed.
Professor Peter Andrews, head of critical care medicine at the University of Edinburgh, said: “This trial has shown that hypothermia can successfully reduce brain pressure following trauma, but after six months functional recovery was significantly worse than standard care alone.”
The Eurotherm3235 trial was funded by the National Institute for Health Research’s health technology assessment programme.
The findings have been published in theNew England Journal of Medicine and also presented at the European Society of Intensive Care Medicine annual congress in Berlin on 7 October.