Induced hypothermia, a commonly used therapy that lowers one’s body temperature in order to reduce head pressure, may actually hinder recovery in traumatic brain injury patients rather than help them, according to a new international study led by the University of Edinburgh.
The findings show that induced hypothermia may increase patients’ risk of death and disability and should not be used to treat traumatic brain injuries.
The idea behind induced hypothermia is that it helps reduce the build-up of pressure inside the head, which has been strongly linked to long-term disability and death following head injury. The treatment is widely used in some intensive care units in North America and Europe, but there have been few clinical trials to assess the effects on patients’ long-term recovery.
The treatment involves cooling the body between two and five degrees below the normal body temperature of 98.6 degrees Fahrenheit. Patients are given ice cold intravenous drips within 10 days of their injury. They are kept cool using either cold water blankets or cooling pads for at least 48 hours, after which they are gradually re-warmed to normal body temperature.
The major international study tracked the outcomes of almost 400 cases of traumatic brain injuries from 18 different countries. Approximately half of the patients were treated with induced hypothermia to try to protect the brain from further damage caused by swelling. The other half received standard care.
The team found that induced hypothermia was indeed 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.
Positive outcomes, ranging from moderate disability to strong recovery, occurred in only a quarter of the patients in the hypothermia group compared with more than a third of patients in the standard care group. In fact, doctors ended the trial early because of fears that the therapy may cause harm to some patients.
“This well conducted 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,” said Professor Peter Andrews, Head of Critical Care Medicine at the University of Edinburgh.
About two million people experience a traumatic brain injury worldwide each year, mostly as a result of a car accidents or falls. The condition claims 50,000 lives and causes 80,000 people to suffer long-term disability.
The findings are published in the New England Journal of Medicine.
Source: University of Edinburgh