According to New Scientist, traumatic brain injuries can occur as a result of a strong blow, a jolt to the head or an object entering the brain, such as a bullet.

Although it is difficult to predict an individual's progress, some recover and acquire at least partial independence months later. Even so, families often have to decide whether or not to withdraw life-sustaining treatment a few days after a serious injury.

To find out more about the potential outcomes of such events, Yelena Bodien, from Massachusetts General Hospital, and her colleagues collected data for seven and a half years on people who were on life support after a traumatic brain injury in intensive care units in the USA.

Some brain injury patients would recover if life support weren’t ended
After comparing people with brain injuries whose life support was continued with those who had it turned off, scientists calculated that around 40 per cent in the latter group may have made some recovery
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Of these people, 80 had life support withdrawn and their results were compared with those of 56 people in the same situation who continued in treatment, some of whom regained a certain level of independence.

The researchers identified factors associated with the withdrawal of life support, such as the person's age and gender. From there, they used the algorithm to calculate the likelihood of recovery for these people if the treatment had been maintained.

These results suggest that 42% of people who were taken off life support could have survived and acquired at least partial independence six to 12 months after the injury.

“The prognosis after traumatic brain injury is highly uncertain and it is very important to express this uncertainty to families,” says Bodien. “Our results suggest that a more cautious approach is needed when establishing prognosis, a careful analysis is required when making a decision as irreversible as the withdrawal of life support.”

The lack of information on the long-term outcomes of traumatic brain injury is one of the reasons why it is difficult to provide a prognosis, which can lead doctors to assume that a bad outcome is likely and therefore recommend withdrawing life support.

Damian Cruse, from the University of Birmingham in the UK, says that the results should be interpreted with some caution.

“Decisions to withdraw life support are multifaceted and don't necessarily depend on dichotomies such as ‘will they stay in a vegetative state or not?’, but have more to do with whether the level of recovery is something the patient would be satisfied with,” he says.

“That said, it is clear from this and other data that we are not as accurate in our predictions of recovery in the initial period after injury as we would like to be, especially as these predictions will feed into the difficult choices of families.”

The researchers would now like to compare recovery rates after severe traumatic brain injury among people from countries outside the US, says Bodien.

“We are also conducting studies to understand which statistical methods of imputing outcomes are most accurate and could be used in future studies to estimate potential outcomes in patients who die after life support is withdrawn.”

The researchers would now like to compare recovery rates after severe traumatic brain injury between people in countries outside the US, says Bodien.

“We are also conducting studies to understand which statistical methods of imputing outcomes are most accurate and could be used in future studies to estimate potential outcomes in patients who die after withdrawal of life support,” he says.