MONDAY, Aug. 29 (HealthDay News) -- Caution is required when deciding whether to stop life support for patients with traumatic brain injuries, a new study suggests.

Researchers examined death rates after life support was halted for 720 patients over age 16 with severe traumatic brain injury in six trauma centers in the Canadian provinces of Ontario, Quebec and Alberta.

Overall, about one-third of the patients died in hospital, but the rate varied from 11 to 44 percent -- depending on the different trauma centers, according to the study published Aug. 29 in the Canadian Medical Association Journal.

"We saw that most deaths after severe traumatic brain injury occurred after withdrawal of life-sustaining therapy and that the rate of withdrawal of life-sustaining therapy varied significantly across level-one trauma centers," wrote Dr. Alexis Turgeon of Laval University in Quebec, and coauthors.

Seventy percent of the deaths (a range of 64 percent to 76 percent among centers) were associated with the withdrawal of life support, and about half of these deaths occurred within three days, the authors noted in a journal news release.

The team also found "considerable variability" in the death rate between the hospitals, even after adjusting for various risk factors. "This raises the concern that differences in mortality between centers may be partly due to variation in physicians' perceptions of long-term prognosis and physicians' practice patterns for recommending withdrawal of life-sustaining therapy," the team stated.

Therefore, until accurate diagnostic tools are available, caution is required when estimating prognoses for patients with severe traumatic brain injuries and when recommending the withdrawal of life support, the researchers concluded.

More information

The Society of Critical Care Medicine has more about life support.