Hypothermia therapy for brain injury.

Induced hypothermia is an acknowledged useful therapy for treating conditions that lead to cell and tissue damage caused by ischemia, including traumatic brain injury, stroke, and cardiac arrest. An accumulating body of clinical evidence, together with several decades of research, has documented that the efficacy of hypothermia is dependent on achieving a reduced temperature in the target tissue before or soon following the ischemia-precipitating event. The temperature must be lowered to within a rather small range of values to effect therapeutic benefit without introducing collateral problems. Rewarming must be much slower than cooling. Many different methods and devices have been used for cooling, with mixed results. There are existing opportunities for bioengineers to improve our understanding of the mechanisms of hypothermia and to develop more effective methods of cooling the brain following trauma.