Novel Approaches to Establishing Regional Brain Hypothermia

Brain cooling is the most promising approach to protect the brain from injury due to low blood flow (ischemia). Most lay public is familiar with the miraculous stories of exciting survival from near drowning in ice cold bodies of water. The capacity of cooling to limit brain injury from ischemia has been validated in numerous experimental models. More recently, human trials on systemic cooling after cardiac arrest (global cerebral ischemia) have shown significant benefit to neurological outcome such that it has become a standard of care for select patients. The most applicable and successful approach to brain cooling is cooling that involves lowering the temperature of the whole body (systemic hypothermia) through external cooling devices or indwelling cooling catheters (we were part of one of the clinical trials that showed the benefit of one of these devices in controlling body temperature in humans) in combination with systemic sedation and inhibition of reflex shivering. The undertaking of systemic cooling is cumbersome and requires escalation of medical care that carries inherent risks such as arrhythmia, pneumonia, and coagulopathy. While the typically dismal outcomes after cardiac arrest showed a favorable risk benefit ratio with systemic hypothermia, its risk profile is somewhat prohibitive with less extreme presentations as in the case of focal cerebral ischemia (ischemic stroke). Why not cool the brain selectively? The primary reason relates to the simple fact that we are made in a manner that protects the brain from “the elements” in the environment. In short, external cooling devices applied to the head simply do not cool the brain. However, we are presently a participant in a multi-center trial on a new promising device that uses a novel approach to selectively and rapidly cooling the brain, and, if successful and safe, it may lead to an exciting breakthrough in our ability to rapidly accomplish regional brain hypothermia in the acute setting.In addition to the above mentioned clinical trial, we have an exciting partnership with our colleague scientists at Argonne National Laboratories. Our collaborative research consortium with them, and development of innovative methods to establish regional hypothermia has been an important thrust of our work together. We are co-inventors with them on a now patented device for creating regional brain hypothermia.