Cerebral hypothermia and circulatory arrest. Review and commentary.

Through the application of low-temperature technology, the critical limits of circulatory arrest to the mammalian brain--the most complex of all body organ systems--can be significantly extended. This presentation reviews three recently developed methods of cooling the brain. The first demonstrates the unique preservation of cerebral tissue as an isolated organ near 0 degrees C with donor perfusion reanimation. The second emphasizes the ability of the intact animal to literally cool its own brain when a simple extracorporeal shunt is utilized. The third outlines a technique of direct hypothermic infusion of the ventricular pathways to achieve deep temperature reductions in brain tissue. Their clinical applications and implications are discussed.