Several small experiments, intended largely to examine whether cooling stroke victims is even feasible, offer tantalizing hints of this. At the Cleveland Clinic, doctors have cooled five victims of especially severe strokes, dropping their temperatures a few degrees for a day or two. Against the odds, two of these five recovered completely. Doctors at the University of Texas in Houston saw similar results cooling victims of cardiac arrest. Like a stroke, cardiac arrest wrecks the brain by shutting off its blood supply.
Victims often suffer permanent brain damage, even if paramedics eventually restart their hearts.
The Houston doctors chilled seven patients who arrived at the hospital in comas after being resuscitated. After a day of cooling, two of them soon returned completely to normal, while another is nearly so. Dr. James Grotta cautions that such examples prove little. Without carefully controlled studies, doctors can only guess how many would get better on their own. I have seen results that in my mind are very dramatic.