X-Message-Number: 12587 Date: Sun, 17 Oct 1999 19:56:11 -0400 From: Jan Coetzee <> Subject: Hypothermia Device Induces Hypothermia To Treat Stroke Victims By Deena Beasley LOS ANGELES (Reuters) - Hypothermia, the subnormal body temperature feared by mountain climbers, may soon be induced with pinpoint accuracy to limit brain damage in stroke and heart attack victims, according to some medical experts. Mild hypothermia helps reduce the damage caused by the lack of nutrients and oxygen, as well as the release of toxins, that occurs when a blood clot or swelling from trauma blocks blood flow to the brain. Diminished or obstructed blood flow can lead to death, paralysis, blindness and speech problems. ``We feel, based on experiments, that this method of protecting brain cells would widen opportunities for patients,'' Gary Steinberg, chairman of neurosurgery at Stanford University, in Palo Alto, Calif., explained in a recent interview. ``We may be able to prolong the window of time before damage occurs.'' Currently, doctors can induce hypothermia in anesthetized, typically pre-operative, patients through surface cooling with blankets or even external blood recirculation pumps. But the techniques are slow, cumbersome to administer, involve risk of cardiovascular side effects, and in the case of the external pump, extremely invasive. San Diego-based Innercool Therapies Inc. said it has developed a disposable catheter tipped with a flexible metallic element and attached to a small cooling unit, that can be used in both arteries and veins to precisely control cooling. ``According to the latest data, patients benefit when blood vessels are opened within six to eight hours of a stroke,'' John Doback, M.D., Innercool's chief executive officer, said. The company plans to begin human clinical trials of the cooling device early next year. Recent animal studies show that Innercool's system can cool brain tissue by five degrees Celsius within 30 to 60 minutes. Steinberg, one of the company's scientific advisors, said the new technology has the potential to cool the brain much more quickly that conventional methods and achieve those temperatures with greater reliability and accuracy. ``The hope is that we will be able to treat not only surgical patients, but be able to treat patients in the field on an emergency basis,'' the neurosurgeon said. The neuron-protecting hypothermic therapy might also be combined with existing clot-busting drugs that open up blood vessels in stroke victims, Steinberg suggested. Doback noted that each year up to 250,000 Americans suffer strokes damaging enough to affect speaking ability. Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=12587