- The Washington Times - Monday, May 23, 2005

ASSOCIATED PRESS

For 24 hours, Hamilton Loeb lay unconscious inside a cold blue suit that put his brain on ice.

Four times, his heart had stopped beating, and he was shocked back to life. Then doctors essentially refrigerated him in a bid to avert the brain damage that often cripples survivors of cardiac arrest.

Today, the 53-year-old lawyer is back to normal, and he credits the cold with protecting his brain.

Chilling the sick may sound counterintuitive, but research shows that mild hypothermia — cooling the body just a few degrees — can significantly improve the odds of a full recovery after cardiac arrest. Now scientists are trying to prove whether a cool-down can protect against some of the damage from other disorders, too.

Last month, a study of 75 children with head injuries concluded that inducing hypothermia reduced the dangerous brain swelling that accompanies these injuries — and there were signs that it may also help the youngsters’ cognitive function.

And for stroke victims, the National Institutes of Health is funding new research to see whether chilling extends the narrow window of time they have to get a lifesaving treatment that restores blood flow in their brains.

Yet, while medical guidelines already urge inducing hypothermia in cardiac-arrest survivors such as Mr. Loeb, few hospitals routinely offer it, laments Dr. George Lopez, a neurologist at the Baylor College of Medicine.

Perhaps the biggest hurdle is how to chill people: The body fights mightily, by shivering, to stay at 98.6 degrees, and packing ice or old-fashioned cooling blankets into hospital beds is a messy and hard-to-control way to overcome that resistance.

Mr. Loeb was lucky on that day last December. His 17-year-old son, Max, saw his father collapse and kept calm enough to perform CPR, buying him time until paramedics arrived to restart his heart with jolts of electricity.

But Mr. Loeb’s heart kept stopping on the way to the hospital, and doctors didn’t know how many minutes without oxygen had added up.

So once Mr. Loeb’s heartbeat finally stabilized, doctors encased him in the Arctic Sun suit — special pads that look like a bright blue vest and shorts and are stuck to the skin with a gel. Cold water rushes through tiny channels in the pads, simulating immersion in water.

Within about an hour, the padded suit made by Medivance Inc. had dropped Mr. Loeb’s body temperature to 91 degrees.

Studies show that cardiac-arrest survivors treated with hypothermia were up to 40 percent more likely to avoid lasting brain damage. Chilled patients were also slightly more likely to live.

First, the cold reduces the brain’s need for oxygen.

However, once blood flow resumes, a vicious chemical chain reaction continues to kill brain cells, as harmful proteins spewed by dying neurons in turn take out their neighbors. Just as fruit lasts longer in the fridge, hypothermia slows that process, allowing injured brain cells to recover.

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