The ultimate comeback: Bringing the dead back to life

Would this procedure give the doctors a lot more time to fix your stroke and stop the damage from continuing while they work on your clot or bleed? Maybe this could extend the tPA time way beyond 4.5 hours. But I obviously know nothing.
http://www.bbc.com/future/story/20140704-i-bring-the-dead-back-to-life

A radical procedure that involves replacing a patient's blood with cold salt water could retrieve people from the brink of death, says David Robson.

“When you are at 10C, with no brain activity, no heartbeat, no blood – everyone would agree that you’re dead,” says Peter Rhee at the University of Arizona, Tucson. “But we can still bring you back.”
Rhee isn’t exaggerating. With Samuel Tisherman, at the University of Maryland, College Park, he has shown that it’s possible to keep bodies in ‘suspended animation’ for hours at a time. The procedure, so far tested on animals, is about as radical as any medical procedure comes: it involves draining the body of its blood and cooling it more than 20C below normal body temperature.

Once the injury is fixed, blood is pumped once again through the veins, and the body is slowly warmed back up. “As the blood is pumped in, the body turns pink right away,” says Rhee. At a certain temperature, the heart flickers into life of its own accord. “It’s quite curious, at 30C the heart will beat once, as if out of nowhere, then again – then as it gets even warmer it picks up all by itself.” Astonishingly, the animals in their experiments show very few ill-effects once they’ve woken up. “They’d be groggy for a little bit but back to normal the day after,” says Tisherman.

Tisherman created headlines around the world earlier this year, when he announced that they were ready to begin human trials of the technique on gunshot victims in Pittsburgh, Pennsylvania. The first patients will have been so badly wounded that their hearts have stopped beating, meaning that this is their last hope. “Cheating death with ‘suspended animation’” is how CNN put it; “Killing a patient to save his life” was the New York Times’ take.

This last paragraph is of most interest to us.

Kick-starting the heart is only one half of the doctor’s battle, however; the lack of oxygen after a cardiac arrest can cause serious damage to the body’s vital organs, particularly the brain. “Every minute that there’s no oxygen to those organs, they start dying,” says Tisherman. His former mentor, Safar, came up with a solution to this problem too, with ‘therapeutic hypothermia’, a procedure that involves cooling the body, typically to around 33C by placing ice packs around the body, for instance. At lower temperatures, cells begin to work in slow motion, reducing their metabolism and the damage that could be caused by oxygen starvation.