If you can't restart a stopped heart within 5 minutes, brain damage starts. But using the lungs as a heat exchanger to chill the blood may buy us more time.
By Michael Brooks
HERE’S a fact that might chill the cockles of your heart: if your ticker stops, you have less than 5 minutes to get it going again before your brain experiences irreversible damage. But there could soon be a way to open that window much wider, thanks to a technique that rapidly cools the body to exploit the life-saving powers of another notorious killer: hypothermia.
It may seem paradoxical, but it all boils down to simple chemistry. You might think of ourself as a biological organism, but at a baser level you are chemical. Chemistry governs the function of your cells, senses, digestion and even your thoughts.
As temperatures fall, chemical reactions slow down. That’s why it isn’t good to get too cold: if you lose too much heat, you slip into hypothermia. Remove enough heat and the reactions eventually shut off completely – a state known to biologists as death.
But here’s the twist: sometimes, especially if death is an imminent danger, cold can be a lifesaver. “Hypothermia has huge benefits,” says Renaud Tissier of the National Veterinary School of Alfort, France.
To harness these, Tissier and his collaborators have built a machine that plunges your body to frigid temperatures in a matter of minutes. How does it work? Take a deep breath and prepare to gag: by pumping a chilled liquid into your lungs.
“To harness hypothermia, the machine pumps chilled liquid into the lungs”