Why I blogged a while back about how anesthesiologist Patrick Kochanek had created “zombie dogs” — canines that were officially brain-dead for three hours, then slowly brought back to life. What I didn’t know is that he’s part of an apparently booming new field of “resuscitation science,” medical research aimed at dramatically refashioning our ideas about how to bring nearly-dead people back from the brink.

Some of the discoveries are pretty wild. According a piece in Newsweek, Lance Becker — another emergency-medicine expert — has recently made headway in grappling with one of the biggest mysteries: Why do we die when our oxygen flow is cut off? Traditionally, doctors have assumed it’s because our cells need oxygen to live, so they die when they’re deprived. But that theory was dealt a big blow when scientists finally started looking at oxygen-starved cells under a microscope, only to find that they survived just fine for up to several hours when cut off from blood flow (and thus oxygen).

Becker, in contrast, discovered something really nuts: That when you deprive cells of oxygen for more than five minutes, they die not because of an immediate lack of oxygen. They die when the oxygen supply is resumed.

Why? As Newsweek reports:

Biologists are still grappling with the implications of this new view of cell death — not passive extinguishment, like a candle flickering out when you cover it with a glass, but an active biochemical event triggered by “reperfusion,” the resumption of oxygen supply. The research takes them deep into the machinery of the cell, to the tiny membrane-enclosed structures known as mitochondria where cellular fuel is oxidized to provide energy. Mitochondria control the process known as apoptosis, the programmed death of abnormal cells that is the body’s primary defense against cancer. “It looks to us,” says Becker, “as if the cellular surveillance mechanism cannot tell the difference between a cancer cell and a cell being reperfused with oxygen. Something throws the switch that makes the cell die.”

The implications for ER medicine are huge. If Becker’s right, current emergency practices actually kill people — because when you’re brought into the ER and you’re not breathing, the first thing they do is flood you with oxygen. But all that does, Becker claims, is radically accelerate the speed at which your cells die. What ER doctors ought to do instead, he theorizes, is chill your body down and very, very slowly warm it up while gradually reintroducing oxygen.

Which sounds, now that I go back and look at it, rather like the zombie-dog experiment. Either way, this resuscitation area is bound to get curiouser and curiouser as time goes on.

(Thanks to Plastic for this one!)