From Now On, Billy Crystal Is My Doctor.

There is no truth like that contained in the Princess Bride.  Why are people dead?  Because their cells are dead.  Why are their cells dead?  Because they're out of oxygen.  How long does that take?  About an hour.

Scientists have been studying the effects of oxygen on the body and have come up with some interesting results.  They contend that brain damage occurs after about 7 minutes of oxygen deprivation, not because of the lack of o2, but because of the sudden rush of the gas when resuscitation occurs.  The mitochondria freak out and hit the self destruct switch and poof, no more brain function.  Researchers are instead investigating a way to refrigerate newly dead specimen and slowly reactivate cells to prevent full on death.  Which explains why Billy Crystal used a bellows to revive our mostly dead hero.

• Damn Interesting » Beware the Dangers of Oxygen