ability to absorb oxygen in your body is dramatically decreased. the air is very thin up there. he probably would have passed out and was not experiencing anything after a couple of minutes. but what is interesting, the super cold probably threw his body into almost a state of hibernation, suspended animation, like it is hibernating, and when he came back down to the warmer air, with oxygen, he was probably able to wake up. >> it is incredible he survived and is functioning. other people have had brain damage -- >> you worry about the oxygen getting to the brain. we do this in the operating room sometimes, super chill the body so that the brain doesn't just demand the oxygen. you couldn't have planned this. it is remarkable that it