My condolences to his family, may he rest in peace poor laddie. Others, please don't prejudge this situation - it is completely outwith your experience. If someone gets blind and unco-ordinated above 8000 meters, they almost certainly have high altitude cerebral oedema and are effectively unsaveable. To quote your rescue chances from Rob Hall, who summitted Everst 6 or so times, "you might as well be on the dark side of the moon" He's still up there as well, having died in 1996. If climbers try to stay with someone too long at that height, you just end up with more corpses. BTW, I climbed for 25 years or so - I know what I'm on about for once.