Well, here's something you can ask the doctors - the South Pole is high up, and also the atmospheric pressure there is lower than in North America - so, adding these two factors together, how high a mountain in North America would you have to climb to experience the partial pressure of O2 that you're experiencing now?
The highest I've ever been is 14,000 feet. I've done light carpentry work at 12,500 feet and believe me when I stand up suddenly at that altitude I get all woozy. when I put down a tool, it takes me a minute to figure out where I've put it. Everything just takes longer, takes more effort, and I make dumb mistakes.
Are these the conditions under which you're working? Mike Wing