One is simply ease of use. Let's assume you are in fact at 18,000 or 19,000 feet or higher. Your brain is likely a little addled, and to top it off your hands are probably encased in thick mittens. So you want a camera that's easy to handle and largely foolproof. Another issue is battery life.
Cold weather kills batteries.
So you want to take plenty of spares. And, you want to take steps to ensure the camera is kept close to your body in a pocket, or zipped inside a parka. Lastly, cold and dry weather can lead to static build-up in film. That's caused by static electricity. Hope that helps.