I am rested this AM after our tour up the W side of the Andes. Going from Lima to 4800+ m in 5 hours is a big jump. At rest my oxygen saturation dropped from 96% at sea level to 69% at Ticlio. It improved to the mid 70s once I got up and around. It was one of the lowest in the group. I felt a little lightheaded so I was reluctant to walk around much on the surrounding rocks. Tandem gait was okay but I was unable to recite a few things that I knew well. It was very difficult to stay focused.
One’s ability to adjust at altitude is highly individual. It depends on climbing strategy and genetics. Above 2500 m or so, the safest and best way is to ascent slowly and take appropriate rest stops. Drugs are sometimes used as well. They fool your body and compensate or provide shortcuts. Purests view them as cheating; highly motivated, goal oriented climbers view them as a way of life. Suffice it to say that we did not take sufficient time for acclimation and no drugs were involved. Normally, I seem to do fine up to 6000 m as long as I take my time. I would like to blame my Mom and Dad (genetics) but my Dad is dead and my Mom wouldn’t know what I was talking about.
Headches are a big feature of altitude travel. Interestingly (at least to me), I did not develop one until an hour or so later, when we were down below 2000 m. While at the top, I did have some scotomata (flashing irregular lights) and obscuration in my peripheral fields. I infrequently have migraine equivalents that are characterized by these kinds of symptoms. The headaches that follow are annoying, not the brain splitters that many people experience. Part of the pathophysiology of migraines has to do with vessel dilation. The same thing happens with altitude because of low oxygen. Curious. Did I have a migraine or an altitude related headache? This has never happened to me at altitude before.
There is also research to suggest that our brains are much more vulnerable to altitude effects when we don’t acclimate. That is a topic for a WMA blog. So what was I doing up there anyway?