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(A continuation of High Altitude Brain Damage)


In the research done so far it seems clear that brain damage occurs even in those who do not report any symptoms of altitude sickness. However, those who do have symptoms may suffer even worse damage than those who do not. This suggests that if you have any serious symptoms you should probably get lower right away.

Also, since it is not clear at what altitude damage can occur, even backpackers and hikers in the states may need to be careful. The writer of the article in Outside magazine says he has climbed many mountains over 14,000 feet in the U.S., and his own brain scan showed no meaningful damage, but that is one case. Since it is also clear that the level of damage varies greatly in the same group of people who share a climb, we just don't know what altitude is safe.

Subcortical lesions can result from clots in thickened blood, so another way to protect yourself is to keep fully hydrated. This is very difficult on extreme climbs. To avoid dehydration on Everest climbers would likely have to spend hours each day gathering ice and snow and melting it using their stoves, which would also mean carrying a lot of fuel weight. But backpackers who are just going over a 12,000-foot pass on the John Muir Trail should have plenty of opportunities to fill their water bottles in lakes and streams.

The best medical advice then, is to go slow, stay hydrated, and come down fast if you have any serious symptoms of high altitude sickness.

Altitude - My Own Experiences and Speculation

My head was pounding horribly when I rushed up Mount Shasta (in ratty old shoes), my first big mountain. Fortunately I came down quickly and the pain went away.

On a trip to Colorado years ago (before I lived here), I came from almost at sea level in Michigan, by Greyhound bus. I got off the bus in Silverton and immediately went up to over 13,000 feet. I camped at about 11,500 feet and felt nauseous by morning. I also had hallucinations of sorts. As soon as I descended a thousand feet in the I felt fine.

At 20,700 feet on top of Mount Chimborazo, I can honestly say that I felt fine as long as I wasn't moving. As soon as I walked or climbed I felt the lack of oxygen, but I had no symptoms of altitude sickness. This is worth looking at more closely.

I had been in Ecuador for a week or more before this, starting out in the capital of Quito, which is already at about 8,500 feet. I traveled to Riobamba, which is at about the same elevation, and left from there for the climb. The guide and I were driven up to 15,000 feet by about three the first afternoon, and hiked up the the refuge at about 16,000 feet. We left at eleven that night and after crossing miles of glaciers reached the summit just at sunrise (hardest thing I've ever done physically, but no sickness - just not enough oxygen).

We were back down to the refuge by nine and back in Riobamba a few hours later. In other words, I was only at high altitude for about twenty hours or less.

Now, the following is my speculation, and not supported by the research as far as I know, so don't take this as advice. Also, I should point out that despite the possible measures to prevent altitude related brain damage I have no intention of going above 15,000 feet again. I have a brainpower website and newsletter to maintain, after all.

My thinking is that damage takes time to occur, so if one cannot properly acclimatize to the elevation, and can't accept the obvious option (don't go), it may be best to go fast. I took sixteen hours to go from 8,500 feet to 20,700 feet - about eighteen times faster than the recommended speed of twelve days. I have not had my brain scanned, but I felt fine afterwards. I suspect (or hope) that I just wasn't up there long enough to cause any great damage.

If my speculation is correct it provides some hope for backpackers who only go high while hiking over a mountain pass, and then drop back down within a few hours. But there is another reason that many climbers go fast when at altitude: It's dangerous up there! My guide told me we had to off the glaciers by nine that morning due to falling rocks melted loose by the sun, and I heard those boulders falling!

In any case, though I am one with high climbs, I will probably still go up a few of the 14,000-foot mountains here in Colorado. But I will limit my time up there and sleep at a lower altitude. And at east now I live at 5,300 feet - a good start for avoiding altitude sickness.


The Ultralight Backpacking Site | Altitude