Thursday, February 20, 2014

Altitude Sickness

I don’t know about you, but I’m an air breather.

My favorite air has plenty of oxygen in it, because that’s what feeds every cell in my body. As much as I like oxygen-rich air, I also like to go way up high in the mountains, where the air is thin. That’s okay, as long as I do it the right way, but if I mess up I can fall victim to altitude sickness.

Under the right conditions, everybody is vulnerable to altitude sickness. It isn’t a matter of how old you are (except that young children tend to be at increased risk). It doesn’t matter how many muscles you have. It doesn’t matter that you have been up high in the mountains in the past and never had a problem. It doesn’t matter that you’re an excellent hiker. Actually, it’s even possible for altitude sickness to strike a person riding in a vehicle.

This condition we call altitude sickness is the way the body responds when it is suddenly subjected to a low-oxygen environment. It’s the “suddenly” part that’s most important. Acclimatization to high altitude is a slow process. The problem is that most of us don’t take the time to do it right. We want to be at the top of the mountain right now, so off we go. And that’s when problems strike.

In a nutshell, altitude sickness results from going too high too fast. Approximately 20% of those ascending from sea level to 8000 feet in less than one day develop some form of altitude sickness. The laws of physiology dictate that the higher the elevation, the longer it takes to reach full acclimatization. Above 10,000 feet, about 75% of people feel some symptoms. Those who have suffered altitude sickness in the past are slightly more at risk of recurrence.

But if you gain altitude slowly, gradually acclimatizing over a period of time, you may never experience an altitude-related medical problem. Ascending beyond 8000 feet should be done at a rate of no more than 1500 feet per day. And here’s a rule that will assist the body to acclimatize — after reaching altitude, avoid strenuous exertion for a period of 24 to 36 hours.

But here’s another problem — At high altitude, the air is not only thin and oxygen-poor, it is also very dry. This makes it especially important to drink more water that you are accustomed to at lower elevation. As you exert yourself at high altitude the tendency is to over-breathe the exceptionally dry air, and this accelerates dehydration. As dehydration increases, blood volume is reduced, and that intensifies altitude sickness. So it’s kind of a wicked spiral, one thing feeding off of the other.

So if you have any plans to go to the mountains, make sure you take it easy until you become acclimatized. It’s just one of the rules of survival for us air breathers.

1 comment:

  1. Don't recall ever going over 8000 feet other than in airplanes.