Upon hearing the beck and call of the mountains, many a lowlander has been known to offer a quick response. The lure of skiing in Colorado or trekking the Himalayas holds the promise of unique excitement for sea level city dwellers. Yet lest you be hasty in your travel plans, it behooves you to consider the hazards of high altitude. A trip to High Country need not be dangerous, if rigorous precautions are taken.
How High is High?
Altitude is described by the following scale:
High:
8,000-12,000 feet
Very
High: 12,000-18,000 feet
Extremely
High: Above 18,000feet
As of yet, no study has been conclusive as to what factors
influence a person’s susceptibility to altitude sickness. Men and women of all
ages and levels of fitness may or may not be susceptible. To further complicate
matters you may take one trip and have no symptoms, than return at a different
time and get considerably ill. While most people can travel to 8,000 feet
without problem, if you rarely travel above sea level, it’s best to be prudent in
your preparations.
All I Need is the Air That I Breath
At sea level, oxygen concentration is at approximately 21%
and barometric pressure is at 760mmHG. With the increase in altitude, oxygen
concentration is unchanged, but the number of oxygen molecules per breath is
significantly reduced. This is due to the fact that at 12,000 feet, barometric
pressure is only 483mmHG, thereby giving even the most enthusiastic skier or
hiker 40% fewer oxygen molecules per breath. To properly oxygenate the body,
your breathing rate must increase. The added ventilation increase oxygen
content in the blood, but not to the same concentration it was at sea level.
Unfortunately, whatever activity you are participating in
will still require the same amount of oxygen, but your body must adjust to
having less of it. High altitude can also cause fluid to leak from the
capillaries, which in turn can cause fluid build up in the brain and lungs.