Well, funny thing about having professors who are graduates of Cambridge, Cal Tech, and (most impressively in my opinion) a New Zealand university -- they happen to know literally everything. So you can't get away with anything.
Dr. Blakey quickly corrected me and let me know that oxidative damage is not an effect of acute altitude sickness; in fact, oxidative damage doesn't set in until a person is at an extremely high altitude for an extremely long period of time. Everything I talked about in my blog is way far down the road from the common headache and dizziness that are associated with acute altitude sickness. My bad everyone!
The real cause of acute altitude sickness starts with the fact that the lack of oxygen at high altitude causes you to breathe faster, so you actually begin hyperventilating. This increase in flow of air into your lungs results in an excess expulsion of CO2. The level of CO2 in your blood begins to drop, causing your blood to become more basic (since CO2 is an acid gas). This process of increased blood pH due to increased respiration is called alkalosis, since the blood becomes more alkaline, or more acidic. You start to feel dizzy and fatigued, your head hurts, you feel nauseous, etc.
Your kidneys correct for this problem by removing bicarbonate ions (HCO3-) from the blood. This compensates for the loss of CO2. The normal reaction in the kidneys is below:
CO2 + H2O <-----> H2CO3 <-----> H+ + HCO3-
(carbonic acid) (bicarbonate ion)
A reduced level of bicarbonate causes the H+ ions in the kidneys to be released into the bloodstream, so the blood is no longer basic. Unfortunately, the kidneys can only respond but so fast, so it takes a few days before they start excreting the bicarbonate ions. A drug called Diamox, or generically known as acetazolamide, can be taken to force the kidneys to excrete biocarbonate ions faster than normal.
Diamox
This drug is a carbonic anhydrase inhibitor. Carbonic acid is a catalyst that speeds up the reaction of H2CO3 to CO2 and H2O -- the reverse of the first reaction above. When Diamox inhibits carbonic acid, there is a build-up of H2CO3 and thus a build-up of bicarbonate (remember Le Chatlier?). So those bicarbonate ions that are no longer reacting will be excreted from the kidneys. The excess H+ ions are absorbed into the bloodstream to make the blood more acidic, thus stimulating ventilation and increasing the level of oxygen in the blood.
Hopefully my explanation of the chemistry of acute altitude sickness is correct this time. And if not, I'm giving up and blogging about something else instead.
http://www.altitude.org/home.php
http://en.wikipedia.org/wiki/Acetazolamide
http://jap.physiology.org/content/102/4/1313.full.pdf+html
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