allitude sickness

I had this thread saved and am glad to see it revisited. I especially would like to highlight and concur with Bob's subtly noted strategy, which I consider essential for higher altitude travel:

"I had been recording my vital signs all the way along…"

With or without Diamox, this is a key habit to develop and employ.

With no special equipment Bob can only monitor 2 of 4 vital signs, pulse and respiratory rate, both of which seem to go up on me when I am climbing hills ; ).

The easiest vital signs to measure are rest pulse rate and respiration rate. Granted, these vary during a day of heavy hiking. I would take vital signs each morning immediately after waking, while I was relaxed and warm in the bag. Things start jumping around when you walk around in cold air. Also, some days I would take vital signs late in the evening, but there wasn't great consistency. I knew my altitude at each camp, so I could graph out my progress with rest pulse rate primarily.

Each person has a rest pulse rate, maybe 50-70 per minute at sea level. Then each has a maximal rate. If you don't know your own maximal rate, the approximation is 220 minus your age. Several factors will vary that. A cardiologist determines some of this on a treadmill test. As you get higher and higher in elevation, your maximal rate will steadily decrease, and your rest rate will steadily increase. If your current vital signs suddenly "blow the curve," you might be in trouble.

If you live at sea level, graph 0 elevation and your rest rate. Now go up to 5000 or 10,000 feet, sleep overnight, and then do a morning rest pulse measurement. Graph that. Continue upward toward your high elevation goal, and keep repeating the measurements in camp and graph it all. After a while, you should have your own little graph of your own expected rest rate for each camp elevation.

At some point, your elevated rest rate has gotten pretty close to your reduced maximal rate. We will call that your "ceiling" (to use an aviation term). From that elevated rest rate, you can hardly begin to do any exercise, and then you've already hit your reduced maximal rate. You are incapable of going any higher without fainting or something equally sinister. For a lot of people, this magic number is about 120 rest rate. Some people call it 110. YMMV.

Often, if a person has been pushing too hard uphill, or if they are getting into a high altitude pulmonary edema situation, they will show this 110-120 diagnostic, and that is the time for the warning lights to start flashing. Obviously the pulse will go high while you are still exercising and going up over a high pass, and it may not recover too quickly if you are seriously tired after reaching camp. Measure it when you feel recovered. If edema is setting in, it might not show for some hours.

Your respiration rate should recover in camp, but if it stays elevated or becomes noisy, this could be a real concern. If you haven't recovered by morning, then your hiking buddies need to consider escorting you down the mountain immediately. The rule of thumb is that if the victim is taken down 3000 feet, a life has been saved. It is smart to walk out before you are incapacitated, because helicopter evacuation might be impossible.

I check my own progress against my own graph, and as long as everything stays predictably normal, I do not fool around with Diamox or anything like that. Early in a trip, if I had seen my own progress declining, then I would consider Diamox as early as possible, because it takes it a couple of days to really kick in. If you wait until you are at virtual collapse and then start Diamox, you might do more harm than good.

It is especially hard to take Diamox if you have severe chronic dehydration. Diamox plays all sorts of games with your body's water balance, and you see increased thirst, increased urination, or other temporary abnormalities.

I like to do these graphs as part of a mental exercise for high elevation. If I can't do the math, I'm probably already at my ceiling.
–B.G.–

Everything you ingest, inhale or exhale, even put on your skin, can have an effect on your body, most do in fact.

The idea of "drug" is a man-made distinction. Every food that you eat or drink causes body chemistry, and even mental variation, no matter how minute.

It's too bad social stigma, has such broad reaching implications sometime.. Some of the items mentioned here can have much worse physiological consequences than a natural solution used for countless generations by the Incas and other Andean travelers.

Like they say in Peru: "La Hoja de Coca, no es Droga."

Which is absolutely true, as it's about as closely related to the stigmatized chemically processed end result, as whatever the base chemicals in any pharmaceutical are to the final pill.

*sigh*

Heh, sorry, just a chip on my shoulder. Nobody seemed to mention the south american altitude cure.

A little off topic, I guess, and my apologies if it seems nit-picky. The reason some may care is if they try to keep their heart rate to a percentage of HRmax or of HRreserve:

> If you don't know your own maximal rate, the approximation is 220 minus your age.

This formula is not that accurate, and is less accurate for fit people (which I presume many BPL folks, especially those going to high altitude, are). One simple formula that is closer is (205 – age/2). There are others that claim to be even closer.

FWIW: just yesterday in the gym my heart rate was 6 bpm over what "220 – age" would predict, and I was not pushing hard enough to be at or about my maximum.

— MV

My cardiologist told me that, for my age, I was lucky to have any vital signs to measure.
–B.G.–