I've heard that too, you could spend a lifetime at altitude and within a week at sea level it's like you were never up there.
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I've heard that too, you could spend a lifetime at altitude and within a week at sea level it's like you were never up there.
Still living at 7,000 feet I haven't noticed the acclimation wain, even when I lived at hood river, OR for a summer. When I got home I felt fine.
Never had a problem with altitude. It's true that it can strike anyone at any time, I've had very fit friends be crippled by it. Highest I've been is 19,500-ish and highest I've slept is 15k. Hydration is key. Also, eating is important because some people get slightly nauseous and don't want to eat anything, and some fatigue can be related to bonking. Didn't sleep well at 15k but it probably had as much to do with gnarly winds trying to tear my tent apart than it did altitude.
Bingo, this happened to me in Alaska. Highest I've ever been was 20,3-ish. Had to sleep at 17 for four nights due to weather, was not in good shape after that. Had a pretty good case of AMS. Going down from 17,000 to 14,000 was the hardest day of that whole trip for me, way more than summit day even.Quote:
Originally posted by homerjay
Also, eating is important because some people get slightly nauseous and don't want to eat anything
Note to self: acclimatize better next time, keep eating and drinking. I forgot those last time.
I read in an USFS pamphlet that oxygen in the air is 55% as dense at 8K compared to sea level.
My question is how much per 1k does the oxygen density decrease??
Some members of my group were fucking dying when we hiked to the Billboard at Silverton. They were experiencing much more than "billboard delirium." I believe the altitude was @ 13,100.
The following link is to a nice review article in the NEJM. You ought to be able to get on with out problem, if not PM me and I can send the article as an attachment:
http://content.nejm.org/cgi/content/full/345/2/107
In my grad school physiology class, I recall John West (probably the world's preeminent high altitute physiologist) saying that barometric pressure can affect athletic performance at higher altitudes. I don't remember at what heights the onset of this phenomenon occured, however, but it's tempting to posit that, perhaps, the occasional high altitude sickness we experience may be due to prevailing climate/weather patterns.
Edit- BTW, John West had fleas in his house.
I remember hearing somewhere that the worst cases of AMS in Summit County (CO) were seen in young athletic people who had just returned from visits home. After spending a week on the East Coast, or Florida, or wherever, they would get home, and immediately join their friends in some sort of activity. Since they were in good shape and previously acclimated, they didn't think to take it easy for a few days, and the result was AMS.
Got my ass-kicked up at Silverton on our last trip there, I had been working in Phoenix (1,500ft) for the past month and then went directly to Silverton, drove up the night before and skied the next day.
I didn't really do too bad until the late afternoon climbing Tiger Claw, definitely blowing a lot harder than I have been before. The month of being away from Durango (6,680), had definitely taken it's toll.
I stayed pretty well hydrated and had been eating throughout the day but just wasn't breathing at a rythym of any sort. First time I can remember any altitude related problems, I've never been above 15K but haven't had problems before either.
Atmospheric Pressure
Put Mt. Everest (28 deg North) at the latitude of Mt. McKinley (63 deg North) in the United States and it is likely that no climber would ever have been able to reach the summit breathing the natural air. Everest would feel, physiologically, as if it were an additional 3,000 feet higher. The air would be so thin that even the best climber would have no choice but to use supplemental oxygen. Why? Because of the many factors which affect atmospheric pressure.
Pioneering scientists discovered atmospheric pressure (also known as barometric or air pressure) in the 17th century, and determined a startling new fact -- that air actually has weight. Evangelista Torricelli, one of the first to discover atmospheric pressure, once said, "We live submerged at the bottom of an ocean of the element air." The Earth's gravitational field is pulling on air, and this pull, or "pressure" of air, is called atmospheric pressure. Toriccelli also went on to develop the mercury barometer, an instrument used to measure atmospheric pressure.
A barometer also monitors variations in atmospheric pressure. As air becomes thinner, the density of air decreases, and so too does the pressure of air. Many different factors affect the density of air. Most measurably, as altitude increases, air becomes less dense, decreasing atmospheric pressure. Standard altitude-pressure tables allow mountaineers and aviators to determine their approximate height by measuring atmospheric pressure. This relationship also works inversely. The height of a mountain determines, approximately, the density of air on its summit. As air becomes less dense, it contains less gases per unit of volume, and therefore less oxygen. Physiologists use this information to predict the oxygen deprivation a mountaineer faces at high altitude.
For the most part, this relationship works quite well. But factors other than altitude also effect the density of air. For one thing, water molecules have less mass than other gas molecules in air; so as water vapor increases, the density of air decreases. Temperature also changes the density of air. As air gets warmer it expands and becomes less dense, causing atmospheric pressure to fall.
In addition, air within the atmosphere can rise and fall, changing the atmospheric pressure. In fact, meteorologists monitor atmospheric pressure at the Earth's surface in order to determine whether the pressure is rising or falling, which helps to predict weather patterns. High pressure often represents stable air, while low pressure can signify instability. On a cold, sunny day there will be a significantly higher atmospheric pressure than when a big storm is moving in on a hot and humid day.
But the density of the atmosphere varies at different points around the globe as well. At the poles, the atmosphere is much thinner than at the equator. Because of these variations, two mountaineers climbing at the same altitude but on different mountains could experience different atmospheric pressures and therefore different physiological effects. One climber might have no trouble breathing, while the other can barely pull in enough oxygen to survive. The small amount of oxygen on the top of Everest puts this peak near if not at human's physiological limit. And this is why Everest, if it were at a higher latitude, could very well be beyond the physiological limits of someone trying to climb without oxygen.
Only one direct measurement of atmospheric pressure has ever been made on the summit of Mt. Everest, in 1981. The present expedition has a small hand-held barometer and we hope it may be possible for them to make the second measurement.
What Kellie said and, in addition, barometric pressure will also, to an extent, affect gas exchange at the level of the lung alveoli- the lung's gas-exchange structures.
I got beat down by AMS when I returned to Alta (8,500) after spending a week in Michigan (sea level).
I remember it was the worst headache of my entire life, and scrip-strength Ibuprofen barely made a dent.
Even Sherpas or Andean Indians living in the Altiplano? You gotta wonder, those dudes are freakish.Quote:
Originally posted by Kellie
Atmospheric Pressure
Put Mt. Everest (28 deg North) at the latitude of Mt. McKinley (63 deg North) in the United States and it is likely that no climber would ever have been able to reach the summit breathing the natural air. Everest would feel, physiologically, as if it were an additional 3,000 feet higher. The air would be so thin that even the best climber would have no choice but to use supplemental oxygen.
Luckily it takes longer...Would be a tuff job trying to acclimatize for higher climbs, where you might wait for a weather window for days or weeks.Quote:
Originally posted by flykdog
I've read that it only takes about 2-3 days to de-acclimatize(sp).
Full acclimatisation (when the bonemarrow?has made "enough" hemoglobine takes usually 2-3 weeks. After that hemoglobine values dont increase. The bloods hemoglobin stays up for its lifespan, witch is 1-2 weeks if i remember correctly.
And you have to remember that above 5500m human system doesnt actively acclimatize anymore. Instead it starts to "eat itself up", a combined cause of salt balance/dehydration/nutrion/etc shtikk.
And quote:"I've heard that too, you could spend a lifetime at altitude and within a week at sea level it's like you were never up there." is mainly true...
Exept for some peruvian and ethiopian societies that have lived for generations high enough that they´r physiology have adapted for the altitude. But, it has more to do with their capacity to manage the bicarbonate levels in their blood, not only higher hemoglobin values.
But im not a doctor...
PS. And using Diamox might be helpfull (to certain extent) for sealevel people that go bumpin´n grinding and dont have enough time to acclimatize properly. You usa people can get it quite easily, eh?
yep. I've never used it, but I've climbed with people who had Diamox, and they seemed to like what it did for them.
Working as a backcountry ranger last summer, I happened upon a group of people who, when they saw me, said something along the lines of "Thank God you are here" and went on to tell me about a member of their party (age 20-25ish) who was experiencing HAPE.
They took me to where he was sitting-- out in the sun on the shore of a lake (elev 10,200ish ft). It was tshirt and shorts weather but he was going into shock and was shivering, even while wearing pants, long sleeves, and a heavy jacket.
His breathing was labored; he occasionally wheezed out spittle from his lungs. It took two men to help him stand up and move him twenty feet so the helicopter could have a safe place to land.
The day before, his group has decided to go fishing at a nearby lake but, feeling sick, he stuck around camp. His conditions worsened overnight and by the morning I came across him, he was in pretty poor shape.
His father made mention that he had had problems with altitude sickness before, but never this bad. He and his group ignored many, many signs that shouted to him "GO DOWN, FAST!"
The helicopter picked him up shortly thereafter, and after a brief stay at the local medical clinic (15 miles down the trail and 60 miles by road had they attemped to get him down and drive) at 7200 ft, he was flown to Salt Lake City for further care.
As far as I know, he ended up being OK. I felt horrible for him, but what really affected me was his father. He was staying under control but obviously very shaken. I can't imagine what he was feeling as he hiked out and headed to the local clinic. Probably the longest 15 miles of his life.
If you or a member of your party even have the suspicion that something like this is occurring, make sure you drink plenty of water... and get down, quickly. It's not worth taking the chance and waiting to see if you're just feeling a little woozy or if you're really in bad shape. 10,200 ft, to me, is a pretty low elevation. His group came from SLC, so the elevation gain they had experienced wasn't huge.
KEEP HYDRATED
I got e-coli food poisoning (in Mojave) and was hospitalized in Mammoth. I dehydrated so quickly and completely that I was given SIX liters of fluid via IV. They told me that it was unheard of for a person my size to take in that much fluid. I was close to dead, apparently, and it had something to do with the combination poisoning and altitude.
My uncle is a gastro-enterologist and asked me some key questions before sending me to the hospital (one lovely side effect of food poisoning is that you lose all rational thought, you think you're not as sick as you are), one was that he had me look at the tips of my fingers and tell him if they were pruned (like if you're in a jacuzzi too long), which meant I was overly dehydrated.
A ski instructor friend told me that if you're not peeing every 45 min- hour, then you're dehydrated. Pisses off my friends who I ride/ski with, that I'm always stopping to pee.
I think Spamhelmet and AntiSoKalSkier have covered deacclimation on the dot.
There isn't a lot of good data on this stuff.
The biggest thing is prevention. The easiest way to do that is to limit the rate of ascent. One rule of thumb I saw is no more than 1,000 ft climb a day above 8,000 ft. People who are more fit tend to get high-altitude illnesses more because they ascend the mountains faster.
The main treatment for all high-altitude illnesses is GO LOWER.
As for medication, acetazolamide (Diamox) and steroids have been useful in acute mountain sickness (AMS). For high-altitude pulmonary edema (HAPE), if you can't get down right away, nifedipine has been shown to be of some benefit. Supplemental oxygen is important too. Salmeterol and nifedipine have been used for prevention of HAPE. High-altitude cerebral edema (HACE) is considered a medical emergency, and one should descend as quickly as possible.
One more thing--although there's a lot of recommendations about aggressive hydration, no one has ever studied if aggressive hydration is actually beneficial. It's something to think about, especially since the main prevention and treatment for AMS is a diuretic (i.e., acetazolamide). Although I wouldn't recommend that someone become dehydrated at altitude, drinking enough so that you pee every half-hour may not be the best thing for prevention of high-altitude illnesses.
When I was sixteen I hiked Mona Loa on Hawaii. For those who don't know it's the flatter mountain on the big island thats about 14K. Slept at sea level for previous week, then hiked it in one day got to the crater at 2 or 3 in the after noon. By the time we got there I only had a headache but it was the worst pain I've felt in my life. Every step felt like my head exploded. Maybe drank 32oz the entire trip in the dry broken lava fields (we only hiked the last 3K or so but it was a long trail.) Drank some water when we got back to the trail head and I was good to go. That's the only time I have ever felt it and have been to 14K many times. H2O makes the d.
The hike was good and even though it was cloudy, below you could see forever in all directions. If anyone is ever in Hawaii, I would highly recomend it.
I've never heard voiding every 45min-1hr as "normal." In fact, if you were urinating that often, I would be concerned (diabetes is the first thing that comes to mind). The frequency isn't important when it comes to hydration, but rather the total output and quality of the urine.Quote:
Originally Posted by yogachik
unfortunatly, most of my time at altitude is pushing thru the low ams levels. that is because i get behind on my water consumption from the start, which causes loss of appetite and eventually apathy to the point where you really stop and think things over. this past week i reached 9+ on your scale while doing box elder. i tried to pace my water consumption because of the length of the tour but that worked against me. before i knew it i had gone 5 hrs @ 50-60 degree temps with only 10oz missing from my pack. it completely screwed me on the final summit approach and i shut down. i drank all i could but i couldn't get the drive to eat again. long story short, i've taken a page out of trackheads book and got a 3L nalgene bladder. my kidneys, stomach, lungs and head like me much more now.
edit: lan, every hour on a strenuous hike sounds right to me. i'll check the books later tonight.
Diamox is a diuretic and will make you pee frequently, also making you get dehydrated quicker. I stopped taking it on the only trip I've done up high because of this. I didn't seem to have any disadvantage over the other people on the trip who continued taking it.
I watched someone develope HAPE at about 18000 after a push up to 20000 that day. It was scary to watch a super fit mt guide quickly become almost helpless, halucinating, pulse about 120, about 16-18 breaths a min and coughing alot. I was sharing a tent with her and we decended first thing in the morning. She was alot better the already the next day after 24h at 14000.
That trip was more about enduring miserable conditions than enjoying being on the mountain.
I suffer terribly from the less recognized problem of low altitude cerebral edema, commonly called LACE. Symptoms--induced by too much time in the flatlands--are irritibility, restlessness, lack of focus, looping "Yearbook" on DVD, and obsessively driving by ski shops that aren't on the way home. If this happens to you, immediately go to high altitude, descend as quickly as possible, and repeat. (The life you save may be your own.)
A climber/doctor explained to me an increase in pee frequency and volume at altitude is a positive sign your body is acclimatizing well, compared to you drinking the same amount of water at sea level. I have been fortunate to not need diamox the few times I've been around 6000m, and have definitely noticed an increase in peeing (freq and vol) not related to how much water I'm drinking. Frigging crazy, actually. I need to get a bigger piss bottle, as I regularly fill a liter in one shot at high(er) altitudes.Quote:
Originally Posted by LAN
To add to Monica's note, there is also the lesser known HAFE. High Altitude Flatulance Expulsion. Anyone who has ever slept in a tent at altitude probably knows what I am talking about. I dont have proof from medical studies, but I am sure it is real.
On the serious side, I have experimented quite a bit with elevation and have had both positive and negative experiences.
Negative: climbing in Ecuador, my buddy and I hung out in Quito (10,000 ft) for a month getting ready, and during that time climbed to 14k, 15k, 16k (even sleeping at 14k one night). Then we went and climbed Cotopaxi (19K), and I felt great, but my buddy felt like death. So we finished and headed back to Quito for two nights. I talked him into still going up to Chimborazo(20k) (but he was seriously reluctant), and so after two nights back at 10k we headed up. On Chimbo Jeff felt great, and I felt like death (reading Kellie's scale, I am guessing a 6). I seriously wanted to quit at a false summit 19,800, with the 20k summit in view (just didnt care). Being attached by rope to my buddy was the only thing keeping my feet moving. Anyhow, made the summit, and made it down, but then just curled up in a little ball and didnt feel right for about 10 hours after getting off the mtn. It sucked....like the worst flu I have ever had, just whole body (and insides) feeling shakey.
Positive: After that I was fairly altitude paranoid, so on a trip to Nepal, I went by the book (a conservative book at that). On my way up to Gokyo (15k) (one valley over from Everest base camp), I followed the instructions in my book which said; "over 12k only ascend 1000 feet per day, and every 3000 feet stay an extra night". So, went 12,13,14 (stayed 2 nights), then up to Goyko at 15. The first morning in Gokyo, at 4am, I climbed to 18k (Gokyo Ri) to take picts of the Sunrise over Everest....and felt great. So, good that I did the hike again at 4PM, and took sunset pictures (cool experience, being alone on a 18k peak at 8PM, and decending with headlamp). Anyhow, there were tons of trekkers in Gokyo who were sick as dogs, just lying in bed all day.....was happy with my conservative approach.
So, what is my summary of this......dont really know; altitude is crazy, can hit when you dont expect, fitness doesnt really matter, but taking it slower than you think you should can only help.
Sidenote: we had a guide in Ecuador, and he asked us if we smoked. We didnt and he was disappointed.....said that his smoker clients tend to have less altitude problems. Dont know the medical backing behind this, but thought it interesting....I guess their bodies are used to having less O2.