Outdoor Action Guide to High Altitude: Acclimatization

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sambieni
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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by sambieni » Sun Aug 06, 2017 3:50 pm

Interesting question on what to do...
Last year I was at 1000 Islands Lake, solo. I was all tucked away in tent early from exhausting hiking day. Any rate around 10 pm I woke up to folks outside my tent who complained an older woman in their group felt ill/off from altitude. Admittedly, I was not a group member so not 100% up on all details, but an hour of this going on outside my tent, I gathered what seemed relevant details It sounded like she was mostly just not drinking fluids, eating much, and just really spent from the day. She sounded really drained from what I gather. Could not hear symptoms of headache, but tehy kept saying it was altitude. They spent an hour sorting out a plan and gathering food from nearby campsite. She was talking and no fluid sounds, no slurred speech, just seemingly exhaustion. By 11 pm they set off back towards Agnew Meadows.

My gut - she sounded spent and simply in need of fluids and rest more than anything as opposed to a night hike out.

I know scenarios all vary, but best to just go down in dark or try and rest and head out at daylight?








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rightstar76
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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by rightstar76 » Mon Aug 07, 2017 7:39 am

It all depends on how serious the situation really is. It might be much more dangerous to hike at night in a panic exhausted than to rest and reassess at first light. Someone could have had an accident hiking in the dark and not necessarily the person with altitude issues. If she was worse in the morning, the group would have been rested enough to safely hike out or get help.

In the past, whenever I've had altitude symptoms, they've been mild. I've always felt better after a nap or a good night's rest. Acetaminophen helps too. I've been lucky. Thanks to discussions like these on HST, I know what to do if the symptoms don't go away and get worse. Time to get off the mountain.

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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by gdurkee » Mon Aug 07, 2017 8:41 am

Going out at night: "it depends" is right. A lot of variables and there's no right answer. I'd tend towards probably not. It might, though, make sense to send someone out to get help or find a camper with a SPOT, sat phone etc. The counter argument is that symptoms get so bad at night that walking out in the morning is impossible (probably because of time to develop and lying down, spreading fluid throughout lungs making breathing even more difficult). If it's HAPE, though, you need a medivac. Only consider walking if it's all downhill and you don't have to gain significant elevation to get out.

The real problem, of course, is evaluating and distinguishing between AMS and HAPE or HACE. They're very, very different in physiology and I'm not clear on whether they're on a continuum, though sometimes described that way. I'm not sure that's a useful way to think of them. With AMS, you just feel bad -- nausea, headache some lassitude. Fluids and food (if possible) help quite a bit. Again, HAPE is a serious problem breathing and, as a result, affects being able to travel and, significantly, It gets progressively worse over 6 - 12 hours where AMS should be getting better. I think the best you can do is pay close attention to how someone's doing, especially on Day 2 and 3. That's the time to descend when it's possible. To confuse things even more, I've seen cases where the party camps at the bottom of canyons (~9,000'), goes over passes then back to a canyon bottom. The person has low-level HAPE for awhile then, camping at altitude (11,000+) they get rapidly worse. So I think what might look like AMS symptoms still happening by day 3 is a cause for serious concern.

As a side note, if you're in the Crabtree/Whitney area, the RS there has a Gamow bag and that's been used successfully to keep someone alive at night for medivac in the morning. The bag can be pressurized with a foot pump to effectively lower altitude. A pain for ranger and crew, but it does work. I think Sequoia Kings has another one at the heliport that can be dropped if there's no LZ nearby.

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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by Jimr » Mon Aug 07, 2017 9:59 am

As a side note, if you're in the Crabtree/Whitney area, the RS there has a Gamow bag and that's been used successfully to keep someone alive at night for medivac in the morning. The bag can be pressurized with a foot pump to effectively lower altitude.
Interesting. A low pressure hyperberic chamber.
If you don't want to be eaten, don't look like food.

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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by rlown » Sun Oct 01, 2017 4:19 pm

Ok.. I was on the Metoprolol and Lisinopril for the first part of my 9/25-9/29 trip. Couldn't get the BP or heart rate up for normal backpacking. First day, I made it 3.6 miles, never sweated or was able to get a heart rate up enough to ascend. Sucked. Second day, I didn't take them, but the drugs were still on board. I could go about 40 minutes and the granite would fluoresce white, the snow was unbearable to look at, and the yellow grass turned bright green. Next came not being able to see the needles on a pine tree. Pack immediately came off and I laid down, as the next step in that is vision draining from your head and that fall to either hit your head on a rock or break a fishing rod. That part didn't happen because I recognized the progression.

Came to a personal conclusion/decision as I hung out in the high meadow below Vogelsang. I'm done with the drugs. I could live a long life as a flat lander, or get off the drugs so my body would work normally ascending a trail. Yes, I'm telling my doctor, and she'll say "you might have a stroke." I decided I've seen and done a lot and I intend to keep doing it, and If I stroke out on a high trail, I'll be totally content.

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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by gdurkee » Mon Oct 02, 2017 10:10 am

Whoa! That would be pretty frightening... . Though, just looking up Metoprolol in addition to bradycardia, under rare side effects: disturbed color perception. Weird to have it triggered by altitude though. I store stuff like this away so, if you learn something after talking to doc, it would be great if you posted or TM'd.

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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by rlown » Mon Oct 02, 2017 10:19 am

Pretty sure it was the Lisinopril that triggered the symptoms (limits BP) Couldn't get blood to the brain. When I was on the full dose of Lisinopril, I fainted 3 times at home (tile floors are hard on the tailbone and skull.) I cut the dosage in half by splitting the pill in half and it was tolerable.

Still done being a pharmaceutical guinea pig for doctors reading from the big book of drugs. I can read as well. :)

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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by SSSdave » Mon Oct 02, 2017 11:27 am

Thanks for the thread, rlown, a subject we all need to periodically review because it is complex with potential serious life threatening consequences.

Despite living like most of us near sea level, because of my decades of Sierra Nevada backpacking and skiing, I seem to be fine going up to timberline elevations without bothering to acclimate. However one may still have a threshold elevation not far above what seems fine. Several years ago on a cold windy October day, two of us drove up from sea level to the Patriarch Grove in the White Mountains at 12k where I exhausted myself by hiking about chasing sunset light. Then during the evening developed a horrible headache that lasted most of the night. The next day recovered and subsequent days were fine. But it taught me a lesson that my body is not immune to such dangers.

More commonly during winter are effects going up for a day of skiing at 8k to 10k altitudes about Tahoe. On first day's, I'm usually fine skiing most slopes however as soon as I move onto mogul slopes where the energy level to maintain is like running sprints, oxygen deficiency often rapidly catches up with me. A day or two later that will not be the case. Then if I go back home at sea level for a work week before returning, that next first day will have similar effects. But the longer the time between skiing trips the more likely first day oxygen effects as my body transitions per the article.

David

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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by longri » Tue Oct 03, 2017 11:42 am

Above 10,000 feet (3,000 meters) most people experience a periodic breathing during sleep known as Cheyne-Stokes Respirations.
Interesting to me to see that they say most people experience Cheyne-Stokes breathing. While I've witnessed it happening to companions very few of them are aware of it when asked about it in the morning.

For me Cheyne-Stokes breathing sometimes becomes severe enough that I can't sleep very well as I repeatedly wake up gasping. Usually all I need to do is to take 125mg of Acetazolamide (Diamox) and my breathing becomes normal in 30-40 minutes. The weird thing that I've never understood is that this never happens on my first night at altitude. It only occurs after being out for 2-5 days, typically about 4 days. So a weekend trip where I sleep at 13K I'm fine. But on a week long trip I might have this happen at 10K (sometimes lower) on the fourth night.

Since it takes a while for Diamox to have an effect, it is advisable to start taking it 24 hours before you go to altitude and continue for at least five days at higher altitude.
That recommendation is for someone wanting to avoid AMS. But for C-S breathing, in my experience the drug is in my bloodstream and having an effect in about half an hour or so. According to the literature, peak plasma levels occur 1-3 hours after taking a tablet.

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Re: Outdoor Action Guide to High Altitude: Acclimatization

Post by mrphil » Wed Oct 04, 2017 5:01 pm

I'll put in my vote for Diamox (acetazolamide). We were in Peru last August and one of our party had acute AMS symptoms beginning at 12k. We went down to Cusco, grabbed a few blister packs of acetazolamida and some coca leaves for tea, gave him 24 hours to get it into his system, went to 14k, then went to just under 20k without any problems at all. Brought a lot of pills back, but the tea was disgusting without something to sweeten it, and isn't legal to bring back anyhow, although I understand you can get some sort of better tasting, but still effective version of it on Amazon that's "decocainized" (but you will supposedly still test positive for the drug) https://www.amazon.com/coca-leaf-tea-ba ... B019O4JRN8

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