[pct-l] elevation sickness

[scourtway at bpa-arch.com (Steve Courtway)]

It's interesting that science still does not have a definitive answer as to
why some folks are more suseptible to AMS and the effects of elevation in
general.  I routinely climb mt. san gorgonio (11,500 ft.) starting here in
San Diego (elev. 0) the same morning with no problem, I've never even got a
headache.  Other friends though, have been reduced to whimpering messes with
those types of gains in the past.

I'm not sure the 1000 ft. per day rule applies here in California, heh
heh.......

s.c.


----- Original Message -----
From: "Rod Belshee" <rbelshee@hotmail.com>
To: <pct-l@mailman.backcountry.net>
Sent: Monday, March 21, 2005 3:07 PM
Subject: Re: [pct-l] elevation sickness


> I hiked in the Himalayas in 2003 (www.trailjournals.com/annapurnacircuit )
> and
> attended an excellent seminar on AMS in Manang, Nepal. Here's the basics
> from that seminar, followed by more detail.
>
> Only a few decades ago, about 10% of mountain trekers in Nepal died from
> AMS(!), but that has declined to near zero now. Acute Mountain Sickness
> (AMS, or elevation sickness) is now easily avoided with a bit of
knowledge.
>
> First, here's the most important rules:
> -- gain elevation slowly, 1000 feet per day
> -- hike high, sleep low
> -- stop gaining at the first signs of AMS, drop elevation if signs remain
> (headache, tiredness, dizzy, nausea, out of breath)
> -- descend immediately if severe signs occur (pounding headache, unable to
> walk a straight line, unable to regain breath, coughing fluids...)
> -- avoid the temptation to "not hold up the group" and keep going
> -- medications as prophylactics are very controversial
> -- watch for both dehydration and AMS, as they are intertwined
>
> Elevations in Nepal are considerably higher than anything encountered on
the
> PCT. We crossed Thoroung La Pass at 17,500 feet, and looked upward to the
> mountains from there! At 14,491 Mt Whitney is much less of a concern. For
> most PCT through hikers the natural profile climbing up from Kenedy
Meadows
> takes care of you automatically, with little special planning. I describe
a
> typical PCT hiking profile at the end of this message.
>
> Here's more detail on each of the main AMS points:
>
> Gain elevation slowly
> -- begin limiting gain and monitoring for AMS at about 9000 feet
> -- while a few people experience symptoms lower than that, 9000 feet is
> generally conservative
> -- gain about 1000 feet a day (some other sources say 1500 feet per day)
> -- every fourth day, take a break with no elevation gain
> -- do not assume that your are immune if you have not had AMS in previous
> climbs
>
> Hike high, sleep low
> -- the 1000 foot daily limit applies to sleeping elevation
> -- It is good to hike even several thousand feet higher during the day and
> descend for sleep
> -- Until you are acclimated, plan your hike profile and camp sites
> accordingly
>
> Signs of AMS
> -- AMS is pressure-endused endema of the lungs or brain
> -- The warning signs are related to the brain and the lungs
> -- Brain (early signs):  headache, loss of appetite, tiredness, weak,
dizzy,
> nausea, difficulty sleeping, ...
> -- Lungs (early signs):  out of breath after just a few steps, ...
> -- Brain (final signs): severe pounding headache, vomiting, cannot walk a
> straight line, double vision, changes in behavior, ...
> -- Lungs: (final signs): coughing (especially blood), out of breath even
> after you stop, ...
>
> Stop or descend
> -- at first early signs, stop and observe the symptoms, and drink lots of
> water
> -- if they worsen at all, descend immediately
> -- if they do not clear in a few hours, descend
> -- descend until symptoms begin to abate, which often happens in just
> 500-1000 feet
> -- typically it is recommended to descend to the elevation of the prior
> nights sleep or lower
> -- rest 1-3 days, drinking lots of water, before resuming the climb
> -- if symptoms are severe, then death may occur within hours, so descend
> completely and get to a hospital
>
> Groups and denial
> -- using the 1000 feet per day profile, only 10% of people will have
> symptoms
> -- in groups, simple arithmetic dictates a higher chance that at least one
> member will have symptoms
> -- in groups, no one want to slow others down, so the pressure is high to
> keep pushing
> -- a group of four people has a 41% chance of someone developing symptoms
> -- a group of six is more likely to have at least one person develop
> symptoms than not!
>
> Medications
> -- Diamox is sold to prevent AMS, but prophylatic use is very
controversial
> and not recommended
> -- Diamox speeds up the respriatory system which can mask early symptoms
> resulting in a more severe case of AMS
> -- Diamox is very useful to for symptomatic relief after onset and during
> descent
> -- Diamox can never substitute for descent, which is the only cure
>
> Dehydration
> -- Drinking lots of water before and during the hike seems to reduce the
> likelihood of AMS onset
> -- Drinking lots of water is recommended for rest days after AMS onset
> -- Symptoms of dehydration and AMS overlap, so always treat for
dehydration
> when AMS is suspected
>
> PCT climbing profile
>
> A typical northbound PCT hike first reaches 9000 feet in the Sierras at
the
> Olancha
> Pass Trail cutoff (67.5 miles into section G). Camp in this area, or push
> over the 10,500 saddle (71.1) to camp back down at 9000 feet near the
> creek before Gomez Meadows (74.8) or at Death Canyon creek (77.2). Either
> way the next day crest at 10,700 before descending to camp around 10,000
> feet near one of the two springs (82.4, 84.0), or Dutch Meadow (88.9), or
> hike out to Trail Pass campground (91.2). You have now hiked high and
slept
> low, and gained 1000 feet per day. You are now acclimated to camp the next
> night at 11,000 which virtually opens up the whole section.
>
> I don't know of anyone who hiked from Kennedy Meadows and developed AMS,
but
> it in 2004 one hiker hitchhiked from Kennedy Meadows (6000 feet) to
> Horseshow Meadows to climb directly up to Trail Pass 10,500, and developed
> serious AMS.
>
> Whitney
> Before the Mt Whitney ascent, most hikers camp near Crabtree Ranger
Station
> (10,640) but some hike up to Guitar Lake (11,480) to make it even easier.
A
> few other 2004 hikers spent the night on Whitney to watch the sunrise,
which
> exceeds these guidelines and was cold, but they loved it! Remember, these
> are just guidelines! They will generally keep you safe with minimal
> knowledge about AMS. If you chose to overnight on Whitney, memorize the
AMS
> signs to watch for, pair up with another hiker or two, be ready and
willing
> to descend in the dark if necessary, and then sit back and enjoy the
> sunrise!
>
> And as a final cross-cultural message, another AMS tidbit from the
Nepalese
> guides: eat
> garlic soup the morning of your highest climb.
>
> Steady (Sr)
>
>
> -----Original Message-----
> From: pct-l-bounces@mailman.backcountry.net
> [mailto:pct-l-bounces@mailman.backcountry.net] On Behalf Of Dustin
Prickett
> Sent: Saturday, March 19, 2005 9:17 AM
> To: pct-l@mailman.backcountry.net
> Subject: [pct-l] elevatoin sickness
>
> Elevation sickness, is it a factor for someone who is not used to it and
> goes straight up to Whitney?  What is the best way to prevent it, what are
> some early the symptoms?  Dustin
>
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