SpO2 levels on whitney

I'm normally 97% or whatever.

At 5300 feet elevation I started night at 88% and gradually went up to 92%. Single readings can bounce around 4% over an hour. Best to log readings all night to gert good picture.

"The low O2 levels just shocked me…not sure if that's normal."

Yes, that is very normal for Mount Whitney.

I carry a small fingertip pulse oximeter, and I record the numbers at six or more places on the way up the Whitney Trail. Then I can compare the numbers to the previous year's numbers, and I can better assess the need to speed up or slow down.

If I push really hard to the summit, I will depress the oxygen saturation to maybe 80%. More typically, it will be 85%.

Also, using the same device I monitor my pulse rate. I know what my maximum limit is, and I make sure that I stay several points below that limit.

In the old, old days, say thirty years ago, we used to push ourselves much faster going up Whitney. We would push beyond the point of getting tunnel vision, so the oxygen saturation was probably down around 70-75% back then. Not recommended.

So, here is what you do. Plot how your resting pulse rate increases with altitude. Let's say at sea level it is 60. Then at 5000 feet it is 64. Then at 10000 feet it is 68, etc. Now plot your maximum pulse rate (which takes some heavy exercise). Let's say at sea level it is 180. Then at 5000 feet it is 170. Then at 10000 feet it is 160. You get the idea. If you keep extending those curves, they will eventually intersect. That means that you can't do any more work beyond resting. That, effectively, is your altitude ceiling. For some people, that is probably 10000 feet. For others like Ed Viesturs, it is probably 30000 feet.

–B.G.–

If I read this right, 85% appears to be normal at Whitney summit elevation (4400m):

http://www.high-altitude-medicine.com/SaO2-table.html

Good data here thanks guys.
When my wife was in labor an alarm would go off whenever her, or the babies saturation dropped below 90 so I thought it might be a bad thing. Apparently climbing mt whitney and child labor are a little different. ;)

Pressure breathing and Lamaze are pretty much the same thing right? ;)

Fetal blood circulation is quite a bit different from adults.

If you are at sea level and your oxygen saturation is 98-99%, then that is normal. If you are at sea level and it drops to 90%, then something is going on. It might be from exercise stress or from illness. One person I know has the condition of COPD, and they are normally down around 80-85% at sea level. That person would likely die from the air at 10000 feet.

As you get up to higher and higher elevations, you expect to see that drift downward. However, when you get to some point around 70-80%, you will be feeling dizzy, or maybe you can just tell that your brain is slow.

The challenge for the high-altitude climber is to be able to recognize just how bad your condition is. Then, if you decide to keep going higher, your training has to kick in and keep you doing the correct things even with diminished brain power.

Sadly, for too many climbers (e.g. Into Thin Air), the desire to keep going up is still present after the ability to safely climb up has gone.

I have a test chart that you can use at high altitude. One person administers the test to the subject. You can quickly tell "how far gone" the subject is.

–B.G.–

BG, Any reference or ability to post the chart you are referring to? I would be interested. Thanks.

I'm not sure how this will print out. This is the first of two images.

1. You must print it in color.
2. Print the first image on the front of the sheet, and the second image on the back.
3. You hold it between the subject and the tester, so that the subject sees only the front, and the tester sees only the back.
4. There is no absolute score, but you can figure out how far impaired the subject is.

–B.G.–

When I print these things, I print them on A size paper. You could print them small on a card, but that would make it extra difficult for somebody whose eyesight might be a bit impaired.

The last time that we used this, the subject was so impaired from altitude that he could not get past the second line.

The test is similar to what you might use on a drunk.

–B.G.–

For myself, I know what kind of mental arithmetic I can do (say, 11^5 or 11x75x75) with difficulty, but correctly. When I can't do that, (I carry a digit and seconds later, the memory of the carried digits is just gone), I know I'm impaired. The simpler stuff I can't do, the more impaired I am. Reading the time on an upside-down analog watch is freaking difficult above 12,000 feet!

What I notice in companions is first through conversation, not by skin tone or rectal temperatures. They aren't as smart, witty, with-it or pleasant to talk to. They get conversationally lazy, dumber, and more irritably. It is similar to them getting heat-stress or hypothermia, so I need to do a differential between those, but my first clue is always that they seem like a different person.

I've long wanted to hike 20 miles at sea level, take a Mensa qualifying exam and then repeat the process but on top of Whitney. I'm pretty sure I'd lose about 20-30 IQ points at altitude.

"What I notice in companions is first through conversation, not by skin tone or rectal temperatures."

Good grief, David. If you are using rectal temperatures, then I think you are going at this altitude thing all wrong!

–B.G.–

But David has a lot more fun than you do with your color charts!

Imagine the memories……

'The test is similar to what you might use on a drunk.'
Fun test at altitude and parties.

Thank you for posting the chart BG. I'll be leaving the thermometer at home. David's comment reminds me of a question commonly asked of nursing students;
How do you tell the difference between an oral and a rectal thermometer?

Top Line – Carmine, Ivory, Azure, Sepia, Lime

Does that mean I'm drunk, or female?

Neither, Ralph. Your cultured, educated, sensitive side is showing, that's all.

You will make a great husband for some lucky cultured, educated, sensitive, and refined UL backpacking lady!

I'm still looking. Natalie Portman ticked most of those boxes, but of course I had to dump her when I discovered her base weight is 16lb.

> I know what kind of mental arithmetic I can do
And when you can't remember what mental arithmetic you should be trying to do?
:-)

Actually, hypoglycemia can have similar effects imho. Ditto hypothermia.

Cheers

That's why it is best to have the subject tested by another person.

Otherwise, it would be like depending on a drunk driver to know when he is impaired.

Since I am often peak-bagging on a solo basis, I carry the miniature pulse oximeter to do the testing work.

–B.G.–

At 58 I began using "NO2" supplement for weight lifting. It is L-Arginine tablets in time-release format. I get 'em at GNC and they ain't cheap. Now 71 I always use it above 8,000 ft.

"NO2" stands for nitric oxide, the dissolved gas in your blood. L-Arginine stimulates more production of this gas, which in turn dilates all blood vessels in the body to one degree or another.

The advantage of NO2 tablets for high altitude is that the capillaries in your lungs' alveoli are dilated allowing greater blood flow and therefore more O2 uptake. The secondary advantage is more O2 is supplied to your muscles, delaying lactic acid build-up.

Now I hear the chorus of male voices saying, "Yeah, that's why mountain climbers use Viagra and Cialis." Yep it is, but NO2 tabs are a lot less expensive, require no prescription, release over 8 hours and have a milder effect on the body. BTW, I prefer the NO2 RED formulation, not the "NO2 BLACK".

So far I've not used Diamox at altitude but so far my highest altitude has only been 12,000 ft. (about 4,000 meters)