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Anyone with Aviation Physiology Knowledge?

I have discovered that my first (observable) symptom of hypoxia is that... I get pissed off!

I looked it up and this appears to be what the medical folks usually describe as "restlessness or anxiety." But I would call it irritability.

So if you start getting peeved while flying, check that O2!!

I must live in a constant state of hypoxia these days! :D
 
That sounds more like CPAP, or maybe BIPAP, than PEEP. I can’t think of a practical way of delivering PEEP in a non-intubated patient.

Key word in my description was "effectively" - I wasn't trying to explain to medical folks but to non-medical. In the medical setting, the problem is with bad lungs but in military high altitude setting the problem is different - healthy lungs are a given.
 
Key word in my description was "effectively" - I wasn't trying to explain to medical folks but to non-medical. In the medical setting, the problem is with bad lungs but in military high altitude setting the problem is different - healthy lungs are a given.

I am utterly confident that you understand ventilation/oxygenation, and probably better than I do. Sorry, didn't mean to imply otherwise.
 
I must live in a constant state of hypoxia these days! :D

That's a good one!

Anyone know if an apple watch or other wearable is helpful as an oximeter? The fingertip model of oximeter I have requires a bit of care and attention to get a good reading. I think it would be nice to have a device that is constantly monitoring oxygen saturation and alerting if it goes too low.
 
That's a good one!

Anyone know if an apple watch or other wearable is helpful as an oximeter? The fingertip model of oximeter I have requires a bit of care and attention to get a good reading. I think it would be nice to have a device that is constantly monitoring oxygen saturation and alerting if it goes too low.

Louise has a Garmin watch that does (allegedly) pulse oximetry - but it is wildly off from the readings we consistently get from the three fingertip units we have, even when done at the exact same time. Bottom line - I don’t trust the watch reading at all.

Paul
 
Teacher

I would like to submit that this is a Master Class in how to create a fascinating and valuable conversation in today's online environment. Colonel Wawrzynski presented an interesting dilemma which likely concerns us all, supported it with facts and evidence, garnered supportive input and comments from a whole slew of community experts, stayed out of the way of the discussion except to keep it on track, and then, seemed to bring it to a logical and simple conclusion which we can all understand and find helpful.

I'm not looking for a positive reply from Mr. Wasrzynski (we've done that already) but man...if I ever get a chance to sit through one of his lectures - I'm there!

Bravo
This community Rocks!
 
Louise has a Garmin watch that does (allegedly) pulse oximetry - but it is wildly off from the readings we consistently get from the three fingertip units we have, even when done at the exact same time. Bottom line - I don’t trust the watch reading at all.

Paul

Current version of the Apple Watch has a pulse oximetry function. Much of the time I can get it to register SpO2 with reasonable accuracy if I sit still with my wrist elevated on a table for 10-12 seconds. As a practical matter for use while, say, piloting an airplane, it's a completely useless feature. Much better off with a $30 Chinese import from Amazon.
 
CO & oximeter

A pulse oximeter works well to give a relative indication for needing OX but remember that in regard to carbon monoxide it works in reverse. So a good CO
Detector is necessary.
Because the oximeter uses a light beam and CO makes blood brighter the oximeter will give a false indication if CO is present
 
Great thread

Pulse oximeters will measure combined total of oxyhemoglobin (O2-Hb, the precious stuff) and carboxyhemoglobin (CO-Hb, the worthless stuff) and erroneously report that total as the oxyhemoglobin % on the display, which misleads you by the amount of CO-Hb present. It is very deceptive.

CO binds to hemoglobin far more readily than O2 does, and doesn't let go nearly as easily either, effectively taking hemoglobin molecules offline until they slowly "detox" at a later time when CO exposure has ended. The silent killer needs to be respected.
 
Since this is a safety discussion, perhaps the topic of Carbon Monoxide deserves a discussion all its own. That would be about the critical importance of early detection, symptoms, etc. And detection devices and their testing, maintenance etc.

The entire discussion of pulse oximetry in this thread, up to these last few posts pointing out the issues with oximetry and CO, is predicated on the assumption that CO is not in the picture.

Having treated many victims of CO toxicity as an emergency physician, the insidious risk it poses cannot be understated. The question of smoking came up earlier in this discussion - it's an important part of the CO discussion itself since smokers (thankfully rare in the GA pilot population in my experience) can have substantial levels of carboxyhemogobin (hemoglobin bound to CO instead of oxygen) which may be insignificant on the ground but problematic at relatively low altitudes above baseline. (and may be masked by oximetry readings since CO bound hemoglobin shows as "saturated").

But of course the highest risk of CO toxicity in aviation is leaking exhaust into the cabin. Again a separate topic.
 
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Dr. Billingsley is correct.

As I read this discussion I am reminded that my $200 CO monitor is sitting on my desk simply because I wasn't happy with its look in the place where I sticky-taped it to my fancy carbon fiber panel. It seemed very out of place. That vanity could cost me if I don't rectify it. An aircraft that doesn't ingress CO during phase one could start doing so at any time due to an exhaust pipe perforation.

I've treated a few CO victims who only had nagging headaches, and did fine. I've also lost a patient family who didn't survive their vacation in a cabin with a defective gas hot water heater.
 
CO Detectors

We did this thread about a month ago, was it two? Certainly worthy of a rehash. I have gone through a couple electronic units and also keep a fresh plastic dot visible. Lots of folks beat up the little dot pretty badly and I just couldn't see why. Ostensibly according to the manufacturer's data, the card will display when exposed to varying concentrations before we should have significant symptoms. Not reliant on electricity, shockproof, surge proof, and cheap! As a backup I really couldn't see why that indicator was so maligned. Someday I would enjoy that discussion again.
 
Been following this thread. I do not remember reading about anyone suggesting the FAA PROTE (Reduced Oxygen Training Enclosure) [I do not know what the 'P' stands for.]

Before COVID, the FAA had their mobile chamber traveling around the country and one could sign up for it when it was in the area. I was living in PA when they were at KAGC and able to take advantage. I took part in the FREE FAA training.

People are different and one can have different response when deprived of O2. I learned that my hands start shaking when I am deprived of O2. Your response may be different. I do not scuba dive but I understand that they do something similar with divers when they train to dive to different depths.

Back in 2002, I also took an FAA Physiological Training Course at Oshkosh AirVenture 2002 and have a little blue card that says I completed the "Academics Only" part of the Physiological Training.

When I lived out west, I would tend to operate above 9,500 MSL a lot. I carried oxygen (IF I did not have smoke oil on board) and would tend to use O2 above 9,500 if I was going to be flying more than one leg. The use of O2 made flying all day much less fatiguing at the end of the day.

Now that I live back east, I find it rare for me to get the airplane above 7,500 MSL. My O2 tank is 3/4 full. At the present time, I would need a hydrostatic test of my O2 tank to get it refilled.
 
Herniated diaphragm

In 1980 I experienced emergency surgery at Loring AFB hospital for a herniated diaphragm where part of my greater omentum, spleen and stomach moved through the hernia into my chest collapsing my left lung and pushing my heart to one side. To say I was in deep s*** is an understatement. When they initially started the surgery they assumed the breathing problem was a pneumothorax of the lung but quickly discovered a much greater problem (this was before MRIs and CT scans were widely available).

Needless to say I was very lucky to have a talented young thoracic surgeon available at this remote location’s hospital who saved my life. However one of the residual outcomes is an elevated left diaphragm which today reduces my oxygen intake. (PS the USAF after six months recovery sent me to the altitude chamber for a thorough checkout (very scary day given the recent experience) and subsequently returned me to flight status.)

The oximeter is my friend! However if I ever saw 95% or above at any altitude I’d have a massive celebration. Normal O2 level for me is around 92 - 93%. I like to fly above 8,500’ when going cross country therefore anytime I get 9,500’ or above I breakout the cannulas and start sucking.

As been pointed out several times in this thread we all have different O2 comfort levels and techniques for various reasons. One interesting sidebar, my wife will get a slight headache if she’s above 9,500’ for 30 minutes or more so another reason to suck oxygen and her O2 levels are always higher than mine.

Fly safe.
 
We did this thread about a month ago, was it two? Certainly worthy of a rehash. I have gone through a couple electronic units and also keep a fresh plastic dot visible. Lots of folks beat up the little dot pretty badly and I just couldn't see why. Ostensibly according to the manufacturer's data, the card will display when exposed to varying concentrations before we should have significant symptoms. Not reliant on electricity, shockproof, surge proof, and cheap! As a backup I really couldn't see why that indicator was so maligned. Someday I would enjoy that discussion again.

Indeed we did: https://vansairforce.net/community/showthread.php?t=203048

I recommend we divert CO discussions to THAT thread in the interest of not hijacking THIS thread. Both are great discussions.
 
Based in Durango, CO my normal field-level Spo% is ~94%. I always use O2 above 7000 ft and periodically check Spo inflight with a pulse oximeter. I adjust my Mountain High O2 system to maintain Spo at 94% at cruise altitudes (typically 9,500 to 14,500 ft). The Mountain High O2 system is exceptionally frugal with O2…a bottle of O2 lasts for months. I use an O2 boom mounted off my Lightspeed headset.
 
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