Oxygen: Mountain High vs. Precise Flight

[M016576]

34 minutes ago, ilovecornfields said:

Seriously, though. Have you met him? He’s in great shape. I wouldn’t make any assumptions about his pulmonary physiology lest he smack you over the head with his (excellent) landing DVD.

What are these “D.V.D.’s” you speak of?  Sounds like an ancient form of video medium.  Haven’t even seen one in a decade.

I’m not making any assumptions- just stating why he probably feels better when he has a higher O2 sat.  The references I posted delve into copd... but also discuss normal o2 sats at higher altitudes (5000+’) for acclimated people.  If one isn’t feeling well, more is almost always better... unless one is hyperventilating->hypocapnia, in which case controlling rate and depth of breathing becomes more important.  But I think hypocapnia would be more difficult to induce with a cannula...Less so with a mask.

question- do you know how effective pulse oximeters are in unpressurized environments at altitude?  I have no idea, but I’m curious.

the key takeaway I have from this thread is that we all have different levels of fitness, physiology and environmental factors that make us all more or less susceptible to hypoxia, and at different rates.  So to say “everyone is A-OK at 92% and above” is probably an oversimplification of a complex issue.  That’s the point I was making in far fewer words.

 

Edited September 5, 2019 by M016576

[ilovecornfields]

9 hours ago, M016576 said:

What are these “D.V.D.’s” you speak of?  Sounds like an ancient form of video medium.  Haven’t even seen one in a decade.

I’m not making any assumptions- just stating why he probably feels better when he has a higher O2 sat.  The references I posted delve into copd... but also discuss normal o2 sats at higher altitudes (5000+’) for acclimated people.  If one isn’t feeling well, more is almost always better... unless one is hyperventilating->hypocapnia, in which case controlling rate and depth of breathing becomes more important.  But I think hypocapnia would be more difficult to induce with a cannula...Less so with a mask.

question- do you know how effective pulse oximeters are in unpressurized environments at altitude?  I have no idea, but I’m curious.

the key takeaway I have from this thread is that we all have different levels of fitness, physiology and environmental factors that make us all more or less susceptible to hypoxia, and at different rates.  So to say “everyone is A-OK at 92% and above” is probably an oversimplification of a complex issue.  That’s the point I was making in far fewer words.

 

I’m violating the rule that was suggested to me regarding having medical discussions with non-medical people on a public forum but I think there are a couple of points worth mentioning.

1. No one said “everyone is A-OK at 92% and above.” We did say that most people do well at >/= 92% and I stand by this.

2. The article you referenced was written by a nurse for people with chronic lung disease. While this is nice, we have much better resources available to us and I would like to clarify some of the points she made (sorry, but this is a complex issue and sometimes the devil is in the details).

2a. It is “normal” for your SaO2 to drop at altitude. This is true, but “normal” is not always “ideal.” It is normal for you to bleed when someone cuts your arm with a knife and normal for you to die if someone stabs you in the heart. Totally normal. Not ideal. Even though it is “normal” for our oxygen saturation to drop at altitude, this is often not “ideal” and the reason we use supplemental oxygen.

2b. She said that if you have COPD you shouldn’t titrate your oxygen level without your doctor’s permission- this is due to the hypoxic pulmonary vasoconstriction mentioned in my previous post. Mostly an issue with people with chronic lung disease, not with “healthy” aviators.

2b. She mentions CO will give falsely high SpO2 readings. Absolutely true. I would worry much more about this than the effect of altitude on the accuracy of pulse oximeter readings because even very low levels of CO will read artificially high and fool you - one of the reasons why it’s so important to have a pulse ox and CO monitor.

3. If you would like, send me a PM with your phone number and I’ll be happy to discuss this with you offline.

@carusoam, are you proud of my list?

Edited September 5, 2019 by ilovecornfields

[Hank]

3 hours ago, ilovecornfields said:

2b. She mentions CO will give falsely high SpO2 readings. Absolutely true. I would worry much more about this than the effect of altitude on the accuracy of pulse oximeter readings because even very low levels of CO will read artificially high and fool you - one of the reasons why it’s so important to have a pulse ox and CO monitor.

@carusoam, are you proud of my list?

I can't speak for Anthony, but I'm sure @DanM20C is proud of you for including CO monitors in the discussion! Go Sensorcon!

[carusoam]

Way to go, ILC!

It can be a real challenge to bring expertise to a public forum...

Especially, when the words can stay around for a good long time....  While things change.

I like the numbered list... 

Thanks for sharing the details.

PP thoughts only, not an Internet forum expert...

Best regards,

-a-

[M016576]

14 hours ago, ilovecornfields said:

If you would like, send me a PM with your phone number and I’ll be happy to discuss this with you offline.

I will- along with my questions- which primarily relate to how acclimation and age effect one’s “alertness” based on O2 sat- I’m curious primarily due to my own personal hypoxia symptoms, which I’ve noticed changing over the past 10 years during my annual trips through the chamber.

Actually- what got me to make my post were the following two posts (neither of which are mine).  And while they don’t say exactly “AOK at 92%+”, the second one says that 90-100% is within the range of noise threshold... and I mentioned why I bet it wasn’t below the noise for Don.  To which you told me I should be hit upside the head.... I have certainly made some ridiculous, silly and uninformed posts over the years deserving of such a smack, but in this case, I’m not sure it was warranted.

>>>>>>>>>>>>>>>>>>>>>>>

   On 9/4/2019 at 12:51 PM,  donkaye said: 

No matter what you say, I can definitely tell the difference between 93 and 96 and 96 is what I feel comfortable with.

If more oxygen at a given altitude makes you feel or perform better, that's the outcome you're looking for.  I would simply claim that numbers between 90-100% are within the range of "noise" and how you feel is a much better reflection of your oxygen status.

<<<<<<<<<>>><<<>>>>>>>>>>>>>

 

Edited September 6, 2019 by M016576

[Herlihy Brother]

My late ame was Henry Rowe, reportedly one of the best. He set me up with welding o2 and medical canulas--all the O2 you need and cheap as dirt, why complicate it?  Now with the a* I look back and wonder what I was doing messing w o2 in the Mooney vis a vis block times and weather...I don't believe the need is justified. iow, just powering through at 12k should get the job done within the ballpark.  Either that or go around. The times I've topped weather in

The Mooney I also  found myself praying away those downdrafts and cycle to cycle internal combustion variations.  Do the math, it's hard to save 20% fuel or time going over weather.

[gsxrpilot]

4 hours ago, Herlihy Brother said:

My late ame was Henry Rowe, reportedly one of the best. He set me up with welding o2 and medical canulas--all the O2 you need and cheap as dirt, why complicate it?  Now with the a* I look back and wonder what I was doing messing w o2 in the Mooney vis a vis block times and weather...I don't believe the need is justified. iow, just powering through at 12k should get the job done within the ballpark.  Either that or go around. The times I've topped weather in

The Mooney I also  found myself praying away those downdrafts and cycle to cycle internal combustion variations.  Do the math, it's hard to save 20% fuel or time going over weather.

1. "All the O2 you need" up to about 17K, but not nearly enough if above 18K. 
2. Not complicated at all and I get 4x the O2 time out of the bottle with the MH O2D2.
3. It's not about "toping the weather" but about more range or shorter trip times.  On a four hour trip, the difference between 12K and 24K will be more than 30 min and nearly 10 gal of fuel. 24K is often much more efficient. It's also safer in the sense that there is a much larger glide ring.

[RLCarter]

13 hours ago, Herlihy Brother said:

He set me up with welding o2

i wouldn't  use welding O2, that stuff is crap

Edited September 25, 2019 by RLCarter

[Herlihy Brother]

7 hours ago, gsxrpilot said:

1. "All the O2 you need" up to about 17K, but not nearly enough if above 18K. 
2. Not complicated at all and I get 4x the O2 time out of the bottle with the MH O2D2.
3. It's not about "toping the weather" but about more range or shorter trip times.  On a four hour trip, the difference between 12K and 24K will be more than 30 min and nearly 10 gal of fuel. 24K is often much more efficient. It's also safer in the sense that there is a much larger glide ring.

Those are great points.  My experience has been one flight every other year where I realize that 100knot tailwind at FL250 for the whole 2-4 hour trip.  More often than not, I have similar or better flight trip performance at or below 18k as I would have going higher.  My typical flight path is California to texas then either back to california or up to south dakota or chicago to washington state and back to california.  Last week I was stuck down at 15.5k for 4 hours with a 50 knot headwind because winds were even worse higher and I had to slow down to increase range to avoid a fuel stop.   Another common scenario is I leave California eastbound when there is a good weather window, meaning high pressure over the southwest, which also means a big headwind going east...I finish business in texas and come back against the prevailing westerlies which are more headwinds--so headwinds both ways and staying low (10k') both ways.   My wife says the best way to save time on a flight is to cut back the time I spend piddling around the hangar afterwards.

[neilpilot]

22 minutes ago, RLCarter said:

i would use welding O2, that stuff is crap

I also would us welding O2, but I'd like to know why you would use it if you think that "that stuff is crap". 

 

I know first hand that the one major industrial gas supplier that distributed O2 fills medical and welding cylinders from the same storage tank, on the same production line.  The only difference in a welding O2 cylinder, other than the CGA type cylinder valve, is if any residual contamination remains in the cylinder.  The fill method makes contamination unlikely.

Other than that it's exactly the same O2.

[RLCarter]

29 minutes ago, neilpilot said:

I also would us welding O2, but I'd like to know why you would use it if you think that "that stuff is crap"

It's been corrected, good catch

[EricJ]

1 hour ago, RLCarter said:

i wouldn't  use welding O2, that stuff is crap

In A&P school I learned to not use medical O2, because *that* stuff is crap for aviation use.    Apparently that's because medical O2 historically didn't require sufficiently dehydrating the charge, and if there's any moisture in it it can be Very Bad for aviation use (corrodes tanks and things, freezes in fittings, etc., etc.).

Apparently the wisdom to not use welding O2 came from those suppliers historically not having sufficient standards for oil and contaminant removal for breathing.    My understanding is that welding technology has advanced to the point that in many applications they need their O2 very clean these days, so, as mentioned, it turned out that the suppliers just generate very, very pure O2 that works for pretty much all applications.   I suspect that if you trace out the source of your FBO's "aviation breathing oxygen", it probably all comes from the same places as the welding and medical stuff.   At least, I haven't been able to find a separate source of the stuff.

[RLCarter]

58 minutes ago, EricJ said:

Apparently the wisdom to not use welding O2 came from those suppliers historically not having sufficient standards for oil and contaminant removal for breathing. 

O2 and Oil only mixes once 

[Bob_Belville]

John Deakin - Pelican’s Perch - has written about O2 - aviation, welding, medical. Ms. Google can find the article(s). Bottom line, it’s the same, at least for our purposes.


Sent from my iPad using Tapatalk

[larryb]

I would never try to justify oxygen based on fuel cost and tailwinds. I absolutely justify it on comfort. Flying for hours in nice cool smooth air is great. Flying in hot bumpy air close to the ground is not. Basically I always fly pretty high and take the winds I get. On the few occasions I try to chase the winds it does not work out. TAS goes down as I go down and the wind often does not decrease enough to make a difference.

[JohnB]

On 9/4/2019 at 11:56 AM, slowflyin said:

I had ask them about the Bravo because I had seen one of your previous post.  They recommended a small regulator between the ceiling port and their unit.  Seems to be working well.  I've got maybe 25 hours of utilization.   Is the Bravo system unique?  I assumed many models had the same altitude compensating regulator.  Maybe mine is not working properly.  How much flow do you get at sea level?    I will say that no matter what kind canula type O2 system I use my saturation can drop if I'm not cognizant of my breathing.  I tend to go into shallow breathing mode.  I've checked it at my desk (400' MSL) after a long sit at the computer and have found it below 93.   Truthfully I suspected the 39 dollar meter probably wasn't as accurate as I hoped.  If I take a slightly deeper breath my stats rise very quickly.   The wife does much better.  She never seems to fall below 93 and is normally 95 or higher.  

You sold me on the O2D2, I think I’ll need to get one of these. Do you have a part number of the small regulator between the ceiling port and their unit? If you remember who you talked to at Mountain high that might be very useful for me to get mine installed. 

[aviatoreb]

I have the o2d2 and I use it often.

I like it for many of the reasons said, saving o2 etc.

But one more reason I like it - with any other o2 system I always am not fully sure it is working and delivering o2.  How do you know if it got blocked or ran out or something.  But with the o2d2 it comes in discrete pulses every time you treat, that you can feel if it is in your nose, or you can feel and hear if it is in your o2 mask (with mic) (in fact in the mask with mic it makes you sound like Darth Vader breathing).  This is good since every breath you breath you know you are getting that good o2 stuff.

Also there is an alarm that sounds if o2 were to stop delivering.

I use oxyarm which is by far a better way in my opinion than standard cannula around your neck as with oxyarm there is no tugging on your nose when you turn your head.  Its attached to the headset.

Also another house keeping thing - I use bottles (instead of built in) o2 - and I keep my o2d2 strapped to the ceiling between the pilot seats slightly behind the  front seats and in front of the back seats.  SO o2 tubes go up from the bottles to the ceiling, and then cannula or mask tubes come down from the o2d2 unit to the pilot.  No space for tangling etc.

[slowflyin]

10 hours ago, JohnB said:

You sold me on the O2D2, I think I’ll need to get one of these. Do you have a part number of the small regulator between the ceiling port and their unit? If you remember who you talked to at Mountain high that might be very useful for me to get mine installed. 

I’m on the road.  I’ll check this afternoon. 

[donkaye, MCFI]

10 hours ago, JohnB said:

You sold me on the O2D2, I think I’ll need to get one of these. Do you have a part number of the small regulator between the ceiling port and their unit? If you remember who you talked to at Mountain high that might be very useful for me to get mine installed. 

I sent mine back for a refund.  I never could get my O2 saturation level above 92%, even on the highest setting. (I want at least 96%).   That was unsatisfactory for me, but apparently not for others.  Also,  in contrast to others, I didn't like the constant sound of breathing in my ears.  It was very disruptive.

 

[slowflyin]

15 hours ago, JohnB said:

You sold me on the O2D2, I think I’ll need to get one of these. Do you have a part number of the small regulator between the ceiling port and their unit? If you remember who you talked to at Mountain high that might be very useful for me to get mine installed. 

I bought the kit.  EDS-O2D2-2G   O2D2 with STR Stabilizing Regulator.   Not sure who I spoke with but if you give them a ring I'm sure they can confirm.  Mine needed the Scott connector.  

[donkaye, MCFI]

10 minutes ago, slowflyin said:

I bought the kit.  EDS-O2D2-2G   O2D2 with STR Stabilizing Regulator.   Not sure who I spoke with but if you give them a ring I'm sure they can confirm.  Mine needed the Scott connector.  

I had the stabilizing regulator.  It didn't work in my airplane, which is also an M20M like John's.  It was hooked in series with the altitude compensating regular that comes with the airplane and created the problem according the the people at Mountain High.  I don't know how other people make this work with their altitude compensating regulator unless they are satisfied with an O2 saturation level of 92%.  At the highest level of oxygen flow I don't 'think there is that much of a savings over the mustache canulas, but I don't have a scientific basis to say that.

[larryb]

Don:

 

I was wondering if your problems stem from a flow restricted orfice in the cabin port. My system is tapped into the aircraft after the altitude compensating regulator but before any restricted fittings.

 

From:

 

https://www.mhoxygen.com/2016/wp-content/uploads/O2D1-D2-Maint-Questions-2012md.pdf

 

 

Additionally, we have seen many situations where customers connect the EDS unit(s) to the connectors and tubing that came with their aircraft, then plug them into the high pressure outlets in the aircraft. This has caused a lot of confusing problems because these connectors generally have flow restriction orifices. In many cases this has allowed the EDS unit(s) to check out okay at ground level when the pulse response is low, but then activate with flow fault alarms at higher cruising altitudes. Additionally, this problem can be difficult to reproduce because the EDS unit(s) operate with pressure altitude and not barometrical corrected altitude.

 

 

 

 

[kmyfm20s]

Does anyone fly with an Aerox mask below 18K to keep their O2 up? I am another one that needs to actively breath to keep my saturation levels up. I was thinking when I fly in the mid teens this would help. Im going to first try this wearable pulse oximeter that I ordered which has a vibrating alarm. You can set your alarm limit via the app and monitor yourself as well. 

https://www.viatomtech.com/sleep-o2

[JohnB]

On 9/26/2019 at 2:00 PM, donkaye said:

I had the stabilizing regulator.  It didn't work in my airplane, which is also an M20M like John's.  It was hooked in series with the altitude compensating regular that comes with the airplane and created the problem according the the people at Mountain High.  I don't know how other people make this work with their altitude compensating regulator unless they are satisfied with an O2 saturation level of 92%.  At the highest level of oxygen flow I don't 'think there is that much of a savings over the mustache canulas, but I don't have a scientific basis to say that.

Hmm looks like I’ll have to research this a bit more before jumping in to a purchase. Or perhaps figure out how to do my own oxygen from my shared hangar. Hmmm 

[aviatoreb]

On 9/27/2019 at 7:45 AM, kmyfm20s said:

Does anyone fly with an Aerox mask below 18K to keep their O2 up? I am another one that needs to actively breath to keep my saturation levels up. I was thinking when I fly in the mid teens this would help. Im going to first try this wearable pulse oximeter that I ordered which has a vibrating alarm. You can set your alarm limit via the app and monitor yourself as well. 

https://www.viatomtech.com/sleep-o2

That looks like a terrific device.

Yes sometimes if its a long flight or there are any weather issues, I might run a mask when planning 15, 16 or 17 so I don't need to be fiddling with switching o2 delivery devices if I want to climb for some reason.