Monitoring Oxygen Uptake

[Nyal Williams]

I went through the AF high-altitude chamber several years ago. One of
the things they demonstrated was loss of color vision with oxygen
deprivation. For those of you who are gurus, would it not be a useful
indicator to have a small color wheel mounted on the panel near the ASI
or Vario as something to scan for safety at high altitude? I'm a
flatlander and don't usually fly above 7K msl. I'm headed for high
country and I wonder about this device. My concern is whether color
vision loss means one is too far gone for this to be a practical tool
for monitoring.

[Mike the Strike]

>From years of high-altitude glider flying, I have found my first
symptom is spots and patterns in my vision. It used to occur above
about 12,000 feet AGL, but now I'm older I see the symptoms at 10,000
or even below. I have never experienced loss of color vision. I
suppose it's possible that symptoms vary between individuals.

I routinely use oxygen above 10,000 feet these days. It's cheap
enough.

Mike

Nyal Williams wrote:
...snip.. My concern is whether color
> vision loss means one is too far gone for this to be a practical tool
> for monitoring.

[Nyal Williams]

I'll be on metered oxygen, beginning at 5000K with
the Mountain High metering device. It should cover
most eventualities -- kinks in line, weak battery,
mouth breathing (which I tend to do), etc.

I'm just wondering if color vision is a useful indicator.
Everyone in the chamber noted the color loss; they
had a color wheel on the wall and called our attention
to it. I just have no idea how far gone we were; half
the class had masks off and the others were watching
behavior, and then we reversed situations.


At 19:00 13 June 2005, Mike The Strike wrote:

>>From years of high-altitude glider flying, I have found
>>my first
>symptom is spots and patterns in my vision. It used
>to occur above
>about 12,000 feet AGL, but now I'm older I see the
>symptoms at 10,000
>or even below. I have never experienced loss of color
>vision. I
>suppose it's possible that symptoms vary between individuals.
>
>I routinely use oxygen above 10,000 feet these days.
> It's cheap
>enough.
>
>Mike
>
>Nyal Williams wrote:
>...snip.. My concern is whether color
>> vision loss means one is too far gone for this to
>>be a practical tool
>> for monitoring.
>
>

[Brian]

When they demonstrated the color wheel to me it was under rather low
light conditions and it wasn't the loss of vision that was apparent but
rather how much it improved when we started using the Oxygen. It was
like someone had just turned up the lights when we turned on the
Oxygen.

I noticed my 1st symptom was the loss of my periphial(sp) vision. i.e.
my vision narrowed.

You probably saw the same or simlar video that they showed us of the
guy reading cards off the top of the deck. After about a minute or less
at 35K feet his mind sort of went into neutral and he correctly read
the 2 of spades off the top of the deck but every card after that he
called a 2 of spades no matter what it was. His motor skills were fine
He could pick up the card and look at it but the only thing he saw was
a 2 of spades.

I noticed on the quiz they gave us at 25K feet that toward the end of
the quiz my answers started repeating I had written down earlier in the
quiz and the answers didn't really apply to the question I was
answering.

Brian

[[email protected]]

NO, not useful. You will not notice your loss of accuity.

Key is to monitor O2 systems for proper functioning.

If you feel better with an objective, third-party measure, buy a pulse
oximeter.

OC

[Kilo Charlie]

The only way to assure yourself of adequate oxygen delivery to your body is
to use a pulse oximeter as OC has pointed out. There is a large variability
in how pilots react to hypoxemia. You may have color loss as a first sign
but it is not reliable.

You should also realize that even reading and interpreting the pulse ox
results could be affected once you are hypoxemic so as Mike Stringfellow
said it is cheap insurance and should be used if there is even a question.
As I've stated before, if you plan to fly at high altitudes on a regular
basis I would consider a pulse oximeter an instrument as necessary as an
altimeter. It is not perfect though and so having and maintaining a quality
oxygen system is another must. That would include some type of "bailout
bottle" as a backup if you fly wave a lot.

Casey Lenox, MD
KC
Phoenix

[Nyal Williams]

At 03:12 14 June 2005, Kilo Charlie wrote:
>The only way to assure yourself of adequate oxygen
>delivery to your body is
>to use a pulse oximeter as OC has pointed out. There
>is a large variability
>in how pilots react to hypoxemia. You may have color
>loss as a first sign
>but it is not reliable.
>
>You should also realize that even reading and interpreting
>the pulse ox
>results could be affected once you are hypoxemic so
>as Mike Stringfellow
>said it is cheap insurance and should be used if there
>is even a question.
>As I've stated before, if you plan to fly at high altitudes
>on a regular
>basis I would consider a pulse oximeter an instrument
>as necessary as an
>altimeter. It is not perfect though and so having
>and maintaining a quality
>oxygen system is another must. That would include
>some type of 'bailout
>bottle' as a backup if you fly wave a lot.
>
>Casey Lenox, MD
>KC
>Phoenix
>
Thanks for the comments. I have an excellent system
and an oximeter in hand. I will not go above 18K
in any event, and in all probability won't reach that.

[soarski]

On the other Hand ........I live and take off at 8000 ft. now also
going on OX at 14000 ft, used to fly without, at higher altitudes. The
Rules, 12500 and 14000 ft are a good measure and most likely have some
margin built in.

I do have a pulse oximimeter, which I would recomend. For you as peace
of mind. Otherwise one could worry so much about this OX thing that one
gets into hyperventilating. I have seen that on ski slopes! Those
people think they are ox starved and start breathing like crazy and get
sick that way. Also going on ox at 5000 ft, you might be out of it when
you really get up there and need it.

BTW, I have taken the oximeter on high altitude hikes and stuck it on
different older people. There I have seen guys with a 78% readout
happiely hiking along. What I like to know
is, what the low % limit is. When would one pass out?

[Bill Daniels]

"soarski" > wrote in message
oups.com...
> On the other Hand ........I live and take off at 8000 ft. now also
> going on OX at 14000 ft, used to fly without, at higher altitudes. The
> Rules, 12500 and 14000 ft are a good measure and most likely have some
> margin built in.

As near as I can determine, these altitudes were determined during WWII
using very fit 18 year olds. Out of shape geezers should lower them
considerably. Being in the later category, I set the EDS to start O2 flow
at ground level especially with difficult to handle expensive gliders. With
the EDS consumption isn't a problem.
>
> I do have a pulse oximimeter, which I would recomend. For you as peace
> of mind. Otherwise one could worry so much about this OX thing that one
> gets into hyperventilating. I have seen that on ski slopes! Those
> people think they are ox starved and start breathing like crazy and get
> sick that way. Also going on ox at 5000 ft, you might be out of it when
> you really get up there and need it.

Hyperventilating is a real problem. A "set and forget" system like EDS
helps.
>
> BTW, I have taken the oximeter on high altitude hikes and stuck it on
> different older people. There I have seen guys with a 78% readout
> happiely hiking along. What I like to know
> is, what the low % limit is. When would one pass out?
>
I've seen pilots at 80% SpO2 who said they felt WONDERFUL. They kept
repeating that over and over but they couldn't fly worth a damn. They would
look at the oximeter and claim they felt better at 80% and ask to turn the
O2 down. Is hypoxia addictive?

There seems to be a consensus that cognitive abilities diminish measurably
in the low 90's. O2 is cheap. Use it.

Bill Daniels

[Shawn]

Bill Daniels wrote:
> "soarski" > wrote in message
> oups.com...
>
>>On the other Hand ........I live and take off at 8000 ft. now also
>>going on OX at 14000 ft, used to fly without, at higher altitudes. The
>>Rules, 12500 and 14000 ft are a good measure and most likely have some
>>margin built in.
>
>
> As near as I can determine, these altitudes were determined during WWII
> using very fit 18 year olds. Out of shape geezers should lower them
> considerably. Being in the later category, I set the EDS to start O2 flow
> at ground level especially with difficult to handle expensive gliders. With
> the EDS consumption isn't a problem.
>
>>I do have a pulse oximimeter, which I would recomend. For you as peace
>>of mind. Otherwise one could worry so much about this OX thing that one
>>gets into hyperventilating. I have seen that on ski slopes! Those
>>people think they are ox starved and start breathing like crazy and get
>>sick that way. Also going on ox at 5000 ft, you might be out of it when
>>you really get up there and need it.
>
>
> Hyperventilating is a real problem. A "set and forget" system like EDS
> helps.
>
>>BTW, I have taken the oximeter on high altitude hikes and stuck it on
>>different older people. There I have seen guys with a 78% readout
>>happiely hiking along. What I like to know
>>is, what the low % limit is. When would one pass out?
>>
>
> I've seen pilots at 80% SpO2 who said they felt WONDERFUL. They kept
> repeating that over and over but they couldn't fly worth a damn. They would
> look at the oximeter and claim they felt better at 80% and ask to turn the
> O2 down. Is hypoxia addictive?
>
> There seems to be a consensus that cognitive abilities diminish measurably
> in the low 90's. O2 is cheap. Use it.

Well that explains it. My normal saturation is about 96% (in Salida).
If I type too fast my sat's gotta drop below 93. :-)

Shawn

[Eric Greenwell]

Bill Daniels wrote:
> "soarski" > wrote in message
> oups.com...
>
>>On the other Hand ........I live and take off at 8000 ft. now also
>>going on OX at 14000 ft, used to fly without, at higher altitudes. The
>>Rules, 12500 and 14000 ft are a good measure and most likely have some
>>margin built in.
>
>
> As near as I can determine, these altitudes were determined during WWII
> using very fit 18 year olds. Out of shape geezers should lower them
> considerably. Being in the later category, I set the EDS to start O2 flow
> at ground level especially with difficult to handle expensive gliders. With
> the EDS consumption isn't a problem.

I recently got an oximeter, and was surprised to see my saturation drop
to 90 and lower above 11,000'. I now set my EDS for ground level
actuation, and put it on at 10,000'. Even with that, it will stay in the
93-94% range, unless I breathe a little more deeply than I tend to. That
will push it up to 97-98%. Oxygen is cheap, and very little is used in
the 10K to 12K range anyway.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

[Andy Blackburn]

At 03:12 14 June 2005, Kilo Charlie wrote:
>The only way to assure yourself of adequate oxygen
>delivery to your body is
>to use a pulse oximeter as OC has pointed out.

I highly recommend a pulse oximeter. I wore one in
the wave last week to check out my EDS system. I had
the EDS set to the standard O2 delivery starting at
10k. At 18k I put on the oximeter - it read 79% under
normal nasal breathing. With accelerated breathing
I could get it up to 89%.

This week I tried the F15 setting (extra O2 volume).
I went from 84% to 92% in about a minute at 16k.

Under none of these flights did I notice anything unusual
in my perceptions or performance - but then again you're
not supposed to.

9B