Oximetery testing

[jskinner]

Does anyone know what criteria is used to suspect sleep apnea when looking at over night oximetery data? How many desaturations are need to be seen and at what levels?

Now that I have a recording oximeter I have been testing all my family and friends.

[ItRme]

I've considered a oximeter because I spent time in the hospital with pneumonia. Also, my oxygen level was real low. Perhaps I can keep up with it using an oximeter. I will watch this one

[NeedinZs]

For the 2 cents this is worth..... a DME co. rep. once told me below 90, using an overnight pulse ox machine.
She did not say anything about duration.

Coincidently, I did a one night pulse O2 test before I had my actual sleep study. That particular night, I only got to 90 and not below.

I still had my suspicions, and later did a 3 night at home sleep study.
My O2 on those 3 nights averaged around 85, and showed OSA.

So I'd say if someone registered borderline, they should probably do more than one night with a pulse O2 machine.

I wish I had an oximeter, I have a few relatives I would LOVE to loan it to, for a little convincing!

[Guest205]

They wouldn't release from hospital until it was stable at 90+

[mindy]

Mine dropped to 85% which they told me was "mild" desaturation but with my heart problems, they definitely wanted me on CPAP.

Mindy

[NiceDMEDude]

Hi everyone,

Most pulmonologists feel that nocturnal oximetry is a fairly poor indicator of OSA. This is because an otherwise healthy (lung-wise) person may desaturate very little, if at all, and still have mild or moderate sleep apnea.

Generally speaking though, people who have severe OSA (AHI>30) do have significant oxygen desaturations while sleeping.

IMHO, pulse oximetry is a useful tool, but should not be used to decide whether or not to have a sleep study. That decision should be made based on how you feel after a full night of sleep, does your sleep partner tell you that you stop breathing, do you awaken gasping, have hypertension, etc.

A lot of docs use oximetry to verify, after using XPAP for 1-2 weeks, that your oxygen levels are acceptable while using XPAP. If they are still low, that may indicate a need for supplemental oxygen bled into the XPAP.

jskinner, have you had any success with the family members you have loaned your oximeter to? Have any shown low sats and then gone for a sleep study? Kudos to you if you help convince them to get treatment!

One of the best uses for oximetry I have ever heard is to show a person who desaturated during a sleep study their lowest oxygen levels. Then hook them up to the oximeter while they are awake and have them hold their breath as long as possible. After about 40-50 seconds, they can't hold their breath any longer, but usually they still have a sat of 91-92%. This is pretty convincing! A client told me that a doctor at Stanford (probably the most respected sleep center in the country) used this tactic on him and it really opened his eyes!

P.S. Please don't sue me if someone keels over trying this at home

[jskinner]

IMHO, pulse oximetry is a useful tool, but should not be used to decide whether or not to have a sleep study.

Oh I agree completely. Its just when you are trying to convince someone that they should go for a study you need all the ammo that you can get.

jskinner, have you had any success with the family members you have loaned your oximeter to? Have any shown low sats and then gone for a sleep study?

Not so far. Dispite what I have been though my parents seem to think snoring is something funny and don't take seem to take it seriously.

Last night for example I tested my mom. She had 23 desaturations with a low of 81%. Clearly 81 is not good but its not clear to me how to know if the overall picture was bad. My mom has had hypertension recently and they have been having trouble getting it under control so I wondered if sleep apnea could be a factor.

Here are her stats:

Time with SpO2<90: 1:01:28, 16.8%
Time with SpO2<80: 0:00:00, 0.0%
Time with SpO2<70: 0:00:00, 0.0%
Time with SpO2<60: 0:00:00, 0.0%
Time with SpO2<88: 0:43:32, 11.9%

Time with SpO2 =>90: 5:03:28, 83.2%
Time with SpO2=>80 & <90: 1:01:28, 16.8%
Time with SpO2=>70 & <80: 0:00:00, 0.0%
Time with SpO2=>60 & <70: 0:00:00, 0.0%

> 0 & <10 seconds: 2
=>10 & <20 seconds: 4
=>20 & <30 seconds: 4
=>30 & <40 seconds: 3
=>40 & <50 seconds: 1
=>50 & <60 seconds: 0
=>60 seconds: 9

> 0 seconds: 23
=>10 seconds: 21
=>20 seconds: 17
=>30 seconds: 13
=>40 seconds: 10
=>50 seconds: 9
=>60 seconds: 9

I'm going to test her again sometime and try to get her to sleep on her back. I might note that my diagnoses sleep study showed a low of 83% and I have severe sleep apnea (AHI 55)

[ablong]

James I read with intrest your comments about the pluse ox.
I became very attached to one inthe hosptial a couple of years
back when sleep apena like to have taken me out right in
front of the staff eyes. I had no idea I had sleep apena and
neither did they. I found it was life line with a loud voice
when my o2 level fell under 85 percent. I now sleep with some kind
of xpap like it was grown to me. The sleep DR sends a small Nonin
out for a couple of days because my o2 falls off inmy sleep even
when on xpap. Ihave purchased a Nonin 2500a and Profox software
which I use Once or twice a month. I can add up to 2Liters of o2 to the
cpap machine to hold up my o2 level above 90%.

Here is a couple of art I wish you would read
go to aeromedix.com look for a art written by Mike Bush and Dr. Blue
There is a disclaimer for they sell Pulse Ox machines but he has a
tale which comes close to what happen to me in the hosptial with
sleep apena.

Also be aware the machine can be fooled I was in Lung Dr office and
his nurse had a nonin 3100 wrist mod on my arm and she reached down
and told me to relax my hand because i was cutting off blood flow
to my wrist and making machine give a false reading. I sometimes think I do this in my sleep making me look worse than I am.

There are some good used units on the internet. (cheep)

Any way lots of Luck expermenting with the new toy.

Allen

[stevoreno]

[quote="ablong"]James I read with intrest your comments about the pluse ox.
I became very attached to one inthe hosptial a couple of years
back when sleep apena like to have taken me out right in
front of the staff eyes. I had no idea I had sleep apena and
neither did they. I found it was life line with a loud voice
when my o2 level fell under 85 percent. I now sleep with some kind
of xpap like it was grown to me. The sleep DR sends a small Nonin
out for a couple of days because my o2 falls off inmy sleep even
when on xpap. Ihave purchased a Nonin 2500a and Profox software
which I use Once or twice a month. I can add up to 2Liters of o2 to the
cpap machine to hold up my o2 level above 90%.

Here is a couple of art I wish you would read
go to aeromedix.com look for a art written by Mike Bush and Dr. Blue
There is a disclaimer for they sell Pulse Ox machines but he has a
tale which comes close to what happen to me in the hosptial with
sleep apena.

Also be aware the machine can be fooled I was in Lung Dr office and
his nurse had a nonin 3100 wrist mod on my arm and she reached down
and told me to relax my hand because i was cutting off blood flow
to my wrist and making machine give a false reading. I sometimes think I do this in my sleep making me look worse than I am.

There are some good used units on the internet. (cheep)

Any way lots of Luck expermenting with the new toy.

Allen

[Snoredog]

<89% is the number where it comes medically significant.

[NiceDMEDude]

jskinner, wow, your mother absolutely should take note of those readings.

If someone spends 11.9% of their sleep time with a SaO2 less than 88%, it is definitely valid. Occasionally you see a blip where someone desats severely, but the total amount of time with a low sat should be taken seriously. Movement during the night can cause brief artifact where the sat dips, but 43:32 indicates a legitimate problem.

I know how family can be, but would she be opposed to taking these results to her primary care physician on her next appointment? Maybe if her doctor speaks to her she will be more likely to have further tests done. I'm sure you don't want to badger her about this, but I had an incident recently with my mother along the same lines. I normally do not say too much to family members (because I am still a kid to them), but I thought "Gosh, this is my mom, I have to speak up".

A pulse ox can be a great tool, and as ablong noted, everyone can now purchase them inexpensively on the net.

Great post topic jskinner!

[mindy]

Thanks for the info, folks! I just keep on learning as I read the posts on this forum.

Mindy