[Diagnosis] Sleep Study - what do some of these things mean?

[SnoringTyger]

Hello all and thanks for reading!

I'm new to the CPAP community, and just received my device after ordering it online (local providers have a 300+ person waiting list...) so I haven't been given a lot of guidance, and am relying on what I can find online.

I was pretty happy with the what I've learned but just went to look at my sleep study report again and... realized there was a whole second page with more data that I had not even noticed!! Silly me. But now I have more questions about that. I know nobody here can give medical advice- I certainly don't expect it!- just hoping someone can help me interpret this data. I do plan to go back to the Dr after using the machine for a while but don't want to wait that long to learn.

I've attached the more interesting page of my sleep study results. This was an unattended home study. Here are my variety of questions...
1. At the top section, I see the description of OSA events, CSA, Hypopneas, etc... but then it just says 'Non CMS Events' and has a much higher number than the others. What are 'Non-CMS events' ? 
2. I see 'Total # of Desats = 45' - I understand this to be oxygen desaturation events. Is 45 a high number? What would be common numbers for this? Should I be more concerned about these desat events than OSA? My number of obstructive events is pretty low. Why would my oxygen go down 45 times when I only had 9 obstructive events? 
3. I see my lowest oxygen desat was 89%. In comparison to normal people, and others affected by sleep apnea, where does this land? Is this concerningly low, or relatively a none issue?
4. Is 95% oxygen average good? Should it not be more like 99/100?
5. It says my man heartrate, during sleep, was 109. That seems pretty high for sleeping heart rate? What are some reasons this would be so elevated?


Sorry for all the questions! I think I've figured out a lot of the rest using google-fu. Obviously this is listed as a very mild case at 6.1 AHI, but I'm only in my twenties so if I'm going to be strapped to this device for the rest of my life I'd like to understand it a bit more. 
I do have anxiety, excessive daytime sleepiness, and (the big reason for the study) my husband says I snore and 'choke' often in the night and it keeps him up and is obviously a bit concerning. So I'm certainly willing to give this thing a try.

I have ordered the Resmed 10 Autoset, and last night was my first night with it. I used the P10 mask but also have the N20, and just ordered the N30i + P30i cushion, and F30i just to get a good range of masks to test with since the site I ordered from has a 30 day return window for masks. Trying to keep my mouth closed while I slept was a bit annoying last night as it tends to fall open when I doze off. I also had the mask a bit too tight and had to loosen it in the night because it was hurting my nose. I plan to use OSCAR but my device didn't come with an SD Card, so I have that ordered and will probably return with my OSCAR data once I have it :


Thanks again for the help! You have all been a wealth of knowledge already!
-Tyger

[quiescence at last]

i don't know what non-CMS events are. You can be desaturating due to some other cause than breath cessation (apnea) or hypopnea (somewhat reduced flow intensity). It may be some other lack of gas exchange in your lungs due to not enough volume of air, too lean of oxygen in the air (like at higher altitudes) and then there is a lung gas exchange insufficiency issue called COPD. Once you do CPAP for a little while we may see the oxygen levels level out some. It this did worsen (much much worse so don't worry) the doc would prescribe supplemental oxygen. 95% is somewhat below what most healthy adults have while awake. If CMS stands for "Centers for Medicare & Medicaid Services", then non-CMS events are possibly those things that CMS does not consider sleep disordered breathing. I know at one time some agencies and insurance policies did not consider "Respiratory Effort Related Arousals (RERA)" as a sleep event to be counted. I have many RERA events but a lower AHI, so that matters to me. Lucky my doctor feels RERA are important enough to deal with.

You have some great scores if you sleep on you left side, and reasonable scores if sleeping on you right side. So that is my suggestion to leave with you.

Good luck, and we will be looking for data from OSCAR, etc.

In the meantime, you should be able to read some information from the device screen itself, like 90% pressure reached, and AHI for the night, and maybe also for last 3 days or a week.

QAL

[GuyScharf]

That's an interesting report because it shows both apnea events as scored by CMS and AASM standards.

CMS is the Centers for Medicare and Medicaid Services. It's standard requires a 4% oxygen desaturation to count as an event. AASM is the American Academy of Sleep Medicine, and they require only a 3% desaturation for the event to be counted. So the AASM standard is more sensitive.

Looking at your report, it appears that non-CMS events are those that meet AASM standards but not CMS standards. Thus AASM events = CMS Events + non-CMS Events.

[DaveL]

Welcome to the forum!
I appreciate your post. I learned a lot from the answers.
I hope you enjoy OSCAR. My treatment has improved so much after acting on recommendations from experts here.

[Geer1]

It gets kind of confusing with how they list everything but with a little interpretation it is clear that the number of apnea and hypopnea specified are using CMS definitions (9 + 13 = 22) and then non CMS events are 37 more hypopnea that meet AASM but not CMS criteria.

In short you had 59 AASM events and 45 of these resulted in a desaturation. Your AHI of 6.2 only just meets the definition of mild apnea. You have snoring as well which further supports some mild obstructive apnea.

Your 95% SPO2 average is good and no time spent below 89% is also good. Your max heart rate was a tad high and probably following one of the longer apnea or perhaps not even breathing related. Your mean heart rate was good so it was likely only a momentary high.

Overall this looks like basic mild obstructive apnea and the autoset should treat it easily.

[SnoringTyger]

Hello again!

Thanks everybody for all your advice/help so far Reading the forum has been very helpful! Tons of great information!

I've done plenty of mask experimentation and had some fun with the settings just to learn what they all do. Considering upping the minimum pressure but wanted to post last night's OSCAR results and get some experienced opinions

Would like to get/keep AHI under 1 if possible. I've had some nights under 1 but mostly am around what you see in this screenshot. Compliance hasn't been difficult for me (I'm very grateful) and I would say I'm pretty used to the machine. 

Any thoughts on if these settings need adjusted?

Thank you so much!

[Gideon]

First your target of "AHI under 1" is not a good target. The target is to consistently get good restful, and relatively uninterrupted sleep. DON'T chase numbers. So How do you feel? Please answer critically.

Your min pressure of 4 is preventing EPR from treating your flow limits and hypopneas and is causing your pressure to swing far more than it should be.
Set Min Pressure = 7. That may be increased depending on the results.

[Geer1]

Just a bit more on Gideon's post. EPAP = Pressure (IPAP) - EPR. When you look at your pressure chart in OSCAR you can see two lines, a red line and a green line. The red line is IPAP and the green line is EPAP. These lines should move in unison to each other but because the lowest pressure the machine can go is 4 cm when operating at IPAP of 4 cm the effective EPR is 0. In order to get full time EPR of 2 the minimum pressure has to be at least 6 cm.

7 cm min pressure would be a good change to ensure you always have full EPR (and imo this should be the default minimum all machines use). 7-9 pressure range is quite small though so I would also increase max pressure to 12. The machine will only increase pressure if needed and it is best to leave the machine some space to run. The only time we usually limit max pressure is if we are sure higher pressures are not helping and they are creating negative effects (aerophagia etc).

[SnoringTyger]

Hmm interesting! 7 sounds sorta high when the doc recommended a max of 8?

I had EPR off at first and only added it at a 2 after my husband complained one night I was exhaling really hard in my sleep (he described it as a 'huffing' sound) - would EPR be better set to off? Or lower?

My AHI was just mild (6.1) so my apnea isn't horrible but I do have daytime sleepiness. Honestly it has been better, but I think it's even better on the nights I had under 1, so that's kinda why it was my goal. And my husband is thrilled that my snoring doesn't keep him up with this thing haha. I've actually been dreaming too which has been neat.

I'll try raising the pressure tonight and see how it changes things!

[Geer1]

7 cm is not a high pressure and a max setting of 8 cm by your doctor is quite low. I assume he figured that with your mild AHI and them predominantly being hypopnea that you wouldn't need a high pressure.

So far he looks mostly correct but I think the higher end of his settings will give you the best therapy for two reasons. 1) Higher pressure will give you full benefit from EPR. 2) Higher pressure will help avoid the odd remaining apnea and could lower your AHI further.