New Poster, not so new CPAP user, requesting help

[Cyberrabbi]

Howdy all. I apologize if I am doing this incorrectly or on the wrong board. Basically used an Amazon mouth guard for my snoring (and likely apnea) for a few years with great success but it slowly messed up my jaw/teeth. Got on CPAP to try to give my jaw a chance to relax back into its natural position and it was miserable. Nasal pillows didn't work because I'd open my mouth and air would escape, seemed to have tons of micro-arousals, and full face mask (which I tried several) were too uncomfortable or would cause just as much microarousals if I shifted even slightly. Mouth tape rarely if ever worked, and I couldn't use a chinstrap because the purpose was to let my jaw relax into its natural, healthier position. So I gave up and actually slept okay/better without it as I was diagnosed with mild sleep apnea anyways because the sleep study had 12 AHI or something.

I recently got Invisalign to try to get my teeth/jaw fixed so I can eventually get a dentist made mouthguard as that worked super well.  And now I snore horribly again. It's unclear if I'm just waking myself up from the noise as I'm not used to my own noise or actual apneas. So I've started trying the CPAP again, and thankfully the combination of chin strap and careful mouth taping makes my leak rates (at least at the pressures I use) negligible.

My AHI has always been consistently fairly low with any CPAP at all (almost always sub 5 but usually even sub 2), but I can tell I am waking up quite a bit more at night than I was without CPAP or Invisalign. When I use a lower pressure (like seven) I have less apnea events but I feel loopier the next day, if I have a higher pressure (like 9), I have more apnea events (usually central), I feel similarly tired but more "normal", it makes me think that despite lack of apnea I'm not getting enough oxygen with lower pressures?

I also used two different oximeters while awake and my normal CPAP levels, from 7-9, appear to decrease my oxygen saturation by maybe 1-2 percent even while awake (that or about the same as regular breathing), whereas if I put it up to around 12, my oyxgen levels go UP by 1-2% from non CPAP levels.

My question is what are y'alls advice given the data? Go as low as possible without having increases in apnea and hope I get used to it? Go for medium (like 8.4) and try to get the best of both worlds and hope I just adjust? Aim for higher so I get more airflow/less microarousals (possibly)/higher oxygen and hope CA events go down as my body gets used to it?

I also think I'm a light sleeper so have avoided the APAP function if I can help it.

Thank you very much in advance for your help/time. I just want to at least last until I finish out my Invisalign but this is pretty miserable.

[jdougc]

Welcome to the forum. Can you post a couple of your sleep report with your info redacted?
Your flow limits are constant through the night and just a bit high.
They may be causing you arousals.
Browse through while zooming  your flow rate chart and see if the gasp line up with the flow limits, which are restrictions in your airway. Might not line up perfectly,
Try EPR of 2 and the higher pressure of 9 for a few nights and see how you feel.
You may have less arousals.
You may see more CAs and you get used to this change, they may be treatment emergent.
You get the importance of how you feel and how clear your head is, that is great.

[Deborah K.]

You might get better therapy if you use a narrow range of pressure in the Apap setting. I suggest you try 6 to 9 and see how you feel. No one breathes at exactly the same pressure all day or all night. It varies as we move, sigh, etc. With a narrow range, I can't imagine you will notice the difference, but you will get better treatment. Give it a try

[jdougc]

Since you are a light sleep avoiding APAP is probably a good move as those flow limits would cause the pressure to go higher and then fall back most of the night.

[Cyberrabbi]

Forgot to reply with quote, for jdougc:

I only had the one study to get the CPAP machine and I don't think it's representative of current sleeping as it had no machine, and I intentionally did not elevate my head to have the highest chance of displaying apneas.

I'm not sure how to identify gasps but I'm assuming it's when the flow rate has spikes in either direction (which from my understanding is usually a sign of a microarousal), it's odd that there's definitely some overlap sometimes, but sometimes I have spikes in flow rate while flow limit is 0, and sometimes flow limit spikes but there's no change in flow rate.

I remember reading somewhere on these forums that for each increase in EPR it makes the functional inhale pressure go down so you need to adjust it? Like a 7 with 0 EPR is similar to a 9 with 2 EPR? Is that true?

Regardless thank you for the suggestion and I appreciate the help : )

[Cyberrabbi]

You might get better therapy if you use a narrow range of pressure in the Apap setting.  I suggest you try 6 to 9 and see how you feel.  No one breathes at exactly the same pressure all day or all night.  It varies as we move, sigh, etc.  With a narrow range, I can't imagine you will notice the difference, but you will get better treatment.  Give it a try

Hey Deborah! Thank you for the response. Genuine question, is there a benefit to having a range like that when AHI is low? My understanding is the APAP wouldn't adjust the pressure really unless it sensed increased apnea events (or I guess maybe increased flow limit over time). Plus given that the issue appears to be micro-arousals rather than apnea events, I'm worried that having the pressure change on its own might increase micro-arousals given that I believe I'm a light sleeper.

If I'm completely off base, please forgive my ignorance.

[jdougc]

A 7 with 0 EPR is similar to a 9 with 2 EPR, but Resmed's EPR has a delay in recovery the pressure after an exhale, which is kind of bad.
You do have the gist of it.
I never reply with quote, just paraphase to see if I understood the original post, .

[Cyberrabbi]

A 7 with 0 EPR is similar to a 9 with 2 EPR, but Resmed's EPR has a delay in recovery the pressure after an exhale, which is kind of bad.
You do have the gist of it.
I never reply with quote, just paraphase to see if I  understood the original post, .

Oh no sorry, I meant that -I- didn't reply with a quote accidentally when I originally posted, so I edited it to make sure you knew I was responding to you. Dumb question: Will flow limit spikes show up when there's difficulty exhaling as well?

[jdougc]

Not a "Dumb question: Will flow limit spikes show up when there's difficulty exhaling as well?"
Yes, you can see them. Sometimes squiggly artifacts and other things
I will let a more experience person respond on how Resmed mesures/counts that.

Expiratory Flow Limitation (EFL) is similarly restricted flow rate during the exhale cycle
https://www.apneaboard.com/wiki/index.ph...limitation

[Cyberrabbi]

Not a "Dumb question: Will flow limit spikes show up when there's difficulty exhaling as well?"
Yes, you can see them. Sometimes squiggly artifacts and other things
I will let a more experience person respond on how Resmed mesures/counts that.

Expiratory Flow Limitation (EFL) is similarly restricted flow rate during the exhale cycle

I appreciate you sharing that. From cursory searches of the forums I've seen it said that having flow limit at less than .1 at the 95% range is pretty good, to which mine seems to be pretty consistently .03 or below.

Is it reasonable to think that I might be having microarousals from not -exhaling- properly even if it doesn't show up on flow limits? Because looking at the spikes in flow rate I think you have a decent idea, because it looks like fairly often I'll have an inhale that doesn't have a full exhale, then I might hold my breath for a bit, finally exhale the rest, and then take a bigger inhale. But during a lot of these there's no registered flow limit issues.