TECSA and ASV - Feel terrible even with 0 AHI

[jordache16]

For some background, I was diagnosed with OSA a few years ago and have been using a CPAP off and on since then. Historically, I have found that after 3-4 weeks of wearing the CPAP, I start to feel terrible and even worse during the day. I have used the CPAP for at least a month on 3 separate occasions during the last few years. The longest I have been able to go on my CPAP is 6 weeks which was back in April. I always end up stop using the CPAP as I get the point of being non-functional with extreme daytime tiredness that negatively impacts work and home life. One odd thing I have found is that both my bed monitor and my Apple watch show 0 REM and 0 deep sleep towards the end of this 3-4 week period. Without my CPAP I typically at least get a little deep sleep and some REM (10-20% between the two and 90-80% Core sleep). Me feeling even worse after about a month on the CPAP makes sense seeing I go from 20% deep + REM, to basically no REM and deep sleep.

With all the trouble I've been having (and terrible sleep), I asked my local sleep Dr. to refer me to Mayo Clinic to have them assess my situation and do an overnight sleep study. I was seen at Mayo 2 months ago where I found out I have central sleep apnea in addition to the OSA. Long story short, they diagnosed me with TECSA (Treatment Emergent Central Sleep Apnea) and prescribed me an ASV Bi-PAP. While I was there, I did a second overnight sleep study using an ASV PAP machine the entire night, and I had 0 obstructive events and 0 central events.

The ASV machine seemed like a promising solution and I have been using it for the last 3 weeks using the settings that my Mayo Dr. set. Early on, I had a few good nights on the ASV where I felt more rested the next day (Apple watch showed 45 min to 1 hr of deep sleep, which has never been that high). The ASV machine also shows virtually 0 AHI events every night, which is better than what my CPAP would show. The ASV definitely seems to be working better (on paper anyways) however, I've started to feel worse the past couple of days (just like with my old CPAP machine). Last night I had 0 AHI events, however I have felt like crap all day and my Apple watch shows I had no deep sleep and no REM sleep last night.

I attached the OSCAR report from last night for the ASV. For comparison, I also attached the OSCAR report from when I used my CPAP for 6 weeks in May. Here are my questions:

1) Is this normal to feel worse after a few weeks on a PAP machine before you start to feel better? Do I just need to hunker down, push through, and stick with it?
2) Why with 0 AHI events do I still feel tired and sleepy during the day? Is this just my body / brain still adjusting?
3) One thing that sticks out on the OSCAR data is the flow limits, which I believe may be something to look into. Can someone explain what flow limit is and if mine seem to be abnormal?
4) My understanding is that the ASV will learn my normal breathing pattern and will 'take a breath' for me in the event that I stop breathing due to a central apnea event. Is there a way to see when the machine does this in OSCAR?

[SarcasticDave94]

Welcome to Apnea Board,

I'm not belittling you one bit, just passing on learning experiences from my own usage. If you were issued this ASV, it is Central Apnea, not the temporary type of treatment emergent CA. The ASV is too expensive to get approval for the TECA.

Sorry for the hair splitting. OK onward. Do you have your sleep study? You can post it here, redacted of your personal info.

Answers to the questions:
1. Sometimes it does take a while to feel better when in CPAP therapy, you like most others had Apnea and sleep related issues for years, a few months of perfect therapy isn't enough, you may start to feel somewhat better in small ways though

2. Yes still adjusting to therapy, also better settings can accelerate this

3. Flow limits can't be addressed with the ASV, the FL are now a byproduct of the ASV therapy, please ignore the FL chart

4. ASV will blow hard occasionally to kick start breathing during a CA, I don't think it'll be evident if it does, unless there's a drastic increase in pressure

I would suggest considering a setting change. You're running ASV Auto mode, but EPAP 8 is both Min and Max, making that static. I would redo this. Try 6 or 7 EPAP Min and about 10 EPAP Max. Right now, every pressure increase comes from the Pressure Support, and that might be less comfortable that an actual EPAP range.

[Phaleronic]

Also welcome to the forum jordache16, along with Dave I'm not sure why your sleep professional set your epap min and epap max to the same pressure of 8cm, but I agree that it should be changed to facilitate your treatment.

[ZacharySimon]

From the NIH: 

In some TECSA cases, occurrence of CSA events during initial continuous positive airway pressure (CPAP) titration are transient and they may resolve spontaneously with chronic CPAP therapy. However, some central apneas persist even with regular CPAP therapy.


So Mayo probably believes his TECSA is persistant?

[SarcasticDave94]

We're really not here to predict or read doctors minds. I stated that normally ASV is not for treatment emergent CA, as it would be hard to get approval, and just as hard to get a doctor to script with supporting documents. If it were prescribed for TECA so be it. Regardless, the settings are lacking currently. Sleep study report and OSCAR download would help get this on track ASAP.

[jordache16]

Thanks all for the input. I will try adjusting those settings tonight. I'm not sure about the approval of the ASV for TECSA, but it may have been a bit easier as I had already been using a CPAP and have also tried an Oral Appliance.  It is also a rent to own deal where insurance makes you pay monthly for it and you have to prove you are using it at least 4 hours a night for them to pay their portion. After ~8 months I think is when I would own it outright (although I am already at my out-of-pocket max this year for insurance so I'm actually not paying anything for itl). The Dr. at Mayo also said that 80% of his patients see the TECSA get better within 6 months of using an ASV and in many cases, individuals are able to move on to alternatives to treating just the OSA side of things since the CA side is resolved.

Here is the split night sleep study from Mayo. The first half of the night was my baseline with no CPAP, Oral Appliance, or anything. The second half of the night was with a CPAP. From the sleep study you can see how the first half of the night I had quite a few obstructive events (but no central events). The Dr. said my AHI would have been even higher if I actually had gotten into REM stage. Then the second half of the night with the CPAP, I had no Obstructive events, but all the sudden central events start popping up.