FL diagnosis / Treatment help

[gregbe2000]

(I'm posting a new question after I added this to my original, and really dated, thread around CSR/CAs. It's an older problem and this issue was a red herring for me...6 months later I realized this).

Background:
* I've been on CPAP for 5 years for a diagnosis of moderate OSA. I've used it consistently but I never feel refreshed in the morning. My AHI is fairly low and almost zero for obstructive events. My AHI usually ranged from 5-10 and was dominated by CAs. A took a deeper dive about 8 months ago after discovering OSCAR and have evaluated these CAs, which are almost always in the 2nd half of the night, to be arousal-based CAs or sleep/wake transition CAs. I've ruled out treatment-emergent sleep apnea.
* My subjective sleep quality is almost always very poor. My sleep is extremely fragmented (as per my garmin watch and past sleep studies).
* I've come to the conclusion that my CPAP treatment does effectively treat my obstructive sleep apnea (which was almost all hypopneas in my sleep study) but that my sleep quality hasn't improved because of the sleep fragmentation, and that fragmentation is due to a high number of arousals due to flow limitations. CPAP with EPR of 3 helped round out the top but didn't help enough - and didn't improve my subjective sleep quality
* I've had a few sleep studies in the past 5 years but UARS wasn't identified. A sleep study a few years ago yielded an AHI of 8.7 and RDI of 21.
* I had 3D CBCT imaging done a few years ago and it revealed a very narrow airway bottleneck of 68mm2.
* I'm a couple days into a bipap (aircurve 11 Vauto) and hoping I can find settings that improve my sleep quality.
* I thought I'd start conservatively with EPAP of 8, PS of 3, and IPAP of 11. I then moved to EPAP of 9, PS of 3, and IPAP of 12. Still feel really bad in the morning and my flow graph still looks bad.

Questions:
1) The rounded tops of my respiration don't look horrible to me. I think my issue is that the inhalation of my respiration for 50%+ of the night pauses (goes horizontal) halfway up for 0.3 to 1 second and then resumes going up. I think this pause, which goes undetected with Resmed's FL metric, is the result of persistent flow limitation that is leading to arousals - some of which are minor and some of which lead to CAs - but all of which fragment my sleep. I'm looking for feedback on whether or not this is a real issue - for whatever reason, I can't find FL examples that look like mine.
2) If the answer is yes that's an issue, then what should I do settings-wise? I'm going to try EPAP of 9, PS of 4, and IPAP of 13 tonight, and change trigger from Med to High. I'm hoping more of pressure boost, and early on in the inhalation, will help with this.

I've attached a 2 min zoom-in on my respiration in 1st half and 2nd half of night. Any help would be really appreciated.  Thanks!
   
   

[Deborah K.]

We can better help you if you post the whole night chart instead of the small sample.

To help lower your CAs, you need to set your Trigger setting to high or very high.  This will lower them considerably.

Try the trigger change first, then see how it goes.  If they are still pretty high, raise your Cycle setting to high, then see if that helped.

[gregbe2000]

Thanks Deborah H. I'll attach the whole night when I can - right now it's giving me an error.

I will change the trigger to high for tonight.

Do you think the pause in my flow half-way up in most of inhalations is a true concern and possibly behind my sleep fragmentation? Just trying to understand if this is something I should be trying to eliminate with the proper settings or if it's a red herring. I've had many nights with a low AHI (low CAs) but I still feel very bad in the morning. I always have these FLs in my flow chart though -even though my machine often reports < 0.02 in FL for 95% of the time. My hypothesis is that these FL that I think I see visually (if that's what this represents) are the source of my arousals and CAs. Does that hold any water?

[gregbe2000]

Hoping someone can help - posting again.  I tried EPAP of 10, PS of 4, and IPAP of 14.  I again feel very bad in the morning and this time it's lasted throughout the day.  I would love help to understand my zoomed-in picture of the flow rate.  The PS does help to round the tops, but I have these 0.5s to 1s stalls that I think are coming right before my inhalation.  I'm not sure if this is normal, if it's the root of my sleep fragmentation, or how to change my settings to address it.  Any help greatly appreciated.