AutoSV data interpretation assistance needed

[PappaJoe]

Trying out a PR BiPaP AutoSV Advanced Sys One.
PR does not provide Flow Limit data, Just flags events.
It flagged 7 FL last night. Visual inspection of Flow Rate shows continuous flow limit.
Is this waveform normal for an ASV machine?
Thanks in advance for any suggestions.

       
This my first attempt at posting screenshot from OSCAR.
Pls let me know if they are visible.

(Additional problem:  Machine was in different time zone so is offset from O2 data.)

[Sleeprider]

How did you acquire this machine? It is a recalled device by Philips. It looks like you are using AutoSV mode with EPAP min 5.0, EPAP max 15.0, PS min 4.0, PS max unknown. You don't appear to be using this to treat central or complex apnea and the event rate is very low. I don 't see many departures from PS 4.0, but EPAP ranges mostly above 6.0 to 10.0. It appears you are using this mainly as a BiPAP device rather than ASV and your settings might be optimized a bit differently in that case. The flattened inspiratory peaks are less to do with flow limitation than the square-wave delivery of pressure. You might be able to increase rise time to improve that.

Let me know what your objectives are for using this device and why you switched from the Airsense 11.

[PappaJoe]

It was a deal 'that could not be refused'. Under $200
6 new masks with headgear, etc thrown in.
(A thorough cleaning included removing foam.)

Concern 1:  Flow rate with Airsense 11 never flattened no matter the tweaking.
Concern 1.5: Leaking and flow limit excessive.
Concern 2:  My recently purchased O2 Ring shows deep dips, sometimes into the 70s.
Neither my doctor or equipment provider are interested in my concerns, because, "Your numbers look great".

Maybe I'll end up back with '11 CPAP
But machine gives me the opportunity to explore different PAP methods.

So trying AutoSV first.
I'll try BiPaP soon.
If this were you experimenting on yourself, how would you optimize BiPAP settings rather than using ASV?

But as you know, there are many relatively small tweaks that show all the world of difference.
Trying to do this blind is a herculean task.
Nevertheless, the reward is worth the effort.
Thank goodness this forum, et al.

PSmax = 20

Thank you

[Crimson Nape]

PappaJoe - Oats that have gone through the horse are always cheaper.

- Red

[Sleeprider]

PappaJoe, my interpretation was correct then. You're doing just fine with these settings. I would increase EPAP min to match your median or maybe the 90th percentile pressure and narrow the range of PS. I think PS 4 looks pretty good here, but I don't see a need for more than PS 6.0 as a max. I would increase rise-time to 0.6 and see if that smooths things out.

[PappaJoe]

it's risetime settings are 0 1 2 3 so i changed from 1 to 3.
Cannot wait for bedtime.
Thank you, Sir

---

Thank you, Red, for those true words of wisdom.
It is also true that a wise man lives within his means.
I'm just a wise guy struggling to become a wise man.

[Sleeprider]

It will be good to see your results. Talk to you tomorrow.

[PappaJoe]

This is not the outcome expected.
3 sessions. changing masks each time...
1. F&P Simplus full face mask & cervical collar
2. Dreamwear with under the nose cushion & cervical collar
3. Airfit P10 (large pillows)
Not too sure I fell back asleep on 3rd round
           

[Sleeprider]

I think we see a better shape to the inspiration wave due to the increased BiFlex or rise-time setting. Lots more hypopnea, may indicate you should increase the range of PS. In fact in spite of the reduction of PS range, you actually had higher IPAP pressure. Maybe let's keep the change in rise time and go back to EPAP min of 6.0, PS 4.0-10.0

[PappaJoe]

Okay, Sleeprider,
Changes are made.
This is the first time since beginning PAP therapy that the AHI exceeded 5.
Gonna improve for sure.
I did add the shot showing the O2 dropping to 81%.  
In your experience do others share that problem?
Thanks for your guidance.