Finally, SUCCESS after almost giving up on CPAP (retitled)

[Computerdoc]

Last nights Oscar charts.  Feel pretty rested this morning (I'm generally a slow starter in the morning even with the best night's sleep.  I did experience some daytime sleepiness, a couple of micronaps while reading.  That often happens in the first half hour after dinner while watching the news.  Watching Ken Burns documentaries is a reliable activity for dropping off to sleep unintended.  My biggest OSA related complaints are general daytime tiredness, and an inability to read a book or watch a TV documentary (or a boring movie, for that matter) and not be able to stay awake.  Don't know if that information is helpful, but there it is.

I did buy a soft cervical collar but haven't tried sleeping with that on yet.  I'd prefer to sleep without it if I can.  Just more "stuff."

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[staceyburke]

One night does not change everything but according to this one, no collar is needed.  Great night, maybe 3 or 4 like this and you will be feeling better.

[Sleeprider]

I agree a collar is probably not needed.  We continue to see a lot of variable breathing, and I though you might like to see the definition of that term we have in our Wiki Glossary.   In your case, we know the root cause of VB is flow limitation and recovery breathing which is very disruptive to sleep.  The best solution for that is indeed bilevel pressure support to mechanically assist in reducing flow limitation from airway resistance, and evening out respiration.  The definition below suggests that the VB controller over-rides the pressure the primary pressure adjustment system that causes the CPAP to increase pressure ahead of events.  This likely accounts for the very flat, unresponsive pressure line we see in your graphs.  In other words, the fact you have persistent flow limitations and recovery breathing means your auto CPAP is under VB algorithm control and is not responding as a normal auto CPAP.

Variable Breathing - Philips Respironics variable breathing algorithm seeks to develop a peak inspiratory flow trend on a 4 minute moving average, and measure the deviation above or below that trend. The system is designed to identify variable breathing and to turn over control of the pressure support system, from the auto CPAP controller to the Variable Breathing controller. Without figures, we don't know what that controller response is, but it seems if VB is detected while the pressure is steady, the VB controller will maintain that pressure, but if pressure was increasing before VB controller took control, the pressure is reduced up to 2-cm. Similarly if pressure was decreasing ahead of VB detection, the VB controller will in increase pressure up to 2-cm. The duration of VB controller action is 5 minutes unless VB is still detected.

[Computerdoc]

The way I read your analysis suggests that a Resmed Aircurve 10 VAUTO would be a better choice for me than the Resmed Airsense 10.

Why does the Respironics have a VB algorithm that seems to work opposite to how it would work under autocpap algorithm control, and opposite to what is needed when variable breathing is detected? Is there any way for the user to turn off the VB algorithm control in the Respironics?

I'm relieved to hear that a collar is probably not needed. Does that imply that my OSA is not positional? My sleep study in June 2017 showed a Supine AHI of 38.6 and RDI of 85.7, and a Non-Supine AHI of 7.7 and RDI of 18.4. This led my sleep doctor to conclude my OSA was positional. From the titration report in December 2019: "CPAP pressure of 6 cm/H2O was adequate for control of sleep-disordered breathing in all positions. There was not much improvement with higher settings." But at 6 cm my AHI was still 1.9.

[Sleeprider]

As far as positional apnea, we are mostly concerned with airway restriction that usually shows a signature "clustering" of events. You have very few events, but very persistent flow limitation.

The rationale behind the Respironics variable breathing algorithm is to mitigate breathing oscillations related to central apnea and being near the "apneic threshold". The problem is that the VB algorithm has no way to distinguish obstructive variable or periodic breathing from obstructive flow limitation and arousal. Remember when I first mentioned the variable breathing, I said it can originate from either central or obstructive issues and asked for the close up zooms. Oscar gave us the answer that the Philips algorithm cannot distinguish that your VB is obstructive. If I was a consultant to Philips (I'm not), I would refine this VB subroutine and identify flow limitations, then cause the pressure to increase. The way it currently works, it paralyzes the auto pressure routine and flat-lines the machine response when you clearly need more pressure to overcome the flow limits.

Your chart was so instructive of how the VB algorithm can over-ride the auto-pressure algorithm, I added it to the wiki. http://www.apneaboard.com/wiki/index.php..._Breathing I'll eventually copy you image and put it in there, so please don't delete it for now.

[Computerdoc]

Feeling more tired this morning.  Ordered Resmed Aircurve S10 Vauto yesterday from #2.

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[staceyburke]

Good for you, great company and I think the best machine out there for “simple” apnea.

[Crimson Nape]

Congratulations on getting an AirCurve 10 Vauto. However, your leaks are very excessive and I doubt any machine will offer the proper therapy until you get them under control.

[OpalRose]

Ditto above... leak rate is too high.  

I think you will receive better results and be more comfortable with the AirCurve once your leaks are controlled.  

http://www.apneaboard.com/wiki/index.php...tion#Leaks

[Computerdoc]

I see what you're saying about the leaks.  Looking back over this last week it was by far the worst night for leaks.  I'll certainly look into that and try to correct it tonight.

Thanks!