Recent poor results - ASV

General Discussion on any topic relating to CPAP and/or Sleep Apnea.
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Respirator99
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Recent poor results - ASV

Post by Respirator99 » Mon Apr 06, 2026 8:17 pm

Hi all

I use a Resmed Aircurve 10 ASV. For years my AHI has always been less than 2.0 and my hours have been good enough. Over the past few months, AHI has gone high and I'm turning the machine off in my sleep. I have tried increasing pressures including max & min EPAP as well as increased PS max & min. I have a number of conditions but heart and lungs are sound. I take enough meds to stock a pharmacy plus medicinal cannabis.

Any suggestions gratefully received - last nights trace is attached.


https://sleephq.com/public/teams/share_ ... 39bc76acc6
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Nocibur
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Re: Recent poor results - ASV

Post by Nocibur » Tue Apr 07, 2026 5:28 am

Look at "Mask Pressure" in Oscar during those concentrations of UAs.

Any tubing occlusion, clogged filter, displaced humidifier gasket(s), foreign objects, blower failure, fried PCB, etc. should have generated an Error Code.

Try another machine.

Find somebody with ResMed Service Connect and run the diagnostics on the machine.

Get another NPSG. Make sure there's effort belts if a home test.

Night video recording to see what's happening during the UA salvos. Head & neck position.

Try all those neck pillow tricks.

ENT guy to see if something's flopping around in there.

Sleepzilla
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Re: Recent poor results - ASV

Post by Sleepzilla » Tue Apr 07, 2026 6:51 pm

Your respiratory rate, tidal volume, and resulting minute volume values are all over the map, and way outside of normal ranges.

Not sure if this is inherently physiological in nature, or due to your unusually high therapy pressure settings and the machines inability to resolve your UA events using them.

The ASV doesn't have the technical ability to definitively discern between OSA and CSA events. Instead it assumes—and normally quite accurately so—that its continuously varying PS capabilities effectively resolve all central events, and that any remaining events detected then must be central in nature. So the ASV reports those assumed obstructive events as Unidentified Apnea (UA) because it can't prove for certain that they indeed obstructive. (This is also mentioned in the Sleep Reports section of the ASV 10 machine's Clinical Guide.)

Anyway, most all of your UA events are occurring at the machine's max capable pressure of 25 cm H2O, which appears to indicate major obstructive events. Without further information, my money is on some form of positional OSA.

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Respirator99
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Re: Recent poor results - ASV

Post by Respirator99 » Wed Apr 08, 2026 7:43 pm

Thanks for the suggestions. I'll work through them and see what happens.
* Download Oscar
* Oscar help
* An alternative to Oscar - try SleepHQ

I have no medical training or qualifications. Take my advice for what it's worth.

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Nocibur
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Re: Recent poor results - ASV

Post by Nocibur » Thu Apr 09, 2026 4:41 am

OK but can you do an image of
Nocibur wrote:
Tue Apr 07, 2026 5:28 am
Look at "Mask Pressure" in Oscar during those concentrations of UAs.
and also lots more SleepHQ with lower pressures and an overall trend.

While there is some stuff that might look obstructive
paul.jpg
paul.jpg (21.58 KiB) Viewed 119 times
it may (probably) be faux (engineered by the machine mode) and could be confirmed by looking at the Oscar pressure waveform.

Due diligence to R/O obstruction, but IYAM IMO those crazy pressures are generating hyperventilation and subsequent hypoventilation to get things back to normal.

AAMOF it looks like a lot that stuff isn't even sleep.

BTW what was your screen name "over there"? I forgot.

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Nocibur
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Re: Recent poor results - ASV

Post by Nocibur » Thu Apr 09, 2026 6:31 am

Nocibur wrote:
Thu Apr 09, 2026 4:41 am
...IMO those crazy pressures are generating hyperventilation ...
...and hyperinflation.