Aircurve 10 VAUTO Not pushing Air!

[DFWdude]

I notice that your pressure starts lowish and very soon shoots up much higher.  Are you using ramp?  If so, turn it off.  Your therapy will be better if you do so.  

Actually, I like the ramp.  It makes it easier for me to fall asleep before the pressure gets too high.  As long as my AHIs are less than 5 or so, I assume I'm receiving good therapy (normal for a person without SA).

[Sleeprider]

I suggested earlier that we could try a lower minimum EPAP pressure of 10.0 rather than 14.0. Using the lower pressure would let us see what the auto algorithm requires to prevent obstructive events. With your current minimum of 14.0, the pressure never changes, so it is likely higher than needed. It's your choice, but it would be interesting to see if more comfortable therapy is available with a lower minimum pressure.

[DFWdude]

I suggested earlier that we could try a lower minimum EPAP pressure of 10.0 rather than 14.0.  Using the lower pressure would let us see what the auto algorithm requires to prevent obstructive events.  With your current minimum of 14.0, the pressure never changes, so it is likely higher than needed.  It's your choice, but it would be interesting to see if more comfortable therapy is available with a lower minimum pressure.

I will consider this after I confirm to my satisfaction that the current new settings continue to provide the results desired.

If I eventually drop the minimum to 10, then I likely could turn off ramp as well.

[Weld3z]

[quote='Weld3z' pid='524937' dateline='1722395884']

We have a close number my pressure is 14/20 but with 4 pressure support, we have the exact problem the only difference is I'm new to the AirCurve ( you are not ) my old device was pushing air stronger than the new device.
Because no help here!! I talked to my doctor yesterday she told me there is a very small percentage of patients who may feel the change between devices but for me is not a small issue I can't sleep more than 3-4 hours, sometimes I feel that I need to go back to my old device.
She advised me not to think about how strong or weak the air is if events are under control also she asked me to increase the ramp to 7 for now and to take 10mg of Zolpidem for couple of days until I used to it and sleep enough, told me to wait for a month if it still bothering me she will find a solution.

By theway latest sleep study done with S9 was also weak air feeling,My latest AHI 83

Some advice to turn of the ramp wich is big No for me I can't do it tried but failed talking is easy but under big pressure no way someone can sleep!!

[Sleeptechmaster]

I see what's happening. You know your obstructive apneas are well controlled at epap 14 with possibly using more pressure than needed. It looks like your machine likes the ipap of 20 max to control hypopneas.

From all the nights you posted your having a short inhale (2 seconds) and a very long exhale (8 seconds). Your body is fighting and using too much energy to exhale against the pressure.

What you are experiencing when you are noticing that the machine isn't 'initiating a breath' is that your body is experiencing the very long labored exhale which is causing an arousal.

You are experiencing hypercapnia which is a build up of CO2 in your blood from not being able to exhale it all as you would normally.
When you are waking up you have a large build up of CO2 as well as limited oxygen issues. Your body knows that increasing its oxygen actually makes the hypercapnia worse. So you are experiencing a post arousal central where your body is resisting the urge to inhale due to being overloaded on CO2.

So basically your body is fighting the machine the entire night as it is forcing a lot of air and oxygen into your lungs to control the hypopneas.
Due to experiencing this issue it is good you are on bilevel, but your pressure support is far too low. Anything under 4 and bilevel is not able to function as it should. The main benefit of bilevel is the ability to increase the pressure support higher which is exactly what you need.
I would definitely use
IPAP Max: 20
EPAP min: 8
Pressure support: 8
That way the machine has your hypopneas covered and can increase between 8 to 12 EPAP for your apneas as needed. You'll also feel more energy during the day since you won't be spending so much energy breathing during sleep.

Ti Max: 1.5, TiMin 0.3.
This is made to help limit your inhale time to not be overloading yourself.

[Sleeprider]

Um, no to PS 8.0. I don't know what sleep tech this new member is a master of, but it should not be yours.

[DFWdude]

I suggested earlier that we could try a lower minimum EPAP pressure of 10.0 rather than 14.0.  Using the lower pressure would let us see what the auto algorithm requires to prevent obstructive events.  With your current minimum of 14.0, the pressure never changes, so it is likely higher than needed.  It's your choice, but it would be interesting to see if more comfortable therapy is available with a lower minimum pressure.

So, last night I dropped the EPAP to 12, and cut the ramp time to 10 minutes.  I felt only moderate relief throughout the night.  When I woke up at 4:30 for a health break, I could not establish a clear airway (nose), hence the centrals the rest of the night.

Back to EPAP 14...

[Sleeptechmaster]

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Um, no to PS 8.0.  I don't know what sleep tech this new member is a master of, but it should not be yours.

Explain your reasoning then instead of "um no".

[SarcasticDave94]

Not answering for Sleeprider, but typically a PS of 8 will increase Central Apnea, if there's no backup breath rate function. When I was on ASV, I could use PS range 3-15, because ASV uses backup rate.

By the way, Sleeptechmaster, you don't have any CPAP info filled in on you left panel user info. No CPAP but overflowing with input that's not ideal?

DFWdude,

Just one possibility there in this OSCAR chart, last segment, maybe it's SWJ (Sleep Wake Junk) issue. The pattern can crop up because the CPAP user is transitioning frequently between sleep and wake breath control, mass confusion results and lots of events appear. These will show up on the bookends, beginning or ending of therapy sessions/segments, much like this.

[Sleeprider]

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Explain your reasoning then instead of "um no".

PS at 8.0 will result in excessive CO2 washout and make central apnea problems much worse. This individual shows a normal I:E ratio and no flow limitation, so attempting to manipulate respiration timing or volume with unusually high PS would certainly be counter-productive.  Very high PS with a spontaneous triggered device has been tolerated by a very limited number of individuals attempting to treat very severe flow limitation, but generally these are the exception rather than the rule. On the other hand, any suggestion I have made has been summarily dismissed as well, so I'm probably done here.