Flow Limitations?

[gr3gg0]

Hi All,

Can anyhow help me understand what my flow chart close-up is indicating?  While my breaths are not perfectly rounded, there is definitely a plateau shape that forms once I'm asleep (when awake they are very rounded).  From the OSCAR guide it looks like a Class 4 which says Yes/No under Flow Limitation which is somewhat confusing.  Is it or isn't it?  And if it is what might be the explanation?  

Much of my breathing during the night looks like this with some increased flattening at times but usually part of the downward flow, and while sometimes dips then flat, never peaks again then continues down.  When an actual obstruction is approaching it becomes much flatter at the top and generally looks more "chaotic".

I've also included my OSCAR settings which show very little flow limitations or leaks overall.

Any help explaining what this means, and any ideas on how I can reduce them (if in fact they are FL's) is much appreciated.

Thank you!

[PeaceLoveAndPizza]

To my eyes those are flow limited breaths, just not enough to trigger the FL counter. 

You could try increasing EPR to see if it rounds out the peaks or increase pressure from 10-14 to 11-15 to see what it does. The fine-tuning requires experimentation at this point in your therapy.

[gr3gg0]

I would agree, thanks for the input.

What I've noticed is raising the EPR (I had it at 3) didn't seem to help and only served to further reduce the flow limitations on the chart hence the algorithm for the AirSense would never increase pressure even though these limitations were visible on the flow chart.

I dropped it back to 2 hoping it would be more reactive, as you said there are limitations but my AirSense isn't acknowledging them as such.  I had read that adding EPR can make the AirSense less sensitive to FL's so while the FL chart looks great the flow chart still shows the plateaus and there is never any pressure increase when they happen.  Also noticing the AirSense in APAP mode seems to react late or reduce pressure (after an increase) at times where it seems it shouldn't.  

Am I wrong in my thinking here?  Maybe CPAP mode is a better option?  Curious what others using the AirSense 11 have experienced as it's algorithm in APAP sometimes doesn't seem to make sense. 

I also have Sarcoidosis with some pulmonary fibrosis so obviously that isn't helping matters.

Any other input, thoughts or ideas are welcomed!

[G. Szabo]

I agree with the 11-15 pressure increase. Your minimum pressure should be higher than your median pressure.
If you turn to CPAP, you should increase the pressure even more. For now, you should stay in APAP and gradually increase your pressure with a high EPR setting, reporting the outcome and feeling.

[SeePak]

Hi gr3ggo

IMHO, you are correct that the APAP machine is reacting in differing ways, and that is how it goes with APAP !
There is NO feedback , really, to be able to control properly.

Wave shapes ....Someone out there, please show me your wave shapes and how they have been affected by therapy !?

And flow limitation, you have none !!  
Stop right there...NONE.

So why chase that?

How are you feeling?

Do you awake rested?

Are you tired during the day?

Are you anxious in general?

YOu have a chart, i think (cause i dont see your events), that on the surface, i would LOVE to have.

but guess what, my chart looks like an old used dart board.

But my sleep and rest are becoming awesome.

And even without CPAP therapy now! ( i dont suggest that to anyone, but it is a more and more common occurence going on )

Sleep studies are  done with constant pressure for a reason.
To get to the bottom of where you get the best results.
Then a sleep clinician adds extra range to your pressure settings to cover other discursions, that end up often causing more harm than good.
The internet is littered with these cases.

And i have seen more than a few industry people who use CPAP exclusively, that tells me a lot.

This site is awesome for the Oscar reporting.
Attention to flow limits and wave forms and extra pressure is the norm.

By now, that should show up as awesome results.

I would like to see the data, objectively if possible, but subjectively is your best indication probably.

Regardless of the final settings, i would think we would standardize how we get there.

A narrow band of pressure OR straight CPAP should get us there the fastest.

Dont know why or how this could be that far out there in thinking??

[PeaceLoveAndPizza]

The breathing is very flow limited, just not being counted as it does not meet the ResMed requirements for a flow limitation worthy of incrementing the counter. That does not mean it is not happening.

[SeePak]

Pizza

Yes I see the cone shape of the flow pattern and I believe that would be corrected by having the proper pressure at all times with which would be a probably about 9 cm or so without epr so that it stays there and keeps the airway open you can see how it Narrows and the Machine does not respond that's why the automatic is so bad in these devices.

By staying at a constant pressure the airway will stay open and you will not see that cone flow shape on that chart.

Seems like some Airways are harder to open or stay open than others and once it closes it takes a lot more to open it so what I think happens a lot and so do others out there is that the pressure gets too low which allows the airway to partially close again and high inhalation pressures compounds the problem

to add, having said the above, that chart is one of the better i have seen for not overshooting pressure.
It seems to make a correction, wait stay the same then over time the flow comes back.
And AHI is low so i am thinking this is a simpler case to resolve the apnea that was found.
Like so many of you here say, everyone is different !

And also, it is that algorithm that is used that determines how the pressure reacts, and when you have more going on with breathing issues, it will be doing a lot of pressure corrections, and most or whatever amount are not required etc. etc.

[gr3gg0]

Hi,

Thanks everyone for the feedback.  In continuing to find to proper settings, I'm now at 12-16 with EPR at 3.  As shown I am still seeing the same flow restricted breathing as before, little has changed.

Any input on next steps?  I know one person mentioned CPAP mode so the pressure remains the same.  

Also watching some LankyLefty videos and wondering if this is UARS and whether a Bi-Level would be more effective.  After spending $$ on the AirSense would be frustrating to now spend more on a Bi-Level but if it would make a difference I'd consider it.

Lastly, based on last night's OSCAR, hard to tell if the FL's are causing a ton of arousals thus fragmenting my sleep.  My AHI is consistently low, yet I do not feel refreshed in the morning and wake up (at least consciously) a few times a night.

Curious to hear everyone's thoughts.

Thank you!

[SeePak]

9 min 10 max

Epr0

Constant pressure....9.5 cm. Epr0

See if flowrate loses some of that coning.

[Deborah K.]

Whatever pressures you decide to use, keep the EPR at 3. Turning it off will make your problem worse.