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Fixed pressure v. auto - Printable Version

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Fixed pressure v. auto - Emmet - 02-25-2018

On 14 Feb. I switched from a fixed pressure of 10 to Autoset 5-15. I think I rather prefer the numbers and trends prior to the change; perhaps I should've left well enough alone.
I'm going to switch back to a fixed 10 cmH2O with no ramp, and see how it goes.

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RE: Fixed pressure v. auto - Sleeprider - 02-25-2018

You replace a fixed pressure of 10 with 5-15. Maybe reset that auto pressure to 8-12? I don't know why the broad range, but I definitely feel you can get auto pressure to work with the right parameters. What is your EPR set to?

RE: Fixed pressure v. auto - Gideon - 02-25-2018

Of significance, your Clear Airways went up.   And they were present at a fixed 10 cmw

Please post your daily charts from Sleepyhead, (see the Organize link in my signature.)  From the above day will be fine.
You may be presenting complex and or Apneas.
In addition to the dailys I'll ask for a zoom in 2 minute segment of your dailies centered around some Clear Airway (CA) events.

This info will allow us to much better help you.

I'll also suggest that you set your range much narrower in your case.  To 8 (2 cmw below your fixed) to 11 cmw (just above your fixed pressure)  (8 - 11 cmw)
Repeat the dailys with the new settings.

Fred

RE: Fixed pressure v. auto - Emmet - 02-25-2018

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RE: Fixed pressure v. auto - Sleeprider - 02-25-2018

I tend to agree with Fred's original hunch that your apnea may have some complex characteristics. You are using EPR full-time at 3, and that can significantly aggravate central apnea events. Were you also using EPR at 3 with fixed pressure at 10?

In your case, you clearly did better on fixed pressure, and we often coach users with complex apnea to use a fixed pressure, generally with low or no EPR.

RE: Fixed pressure v. auto - Emmet - 02-25-2018

(02-25-2018, 03:30 PM)Sleeprider Wrote: I tend to agree with Fred's original hunch that your apnea may have some complex characteristics.  You are using EPR full-time at 3, and that can significantly aggravate central apnea events.  Were you also using EPR at 3 with fixed pressure at 10?  

In your case, you clearly did better on fixed pressure, and we often coach users with complex apnea to use a fixed pressure, generally with low or no EPR.

Yes; EPR at 3 w/ 10 cmH2O fixed pressure.

RE: Fixed pressure v. auto - Sleeprider - 02-25-2018

Well, the trend speaks for itself. I would without question, go back to fixed pressure in your case. I think within fixed pressure, you can experiment with optimization. For example, to reduce CA, lower pressure and less EPR may help. For OA, higher pressure or less EPR. For Hypopnea, the EPR is beneficial. Every change you make, may affect another component of your sleep apnea, so I would go slow and decide what you want to accomplish before making changes. Based on the overview of your pressure before changing to Autoset mode, I think 10 cm pressure with EPR at 2 may be a winner.

RE: Fixed pressure v. auto - Gideon - 02-25-2018

I wanted to originally say to go back to 10 fixed but I wanted to see your charts and hope that Sleeprider would look and see what I suspected (Thanks Sleeprider).  


I'll agree with SR, Set your range to 10 - 10 cmw ( Auto mode to emulate Fixed CPAP ) with an EPR of 2

Try it for a night or two then post results in this thread and we will work on helping you to optimize your therapy.

Fred

RE: Fixed pressure v. auto - Koolbreeze - 02-25-2018

Funny how things work different for different people. I too was on 10 fixed originally and was getting good results with that. Started experimenting with auto mode and now I get excellent results with 9-12 pressure and a full time EPR of 2.

RE: Fixed pressure v. auto - Emmet - 02-26-2018

Thanks; I'm deeply grateful for the help.
Odd; when I first set the EPR to 2, I was a little shocked by how much resistance I had to exhale against. When I awoke, I was surprised by how comfortable it breathed; like it wasn't there.

10 cmH2O/EPR 2cmH20/Ramp off
OA: 1
CA: 42
H: 5

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