[Pressure] Trouble identifying correct pressure

[wantgoodrest21]

Hi All,

I have been lurking silently in the forum for a few weeks now, but lost where to go from here.

Background: I got diagnosed with severe sleep apena in 2016. From 2016 to 2021 I used my CPAP (Resmed 10) off and on. However I am now really starting to see the side effects of not using it consistently. About a month ago I got serious about using it every night.

During my original sleep study (diagnostic portion), I had mostly obstructive but also some central apena as well (50.4 to 0.9 index or 118 to 2 occurrences).

For some reason OSCAR is not able to read my original settings, and it seems to have reset for some unknown reason in September 2020. In January of this year I was doing:

Pressure: 6 - 12
Mode: APAP
EPR: Full time, 3 cmH20

(Attach is a screenshot of a weekly overview, and a sample day)

However I was having quite a bit of CA, or at least I thought it was too much. So I turned the EPR down to 1, which I thought was a common suggestion from other threads I was reading.

Qualitatively speaking, my sleep has tanked since the change. The first night was awful. I was having a ton of leaks (8 events, 4.88%), constantly waking up, and the CA events didn't seem that much better (8 events, 1.43), but my AHI was still good (1.43, I think?). From what I was reading, it can take some time to get adjusted to things. So I didn't touch anything until March 1st. I was reading that perhaps the changes in pressures could make things uncomfortable, and I noticed that my maximum pressure now with the current EPR setting wasn't enough. So I changed it to be 8 - 13, and kept EPR the same.

It's no better even after two nights. Last time felt awful (also attached, March 2nd). I apparently had a large leak for 16 minutes without even realizing it...my partner also commented that I seem to be fighting with it all night.

I'm lost where to go from here. Any suggestions?

Thank you very much for your help.

[Sleeprider]

I would get back to using more EPR and give higher weight to restorative sleep than the numbers. Let's start with 7 minimum, 11 maximum and EPR 2. We have some tools to use to reduce the low-level CA events you experience, but I'd like to get a better feel of some alternative settings. In the two detail charts you posted, we can see that with EPR at 1, your 95% flow limit soared to 0.12 and your pressure weas much higher, being driven by the flow limitations. You also lost tidal volume with the low EPR. Lots of things are better about the chart with EPR 3. CA events tend to be less disruptive to sleep as they represent adequate ventilation such that breathing can briefly pause without really feeling it. On the other hand, excessive flow limitation represents a great deal of respiratory effort which leads to more arousal and fatigue.

A couple of things we may look at if needed are using a more steady fixed pressure or enhanced expiratory rebreathing space (EERS) to increase rebreathed CO2.

[Geer1]

I agree with Sleeprider. Would also be curious to see some 4 minute duration zoomed in views showing central apnea and normal breathing.

[wantgoodrest21]

Thank you both Sleeprider & Geer1!

Made the suggested changes. Attached are the results, and two durations. 

Huge thank you again,

[Dormeo]

In the zoomed-in screenshots, it's easy to see the arousal breathing that precedes and causes the CA. It has a bigger amplitude and looks irregular compared with asleep breathing. The arousal, not the CA, is what might be problematic.

You will get excellent advice from Sleeprider about revising your settings. A few comments from me:

* Always report how you feel during the night and the next. Your numbers are good enough that this should guide revisions to your settings.

* Try to leave a little more room for sleep; experiment, if you can, with 8 or 8.5 hours in bed.

* The next time you post a chart, please include the following graphs:

Events
Flow rate
Pressure
Leaks
Snores
Flow limitations.

You can fit them into a single screenshot by grabbing the horizontal gray bars that separate the graphs and pushing them up.

* Consider turning off the ramp, unless it is important to your ability to fall asleep.

[Geer1]

As mentioned those apnea are post arousal and not real or the issue. The trick is to look at the breathing prior to those apnea to determine if breathing issues were involved or if the arousal appears to happen for no explainable reason (based on OSCAR data, could be things like movement disorders or spontaneous arousal).

[wantgoodrest21]

Thank you all for your help -- I greatly appreciate it.

I turned off the ramp as suggested.

Last night the numbers were good, but I am still struggling to using it all night. This wasn't an issue before with EPR 3...I don't feel like I'm sleeping as deeply before, and constantly tossing around all night. Given that the CA may not actually be an issue, would it be okay to go back to EPR 3? Or anything else I should try?

Thanks again.

[Gideon]

I see no issue with trying EPR=3, o viously monitor the results

[Dormeo]

I hope EPR of 3 will help you sleep more peacefully. Do you have any sense of whether you're disturbed by leaks or pressure changes?

[Geer1]

You don't seem to need fluctuating pressure very much. To help fine tune which EPR is best I would try using fixed pressure and only changing the EPR. This will also get rid of pressure fluctuations which might help as Dormeo hints. This last data at an average pressure of 9 cm looks pretty good so that is what I would use for a pressure.

To use fixed pressure can set min pressure to 9 cm, max pressure to 9 cm. Try either EPR 2 or 3 for a while and then switch it to see which one feels better for you. Results will have to depend more on feel than data.