SevereApnea help needed with CA's please

[SevereApnea]

SevereApnea help needed with CA's please

Still trying to fine tune things and likely obsessing because I do feel fine during the day, but am still trying to get to grips with understanding the subtle ins and outs.


Preamble:
Sleep Study 18 Dec 2019
AHI = 40.1
Total Apneas = 58
Mixed apneas = 5
Central apneas = 4
Hypopneas = 119
Central hypopneas = 0
Total RERAs = 0
02 desaturation  to 79%

Titration study: 17 Feb 2020
AHI =  0
Total Apneas =  0
Mixed apneas = 0
Central apneas = 0
Hypopneas = 0
Central hypopneas = 0
Total RERAs = 0
Minimum O2 = 92
So Centrals are not a big  part of my initial diagnosis.

Titrated to 7 cm H2O, no EPR recommended by Physician. Felt suffocating. Pressures too low for comfort.
However, sleep techs all recommended EPR= 3.
This initially led to too low a minimum pressure; hence we have upped these.

I have now settled on Resmed P30i and N30i nasal cushions.
Reading the boards responses to many queries about Centrals and the Optimizing Wiki I have learnt the following:
1. Clearly without thoracic and abdominal bands xPAP machines can only guestimate about Centrals.
2. Central apnea often increases with increase in pressure, but need more pressure to deal with FLs.
3. Centrals often manifest in initial xPAP therapy due to resetting of CO2 drive.
4. Wiki recommends setting min pressure to 2 cm below Resmed Median pressure. I assume this is with EPR = 0.

Please see attached chart:

[attachment=22573]

My set up for the night = Neck collar, mouth tape, Resmed P30i Medium.
Ramp 7.6 Min 9.6, max 11.6, EPR =3
Obviously, I am happy with this state of affairs, but am still interested in comments about this chart:
I will post the close up of the events in the next posts, individually labelled CA’s, 1 – 6.

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[SevereApnea]

Numbers 4, 5 and 6.

[attachment=22580]
[attachment=22581]
[attachment=22582]

Q1. Do the board members agree that these are true CA’s or just SWJ?

Q2. I have been on PAP since 23 Jan: is this enough time to reset the CO2 drive?
Q3. If I aim to reduce these CA’s should I
 
a. do nothing and just wait.
b. reduce max pressure in an attempt to get rid of the CA’s, or
c. reduce the EPR to 2 or even 1?
d. go back to CPAP (min = max at say 8 cm H2O with EPR off)?
 
I am also looking at my Flow Limitations: I understand higher pressure can improve this.
If I reduce max pressure will this mess with my flow limitations.

[SarcasticDave94]

Although you did not have a predominant amount of CA on your initial study, you did have 4 CA. BTW predominant and other CA types enters into the conversation when one has lots of CA that doesn't respond to regular CPAP therapy. To me, predominant indicates 50% or more CA to OA, in regards to attempts to get an ASV for example. Just having 4 means to me I would watch that event count.

Cause and effect: I think you will need to connect CA events to how good or bad your therapy does, as in you feel better if CA is lower or it has little to no effect on how you feel. You need to connect this relation if it exists, and note if/how it does exist. Track how it makes you feel. Does it affect sleep quality? How?

My understanding on addressing CA with any machine other than an ASV would require a minimal of pressure swings. This can be by limiting EPR in a ResMed or Flex in Respironics, working to eliminate Ramp, and getting an optimized pressure settings that changes as little as necessary.

FL/flow limit: more pressure reduces these events, these can be hard to reduce for some, only focus on these if you know they hinder sleep quality.

Bottom line from a guy with predominant/pre-existing CA at ratio of 24 OA : 124 CA
Do all you can to make CPAP therapy optimized/perfect while eliminating/reducing as many CA events as in your power. If you can't reduce the CA, and if they hinder sleep and rest, you need to know how to tell a doc that will work with you to do something about it. That would mean you build a case for ASV if it hinders sleep, but with only 4 CA on the study, it's an uphill battle.

[SevereApnea]

hanks Dave, always good to get insight from others.

I have kept my pressures a little higher than titrated for, for medical reasons that I hope to have some good news about in the next couple of  weeks.

Then my plan is to titrate down my pressures, and as you say, to reduce the swings, or reduce the range.
I do find EPR feels better with expiration and already find myself with catch up REM: being more aware of dreams that I previously never thought I had!

Up to now I have been focused on reducing OAs, but will include CA's in my comparison with my Quality of Sleep.
More homework!


You said:
"Bottom line from a guy with predominant/pre-existing CA at ratio of 24 OA : 124 CA"

Wow that is a high ratio.
I have been looking at the CA's mainly to try and understand how the xPAP flags them and does so correctly.
I have assumed, up till now, that it is the OA's that make one feel bad the next day, and not the CA's.

Are you saying you can feel worse from your CA's than from your OA's?

This is a complex world, this sleep business!

Yes I will be seeing my sleep Doc early June, (yikes that's next month!) and can take these things up with him then. I don't anticipate needing anything other than my Autosense 10 at the moment, but who knows what the future brings.

[Gideon]

Both OA and CA disrupt sleep and REARs definitely do, as also do lessor events to a lessor extent, hypopneas and and at the low end of the pole flow limits.

On ResMed flow limits are especially important as they are a primary driver of pressure increases.

You can think of CPAPs sending "sonar" pulses to see if airway is open or closed to determine if Central or Obstructive. These are considered accurate for diagnosis on CPAP machines.

[SarcasticDave94]

I see any apnea event, Central, Obstructive, Hypopnea, (even flow limits for some) noting that these events can be a cause of disrupted sleep. It depends on the individual how disruptive the different flavors of events are perceived. That in turn shapes your actions and needs to be used to shape the docs actions IMO.

[SevereApnea]

I am still just wondering which of these are true/false CA’s or SWJ?

CA1 is preceded by what I assume is an arousal: disrupted Flow Rate, then increased pulse rate, then the so-called CA, then a fall in O2, then Flow Rate returns to normal.

CA 2 is different: first the Flow Rate decreases, no change in PR, O2 remains stable, post CA there is an increase in Resp rate, presumably blowing off some CO2?

CA 3 follows a true OSA. First there is an arousal, Flow Rate increases, PR goes up with the OA, Flow Rate tapers off while O2 goes up, THEN there is another CA. I interpret this as blowing off some CO2 which then causes CA 3.

CA 4 is like CA#1: arousal, increased Flow Rate, PR goes up a bit, CA follows, but O2 never falls.

CA 5 is preceded by disordered Flow Rate, then increased PR, then a rise in O2 then the CA#5, then Flow Rate slowly tapers down.

CA 6 is preceded by normal Flow Rate stable PR and O2 and appears to come out of the blue.

So there is some variability with these CA’s. I figure some must be SWJ. Without true PSG data some of this may just be  an educated guess.

I also note looking at many of my charts that many CA's tend to come when the Autosense starts to lower the pressures, ie on the downward slope of the curve. So variability of pressure somehow messes with CO2 / O2 regulation of Respiratory Drive.

At the end of the day, I am just so grateful to have far fewer true OSA’s than prior to xPAP therapy!

[SevereApnea]

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