Question on Centrals

[Gary.]

Hey all - I'm new to the APAP and I'm trying to figure out if I'm doing something wrong with the machine settings or mask. I'm getting no Obstructive events however quite a few centrals. I can only tolerate the machine for a couple of hours at a time, and still in that short duration I'm getting them.
And I feel worse since I started using the machine than before quite frankly.

Any thoughts, feedback or anything that can help at all?

Happy to post different charts and time intervals if needed, Snore is always blank fyi.

Thanks in advance!

[SarcasticDave94]

A few things about what you've got going on:

We don't see the statistics of your sleep study. Specifically, we need to know event type and count. It can tell us if the CA present are treatment emergent, pre-existing, or idiopathic.
Some CA facts if these are treatment emergent: these CA should reduce within 3 months, all CA events are consistently inconsistent, reduction of pressure swings can minimize CA.

Your settings are a bit counter productive. You have a low pressure setting of 5 and an EPR of 3. This machine can only go to a low of 4, so you cannot receive the full benefits from the 3 EPR. In order to benefit, you will need to increase the pressure from 5 to 7. Regardless of EPR, most adults require a minimum pressure of 6.

You should review the wiki on OSCAR charts to organize to the standard view. If zooming in on specific event flags, it needs to be about a 2 minute zoom level typically.

[Gideon]

Set your min pressure to 7
Set your EPR = 1 fulltime.

On 1 may you EPAP pressure was about 7 so let's set it there and for comfort.
Set EPR = 1 to minimize centrals. Also your 3rd chart shows a reduction of centrals so to continue the trend.

Tyy it then repost.

[Gary.]

Thanks Dave!
Here's a 2 minute interval - and sleep study attached. Essentially it was an at home study and I dont believe it tracked CA (but I may be wrong on that). it showed low AHI but higher RDI..
The few times that I've used the machine I see no obstructives and only Centrals pretty much

After the first few nights the doctor asked to lower the settings to Min 4-Max 8 and EPR full time at 2 -- because I had a hard time breathing out, exhaling against the machine, but it hasn't felt better or made a difference in the centrals for that matter

[Gideon]

Your min should be not less than 4 + EPR with only rare exceptions, it can be higher. This is because EPR can lower the pressure to below the Min setting but never less than 4. Thus with a min pressure of '7', less EPR of 3 and you have an exhale pressure of 4, the lowest possible.

In your case try a min pressure of 7 and an EPR of 1 to minimize central apneas. If you have trouble exhaling we would increase EPR to 2, and maybe even 3.

And I don't see any sign of centrals being monitored in your study either.

The RDI tells me to watch for UARS and Flow Limits being a problem.

[Gary.]

Your min should be not less than  4 + EPR with only rare exceptions, it can be higher.  This is because EPR can lower the pressure to below the Min setting but never less than 4.  Thus with a min pressure of '7', less EPR of 3 and you have an exhale pressure of 4, the lowest possible.

In your case try a min pressure of 7 and an EPR of 1 to minimize central apneas. If you have trouble exhaling we would increase EPR to 2, and maybe even 3.

And I don't see any sign of centrals being monitored in your study either.

The RDI tells me to watch for UARS and Flow Limits being a problem.

Thank you Fred!
Honestly last night with the min set at 4 and epr at 2 and I still had trouble exhaling and felt like fighting the machine. Raising the min and lowering the epr Im guessing is going to make that worse. 
Noob question: can you elaborate a bit more on your last point about the RDIs pointing to a problem potentially with UARS and flow limits? 

This whole thing is all new to me.

[Gideon]

RDIs, Flow Limits, RERAs, UARS , Hypopneas, and even snores are best treated with a pressure difference between Exhale and Inhale pressures. With your machine we do that with manipulation of EPR. With a min pressure of 4 we cannot do that, we cannot even set you up better for comfort. RDI means RERAs which are a series of flow limits ending in arousal.
UARS is indicated with high RDI and low AHI.
Thus I mentioned that.
Your treatment will be a balance between your centrals and your obstructive events.

[Gary.]

Thanks Fred! That makes sense. 
I barely ever get obstructives so it’s all centrals mostly. EPR is the only tool we have for that right? Sounds like this isn’t even the right machine for it

[Gideon]

That is correct, but we need to see what we get. A form of Central apnea is Treatment-Emergent and if that is the case here it should significantly decrease over 2-3 months.
This is frequently caused by the EPR being high and increasing the efficiency of your breathing. This includes clearing more CO2 out of your blood thus reducing it to below your apneic threshold causing central apneas.

If this doesn't clear up we need to qualify you for an ASV machine, the only one that will actually treat central apneas.
Your's may not be this form, but the test is to reduce EPR, we may try EPR = 0. If EPR reduction doesn't clear up your CA events we will definitely add it back in for comfort, If needed we may do so anyway. Failures are what will qualify you for an ASV.

[Gary.]

So I've tried with min 6.8 and max 8, EPR at 1 and have gotten very similar results, even in short afternoon naps I get similar rate of centrals. Here's a 2 min section screenshot. Would you recommend trying with EPR off next? Does anything else jump out at you?
 
FYI, There were 2 obstructives that occurred at the end but they're not real..I was awake by then and holding my breath to see what/how machine would react so those can be ignored