Traded OSAs for CAs during home APAP trial - What next ?

[alshayed]

I agree with Sleeprider that you should try changing around the EPR settings. Personally with my DreamStation (so not directly comparable to your Airsense) I found CA's went down when I changed the flex setting from a-flex @ 2 to c-flex @ 1. Some people seem to have good luck with their initial settings but others have to tweak the settings around to find the right combination.

[Stom]

Sleeprider wrote:

Our CPAPs are ventilators, and when we introduce EPR, we are using bilevel positive air pressures with different inhale and exhale pressures, i.e. pressure support.  Even though the Airsense 10 pressure support is limited to 3-cm, in sensitive individuals, this can create hypocapnia and induce centrals.  A few individuals may experience the onset of complex apnea with just fixed simple CPAP pressure with no pressure support, but as pressure support is added to therapy, the chances of triggering complex apnea becomes considerable greater in sensitive individuals.  Treatment emergent complex apnea may reconcile as the individual adapts, but in others, a more sophisticated therapy (ASV) may be required to treat both the obstructive and central apnea. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3700705/

Thanks for the details :-)

Just got back from the RT. She continued my titration on the Airsense 10 loaner and changed the settings to see if my results will get better in an other week. She says it takes the body a while to get used to breathing on an APAP and attributes my CSAs to that.

Old --> New
7-20 --> 6-20
Full Time EPR 3 —> Full Time EPR  2
Ramp ## min (I don't remember - I turned it off because it was annoying), start at 44—> Ramp 25 min, start at 5

The RT was surprised not only that I had the ResMed data on my computer but also at the resolution. It seems that the local Kaiser RTs only use the low resolution cellular AirView data. She apparently made all of her recommendations based on summary data, and considered going from 22 AHI (all obstructive, they say)/RDI 34 to 10 CAI to be good results and that anything under 15 CAI (I think CAI as opposed to AHI, don't remember for certain) to be sufficient to stay on an APAP. She also dismissed many of my CAs as being possibly open mouth, awake or asleep - without looking and the flow graph. I showed her zoom in on the flow graph of a cluster of periodic breathing, which she said looked like Cheyne-Stokes, but made no other comments about it.

The RT also believed "obsessing" over data is bad. I do see her point to a certain degree since daily data is variable and I'd think it can be easy to over react to to naturally variable data and miss the real trends, and it's possible to get freaked out about data one doesn't really understand. But she also seemed to think looking at one's data in detail negatively affects therapeutic results while sleeping - which I'm a bit less inclined to accept at face value and seems kind of the opposite of what seems to be the philosophy of the Apneaboard.

I'm hoping I don't fall in the in between - not getting good sleep on APAP but below the threshold for an ASV.  I'll know more in a week. :-)

[DeepBreathing]

Different rules in different laces, but I would have thought a persistent central apnea index of 10 or more was a prima facie case for getting off APAP and on to ASV.

Did you perhaps get the impression your RT doesn't want to "obsess" with data is maybe because she doesn't understand the data? Let's consider another disease which many of us are familiar with - diabetes. Would a doctor say "don't worry about regular blood tests because that's 'obsessing' about the data? Don't worry what your daily sugar levels are, because that's just data"? I think not. These machines are designed to provide all the data because the data is useful in diagnosing and treating the disease. To just blow it off like that sounds like either laziness or incompetence to me.

periodic breathing, which she said looked like Cheyne-Stokes

No, it's not. Cheyne-Stokes has a very distinct waveform, which your charts do not show. If you really had Cheyne Stokes she should have referred you to a specialist.

[Sleeprider]

Your RT is doing her job. Her acknowledgement of the fact you have periodic breathing that resembles Cheyne-Stokes and an excessive rate of CA events I can agree with.  I don't agree her changes to 6-20 with EPR 2 will make much difference...do it anyway so you can prove it.  You have complex sleep apnea and I don't normally expect an event rate like yours to resolve through CPAP alone.  My suggestions to turn off EPR are based on trying to help you minimize CA events.  The solution to your problem is to obtain ASV therapy sooner than later, so minimizing events may be counter-productive.  Be patient and remember failure is the fastest path to success. 

I think your RT is dead wrong. She is hoping this will just go away and she is playing the insurance game.  At some point and should be making a more constructive effort to move you towards effective treatment.  Give her settings a go, and be sure to follow up next week if it makes little difference.  The lower EPR may help a bit, but I don't see this as a solution for you.

[Stom]

Cool. Thank you both.

I'm in no hurry to shell out cash for an ASV - something sufficiently rare and expensive Vendor Number 1 doesn't even list them :-0 An ASV would be ridiculously expensive, but I am thinking one would be less expensive than rushing into buying an APAP that may not fit my needs and then having to buy an ASV. So I want as much test time as they can give be before they make up their mind and write a script and say see ya later.

I'm going do as Sleeprider suggests and go with the RT's settings and see how they shake out and use that info as a launch pad for next steps. Even though I do like the experienced RT, and even her brusque manner (you don't have to guess what she's really thinking), I do think she has a standard plan she's following based on just summary data.

No, it's not. Cheyne-Stokes has a very distinct waveform, which your charts do not show. If you really had Cheyne Stokes she should have referred you to a specialist.

That is what seemed odd to me. I'd have expected her to say something like, "Oh, those are definitely not state change centrals. They look a bit like Cheyne Stokes, but don't worry, looking at the flow graph it's clear they are not." I think I caught her off guard. It was pretty clear she hadn't looked at of any the centrals in the flow graph, or, if so, certainly not zoomed in.

Attached is a redacted version of the report she handed me at the conference, saying my scores looked good. You can see what the priority is:  Compliance. The only bar graph is for compliance. And in spite of what the report says, my O2 did dip below 88, but briefly only during clusters, which apparently rounds down to 0 minutes (I'm not worried about that dip, but it does show me how summary data can round off the details.)

[Sleeprider]

I think your attitude is perfect. You are ready for the therapy to be successful, and patient for those results, but critical enough to call out a problem. ASV is an insured device if you have good insurance. If not, we can help point you to some "much less than retail" solutions. I'd rather see your medical team get onboard if the centrals persist, and provide appropriate prescriptions, support and care.

[Stom]

Well, this week is better than last week :-) Still not restful (especially last Saturday which was utterly miserable), but the CSAI is down on average, though I can't be sure at this point if that is a real trend or variability. I expect at the coming Friday meeting with the RT she will point to the summary data for last week and the summary data for this week, declare the AHI a downward trend on those to data points and offer me a script for an APAP at the current settings. (This is just a WAG on my part, of course.) So the question I have is whether I should accept and just go ahead and buy an APAP (no DME coverage) and go with it for a few months, or ask for more evaluations of some sort, and if so, on what basis?

I'm not quite sure of what the objectives are for treatment. I wanted to sleep better. I'm not. As long as I don't have O2 desaturation with untreated apnea, what is the point of treating it if my sleep is worse with treatment than without?

[Sleeprider]

Please turn off EPR. If that doesn’t work this thread has a really promising approach to therapy onset complex apnea http://www.apneaboard.com/forums/Thread-...some-sleep

The only other suggestion I have is to do an end-run around the RT and talk to your doctor. COAP in its current configuration is a failure.

[Stom]

Please turn off EPR. If that doesn’t work this thread has a really promising approach to therapy onset complex apnea http://www.apneaboard.com/forums/Thread-...some-sleep

The only other suggestion I have is to do an end-run around the RT and talk to your doctor. COAP in its current configuration is a failure.

Thanks. I take it you don't think the better results over last week are sufficient to consider the APAP treatment successfully titratated (if that will even prove possible) to justify them handing out a script for me to go off on my own rather for than to keep evaluating. (This is, I think, on of the areas the board helps provide context since i really don't have any outside my own experience.)

I'm definitely interested in trying the EPR off and the ramp off or left at therapeutic pressure (since that is pretty low) so I can breathe easily. I wonder if the ramp is on set at the same level as the therapeutic pressure if the EPR on ramp only setting could still be used to ease into the EPRless breathing? Or am I thinking in too tricky a manner?

And the methods of providing more dead space/CO2 to support breathing reflex sound interesting (though I'd think one would want pulse ox monitoring when trying such a thing).

[Sleeprider]

I think it's worth seeing if removing EPR can bring you closer to the goal. The Enhanced Expiratory Rebreathing Space (EERS) stuff makes a lot of sense for individuals that do not have central sleep apnea in diagnostic tests, but develop complex apnea with therapy. The risk of oxygen desaturation is actually pretty low. Your tidal volume average of 440 mL with a dead-space of 60-100 mL would likely restore respiratory drive to background levels while eliminating OA at relatively low pressure. If you decide to experiment with it, just buy the $20 swivel/vent and attach it between the CPAP tube and your N20 hose for 70 mL of dead space. If that works, then fine. If you need more, then a 6-inch section of corr-a-flex cpap hose is pretty cheap (order at thee time to save shipping), and provides another 58 mL. You should not damage your mask vent, just tape over the the vent holes temporarily. The pressure and lack of apnea maintains O2 safely, while the dead space prevents excess purging of CO2. Excess CO2 will cause hyper-ventilation and prevent hypoxia, so the natural feedback loop prevents low oxygen levels.

Your first step in that goal is to eliminate EPR. Only go to EERS if that fails to resolve CA. EERS is experimental, even in the case of Firefox and is not an approved FDA application, but it makes a ton of sense. If I was in your place I would try it, but I'm a risk-taker, and you should follow your own judgement. I'm pretty excited about the possibility of this technique avoiding ASV in some cases.