Resmed ASV: Lowered AHI, but High Aerophagia

[ar10]

I was diagnosed with severe CSA (AHI 50.6) at the beginning of the year.  I started using a Resmed AirCurve 10 ASV about a month ago.  The good news is that my AHI has consistently dropped below 2.0, and I'm sleeping through more of the night. The bad news is that I consistently have moderate to high Aerophagia. 

I use a chin strap, a full face mask (AirTouch F20).  My AirCurve 10  is set to ASVAuto, with min Epap 5.0, max Epap 15.0, min PS 3.0, and max PS 15.0.

I've attached Oscar charts from the last three nights, which seem to be fairly typical. 

Any suggestions about how to reduce the Aerophagia would be greatly appreciated.


           

[Rich66]

As a user of the same Machine, I'll give you my opinion. Take it for what it's worth. I'd adjust the settings.
EPAP min 4.0
EPAP max 7.0
PS Min 2.0
PS Max 7.0
I would use these pressures and then adjust from there. Your pressures are set high -- like in a default setting. I would say you need to customize the settings to your need and what works for you. Also, remember, "How do you feel" is very important. I've had 0.00 nights and yet still felt terrible the next day. It took time to dial in the settings to where I can feel like a human, and not a zombie. Also, I have lung issues that may affect the final settings which could be different for you.

[Sleeprider]

ar10, your results with ASV are very good, however you are seeing increased comfort due to aerophagia, and this will require lower pressure. I think there is considerable room to lower EPAP max from 15 to 7.0, and this will continue to provide efficacy. You have a very low incidence of UA (obstructive) events and so a 7.0 max EPAP, or even lower should continue to produce satisfactory results. The maximum pressure support is delivered infrequently, and nearly always there is a hypopnea event included in those brief periods of higher pressure support. Hypopnea events in your case appear obstructive and clustered, suggesting a possible positional (chin-tucking) issue that is causing restriction of the airway due to the head-neck alignment. This might be due to sleeping position, tall or multiple pillows or other causes. Your positional apnea is relatively infrequent and I don't think you need a soft cervical collar. Something to look at carefully is the use of a chin-strap can cause the jaw to be pulled back rather than up, and this will cause the kind of airway restriction that leads to these few hypopnea or clusters of restriction.

I think we can reduce the PS max from 15 to 12.0 and not impact your efficacy in therapy, provided you consider that there may be a positional aspect at play and try to deal with it. In summary, I am suggesting ASVauto mode at EPAP min 5.0, EPAP max 7.0, PS min 3.0, PS max 12.0 and evaluation of sources of positional airway restriction, including the chin-strap.

[ar10]

Thanks very much for the helpful responses.  I'd planned to try a soft cervical collar instead of the chin strap to improve my comfort level, and maybe that will resolve the obstructive issue as well.  I'll try that first, and then try lowering the pressures.  Much appreciated!

[ar10]

Sorry, I forgot to ask, when I try setting the AirCurve 10 to EPAP min 5.0, EPAP max 7.0, PS min 3.0, PS max 12.0, how will that affect the IPAP min and max?  Is the formula EPAP + PS = IPAP, or something else?  Thanks again.

[Sleeprider]

The pressure support is adaptive and used as needed, however with the new settings your potential pressure range is 8/5 to 18/7 instead of up to 30 cm IPAP. In reality your IPAP pressure rarely reached 9 cm, but with ps15 you were looking at 24/9, so the proposed settings are a meaningful reduction.

After we see the results of the pressure decreases we can decide if additional reductions are needed or reasonable. The main thing is they should work well in conjunction with positional corrections.

[ar10]

Thanks, again. I really appreciate the help.

[ar10]

I moved the Epap and PS settings down as suggested (Epap to 7/5 and PS to 12/5, which resulted in an Ipap of 8/19). 

The AHI increased slightly, but is still low, and I got a little relief from the Aerophagia.

Thank you very much for the invaluable guidance!

I also adjusted my pillow to try to reduce any neck tucking.  Seems to have helped, until last night, when I put in a new mask cushion.  I think it may not be conformed to my face yet, and leaked a bit.

Attached are the OSCAR readings for the last three nights.

Do you suggest any further changes?

[Sleeprider]

This is good therapy, and a compromise between AHI and aerophagia is a matter of feel, as well as trial and error. You have the knowledge and ability to navigate that better than I can advise from my chair. Glad to see things working in your favor.

[ar10]

Thanks, but I think you're giving me way too much credit for knowledge.  I just started treatment for the first time a month ago.  Are you saying that the current balance between AHI and Aerophagia is about as good a balance as I'm likely to get?  If not, to try to lower the aerophagia further, would you suggest reducing the Epap or PS, or both, and would your suggest adjusting the Min or Max, or both?  Thanks in advance for any further help.