New issue "missing breaths" on ResMed AirCurve 10 ASV

[schleepyhead]

Hello all,

Long-time ResMed ASV user with complex SA. Recently I have noticed a new problem I can't figure out:

Waking up or maybe already awake barely/groggy, notice myself feeling out of breath, pressure out of the machine feels like it's fallen away, below my EPAP 'floor'. I take a few breaths and don't get any IPAP support. Then, I get hit with a big "backup" breath triggered by the machine. Then things get back to normal and I can sleep again. Not seeing any leaks. A few times with this, the EPAP has fallen so low (by my feel) that I have tried to turn the machine on in my confusion, only to turn it off instead...

Where can I start to troubleshoot this, other than posting on the forum here? Really appreciate any help.

Thanks!

[Sleeprider]

If you download the free OSCAR software, you can see what is going on with a breath-by-breath view of your respiratory flow rate and mask pressure produced by the machine. The Resmed ASV has limited user settings, and it would help to know what your machine settings are, but either way, we would still want to see the Oscar data.

[schleepyhead]

Thank you Sleeprider!

Got OSCAR installed and pulled in the data. Graphs from one night and a zoomed in view are below.

Also, here are my prescription and settings:

Min EPAP 9.0 Max IPAP 25.0 PS 5.0-10.0 (cmH2O)
Humidifier Status On
Humidity Level 4
ASVAuto
Min EPAP 9.0
Max EPAP 15.0
Min PS 5.0
Max PS 10.0
Mask Full Face
Ramp Time Off
Climate Ctrl Auto
Tube Temp 76F
AB Filter No
Ext. Humidifier No
Essentials Plus
Leak Alert Off
SmartStart Off
Press. Units cmH2O
Temp. Units F


Graphs attached for one night and zoomed in views of two "events" that "look like" what I'm describing (to my untrained eye).

   

   

   

[Sleeprider]

The left margin Daily Sidebar of the daily details chart gives us important settings and respiratory information along with the statistics. Please be sure to include it rather than the Events tab.

With EPAP min 9.0, PS min 5.0, PS max 10.0 and max pressure 25, your pressure ranges from 14/9 to 20/10 based on my observation. For complex apnea, I would like to see more than 5-cm separation between PS min and PS max to ensure the machine has some room to fill those missing or short breaths. At 02:24:20 your machine is pushing the maximum PS but not creating enough respiratory flow to avoid the hypopnea marked at 02:24:45. This problem is also visible at 02:23:20 and 02:24:00 leading up to the hypopnea. This looks like typical central variable breathing and would likely be a of CA without the ASV, but is instead incompletely treated flow reduction, that needs a bit more PS to fully mitigate. You can see the same problem at 07:17:10 and 07:18:10-07:18:40.

For now, I think EPAP min looks fine, I would reduce PS min to 4.0 if you tolerate it,a nd increase PS max to 12.0. I think you just run out of pressure needed to mitigate some of the centrals and this becomes an occasional arousal and recovery breathing. Overall, therapy looks good, and EPAP is nearly constant.

[schleepyhead]

Sleeprider: Thank you, thank you, thank you! I made those changes and have had a week with the issues I described resolved. Wonderful. Uninterrupted sleep / no gasping for air waking up in the middle of the night.

Also, the lower PS feels more pleasant. Or maybe it's placebo. Either way, thanks for being a huge help.