New VAuto, need help with settings

[Sleeprider]

You may need a thinner or shorter collar. What brand and size are you using? The pattern of events still looks like positional apnea, and it may be the way the collar is fitting or pushing on your neck, or you may be finding a way to chin-tuck with the collar on.

[nininho]

It's a local brand and the size is about 20 inches length, 3 inches height, and 1 inch thick (50cm x 7.5cm x 2.5cm)

[nininho]

I bought a new collar but the height seemed too high also, so I cut it to about 2 inches(5 cm).
I used it for 2 nights that I attached the Oscar charts here, the first night it was a little difficult to sleep with but the last night it was ok to sleep with, but from the charts, it didn't help on the numbers.

Those hypopnea events weren't common without the collar, so I added a zoomed area with them.

[nininho]

Hi,

I bought a new pillow that supposed to have better jaw support (photo) that I have been using since December 5. There were a couple of good nights and then it seems to have come back to the normal nights. 
   

It seems that the clusters of events have been reduced but since that wasn't constant I believe that there wasn't really an improvement for the new pillow.

My real question is that I've noticed that even when normal breathing the amplitude of the breathing seems to be continually going up and down. Is this a normal breathing pattern or it should be a flat line on top/bottom?
         

[staceyburke]

The going up and down is inhale and exhale...  You need to zoom in more to see each breath and look at the shape to see is there is anything different than normal.

[Sleeprider]

Oscillations in tidal volume can be a reflection of instability in your CO2 levels, and with the CA events a slight decrease of pressure support may be in order. As far as OA events, they clearly cluster in pairs, so you are getting your chin under whatever support you are currently using. It's not very severe, but something to work on.

[nininho]

Is there any problem with this instability of CO2 levels? Is there anything to be done?

I will decrease the PS value for the CA events.

[Sleeprider]

The decrease in PS will accomplish both objectives and stabilize respiration as well as reduce CA.

[nininho]

I decreased the PS by 0.2 and used this for the week.

There were some nights that the CA decreased like these:
       

But there were other days that it stayed high
   

I think I should decrease the PS again to test.

[Sleeprider]

A decrease in PS or finding a way to increase re-breathed CO2 may be options. You might want to read the Enhanced Expiratory Rebreathing Space (EERS) wiki. Not suggesting you use EERS, but understand how CO2 plays into respiratory drive.