Please Review The Data & Give Recommendations

[Hojo]

I have had 5 excellent nights on ASV, my AHI have been 0.45, 0.83, 0.74, 0.14, 0.97, I'm happy.  My DX as with Central Apnea and the only time I have OA is when wearing the mask; chin tuck.  Once I put on the cervical collar the OA goes away. 

Last night I decided to try the ASV without the cervical collar (up until this week I've been on CPAP).  The first two things I noticed was that I did not have any OA events, and the second was my AHI went up to 3.89, while it is effectively "treated", it is much higher than the other 5 nights.

I'm not sure why the AHI went up, but my first guess is because I wasn't wearing the collar.  Then what I'd like to know is why didn't the ASV take care of it better, perhaps the PS is too low (2.8 last night) and/or the EPAP is too low (4 and not 5). 

I don't want to 'over treat' myself, and yet I also want to know the limits of the machine.  With all this being said, I'm not showing this to figure out what I need to do to the settings, the first is to go back wearing the collar and make sure I get the same results as the first 5 days.  What I want to be looked at, is, why the slow response, help me to understand the machine better.

Thanks

https://imgur.com/a/J4j6H

[Fixit50]

I think you are correct that you are still "treated" even with the AHI=3.89 and that the higher AHI without the collar is cause and effect likely due to an increase in flow restrictions without the collar. I have seen this several times in my own experiments.
Can you add a view expanded around the 3rd hypopnea following 23:00? This would start at around 23:08. Another one starting at 4:39 would also help.
I'm sure Sleeprider can give additional insights but the two additioinal expanded views will also help.

[Sleeprider]

Fixit50 nailed it.  just compare the median and 95% pressures between the two charts.  Huge difference in the therapy pressures.  Well done fixit!  Flow limit appears to be similar, but something was different to increase pressure that much. It might be worth further checking the data and seeing if a lower EPAPmax setting would help. High pressure has never been your friend.

[Hojo]

FIXIT50: Here are two more zoomed in data points; I didn't have any HA events at 4:39, did you mean 01:39?

One thing I forgot to mention is that I woke up breathing through my mouth (I wear a FFM, F20), but this was not just a simple breathing through pursed lips but a wide open mouth, which I thought was a bit odd for me as I don't recall ever waking up knowing that my mouth is open or closed.  It immediately made me come to my senses (awake enough) that if I had the collar on, my jaw may not have dropped open as much and I may would have prevented some mouth breathing had the collar been on.

Sleeprider: So from I'm reading into your comments, you are saying that (as FIXIT50) and what I suspected, the collar helps keep my pressure low(er) and I will respond better to a lower pressure....I have a lot of data points that how the higher the EPAP (CPAP), the worse my RR and TV is. 

I'm still happy with last night but just a bit shocked I didn't see OA events like I normally do without a collar, oh, live and learn.

Thanks

https://imgur.com/a/NFJYg

[Fixit50]

Sleeprider: You said: “..Well done fixit!..” Hey, I had a good teacher!!
Hojo: Thanks for the added zoomed points. Actually, I was interested in a zoomed expansion at 4:39 just to provide some insight into what is going on under different conditions. I thought 4:39 was a good choice since the resp rate went higher there. Might lead to a dead end but never know till you look.

[Hojo]

Is this the time zone your looking for, I may have the two minutes flipped.

https://imgur.com/a/EfyYh

[Fixit50]

That’s what I was looking for. I was hunting around to see if there was anything that could be learned from the flow rate but it all looks good to my eye anyway. Just more good news I’d say. The fact that IPAP made it up to 25 last night shows that the absence of the collar does affect your airway in the direction of more restriction. This is not surprising. I have a similar dramatic change in pressure with my Autoset when I use a chin strap or a mouth guard in conjunction with my F10 FFM vs the F10 alone. The pressure difference is big, similar to yours compared in post #123 above. Of course, I respond fine to the high-pressure condition where I think that’s not true for you. I think pressure support is your friend (I wish my machine had it). If the goal is to adjust the machine such that you can minimize hypopneas or events without having to use the collar (a good goal if for no other reason than to explore the limits and capabilities of the ASV) I suspect you can make some headway via the adjustment process which you are just scratching the surface on presently. As far as how to best go about it, I’d defer to Sleeprider on that. I’ve never been lucky enough to have my hands on a BiPAP or ASV.
BTW, how do you find sleeping with the collar? Is it confining or uncomfortable? Easy to get used to or??

[Hojo]

I have absolutely no problem sleeping with the collar but I will admit that it is much smaller than one that would be used for a neck injury.  I picked up a spare from a store so that I could pack it with the (at the time, CPAP) carrier, the collar was 'fitted' to me and it was so big, it felt like my head was being pushed upward too much, hence, I took it back.

Last night was a near perfect night, AHI 0.27, but I would like to see which one is me breathing and which is the machine.  At 00:16 the mask pressure changes drops dramatically.  I'm wondering if that is where the machine stopped breathing for me and I took over with my normal respirations.

https://imgur.com/a/i2Xbn

Sleeprider:  Previously you mentioned that you thought I should start with a PS of 2, I was told to start at 3 and I've dropped it to 2.8, does it look like I can take it down more?

[Spy Car]

I'm pleased to read that ASV is giving you the results we all hoped for.

Congratulations!

Bill

[Sleeprider]

Hojo, near the beginning of that last graph, you are breathing at 8-9 BPM with significant pressure support. At the last half after 00:17:00 you are at 12-13 BPM without significant pressure support. I learn something everytime you post these graphics. Somehow the machine keeps adapting to your needs. I don't recall any time that you had such regular and good looking, symmetrical respiration, especially the graph you posted before this one.