"Odd" Waveform?

[Miss Emerita]

And Rubicon, what is my prize?

Sorry, no prize.

While the second graph is mouth breathing (that poster generated the waveform while awake to try to duplicate the original one), they are NOT the same.

I'm confused -- so what was the first graph?

[robysue1]

Rubicon posted this:

On TOF (not the TOOF) a poster submitted this waveform:



and asked

Does anybody know what may have caused this?

And lazarus brought up a SleepRes V-com device:

Waaay above my pay grade. Sorry.

But my first thought was: 'With stuff like SleepRes V-Com going on out there getting inserted into the circuit, I wonder whether flow tracings can still be trusted to always represent a patient's natural breathing.'

To which Rubicon replied:

Yeah well that thing looks bogus to me, I'll bet you could duplicate whatever comfort they claim by lowering xPAP by 0.6 cmH2O, going to Slimline 15 mm tubing, changing Rise Time if whatever mode you're using has it and/or adding EPR @1.0 cmH2O.

Need some before/after from somebody using it.

So I need clarification: The original odd wave flow from TOF was not from a user using the SleepRes V-com. And Rubicon's response to lazarus's post means that the SleepRes V-com is a bogus looking thing and the claimed results for the SleepRes V-com can be achieved appropriate dial-winging.

And the stuff Rubicon posted about adding a bacterial filter is more about how one would duplicate the SleepRes V-com thingamabob.

Which brings us back to Rubicon's original question: What's causing the original odd wave form?

And the answer is NOT "using a SleepRes V-com."

And given Rubicon's answer to Miss Emerita's idea that it might be "expiratory mouth-leaking", the original odd wave form isn't that either.

I'll do some more thinking about what that original odd waveform might be if I get a chance in between making lasagne (with homemade sauce) and watering plants and planting a few carrot seeds and lettuce seeds.

[Rubicon]

Tell me when you want a clue!

[robysue1]

Asking for more clarification from Rubicon (if he's willing to give it) based on a bunch of flow rate data from my own data from almost a month ago, which is my most recent download.

This first shot shows what I think is my initial transition to sleep at the beginning of the night for March 26:


The OA scored around 23:47:20 is, I suspect, a mislabeled transitional event as I was getting to sleep. For reasons that I don't fully understand, most of the time when I am simply "holding my breath" while awake, the machine is much more likely to score an OA instead of a CA. And I've long since assumed that when I see this kind of thing in my data, it's just a sleep transitional event that "doesn't really count", even if it's an OA.

Now, the interesting thing (I think) is that a pattern very similar to the "odd wave flow" starts up around 23:48:00. Notably, there is no snoring, no flow limitations, and no detectable leaks being recorded with that "odd wave flow." The data you posted from TOF's guy talking about "exhale puffing" has a clear, steady increase in leaks as he's opening his mouth to exhale, and my data does not have that. I suspect that's important and that data was missing from the original OP on the TOF. Am I right?

Next, if my wave flow is truly another example of the "odd wave flow" data, it's important to note that this pattern, once established continues for a pretty long time. Here are some additional snippets of data from the same night.

Picking up where that first image leaves off, we get this set of images:

[robysue1]

And the pattern continues in my data:





And this pattern continues non-stop for another 20 minutes or so, until we get to what I presume is a spontaneous arousal at around 0:22:45:



Interestingly (or maybe not?), what happens after that arousal is a short return to "normal sleep breathing" and then another transition to the "odd wave flow" breathing, as shown in the next two images:





So now for the big ask of hints:

1) Are all of these flow rate charts from my data the same thing as the "odd wave flow" from the OP on TOF?

2) How significant is the fact that my leak rate is 0.0 L/min for the whole duration of the "odd wave flow" breathing?

3) How significant are the occasional snores scored during the "odd wave flow" breathing?

And I'll hazard a wild guess: Is it possible this "odd wave flow" might be tied to some very, very soft expiratory snoring (almost like a cat's purring) with my mouth closed?

[Rubicon]

Notably, there is no snoring, no flow limitations, and no detectable leaks being recorded with that "odd wave flow." The data you posted from TOF's guy talking about "exhale puffing" has a clear, steady increase in leaks as he's opening his mouth to exhale, and my data does not have that. I suspect that's important and that data was missing from the original OP on the TOF. Am I right?

Bingo!

Clearly, you can't simultaneously have leaks and no leaks!

Without the leak data, there's still a way to analyze this...

[Rubicon]

If the areas +/- of the -0- line are =, then the volumes are the same and there are no leaks present:



They certainly look close by eyeball (I suppose exhalation actually appears larger), but I went the additional step of using a "Figure The Area Of An Irregular Shape" app and measured a few and they are spot-on.

So whatz happening...

[lazarus]

Emphysema?

[robysue1]

They certainly look close by eyeball (I suppose exhalation actually appears larger), but I went the additional step of using a "Figure The Area Of An Irregular Shape" app and measured a few and they are spot-on.

So whatz happening...
[/quote]
Definite Integrals! That's what's happening mathematically.

Yes, if the area for the inhalations and exhalations are the same (regardless of shape), that's a pretty good hint that there's no leaking going on.

As for what is going on, I need a hint if my idea of purring is totally off base.

Is it possible this is just a variant of "normal sleep breathing" for some people?

[Rubicon]

Emphysema?

An excellent thought, but I don't think COPD is responsible in these cases.

[robysue1]

Emphysema?

I don't have emphysema. Or asthma. Or any breathing disorder that I know of beyond OSA and seasonal allergies.

Could the answer be seasonal allergies? Cause they've kicked in big time this spring and I'm dealing with a lot of congestion and I'm not taking zyrtec or doing the saline sinus rinses or flonase nose spray (yet) simply because I don't wanna. (And I'm sleeping "ok" right now; not as good as I sometimes do, but decent enough to feel ok during the daytime and not have any of the old hand/foot pain I used to have prior to starting CPAP way, way back when.

[Rubicon]

IMO I'd say the most likely suspect is palatal interference, acting as a one-way valve. If people are wearing FFMs, then it could be a mouth puff. If it's a nasal interface, then partial palatal interference creates a flow restriction which results in a fixed exhalation rate.

We need to add a DISE to our toolbox...

[lazarus]

. . . when someone closes their mouth when they inhale but lets it open when they exhale. . . .

Close enough, then?

[Rubicon]

How significant are the occasional snores scored during the "odd wave flow" breathing?

If you sleep through them, I'd say they're academic. If they create tons of arousals, get the stent or the scalpel.

And I'll hazard a wild guess: Is it possible this "odd wave flow" might be tied to some very, very soft expiratory snoring (almost like a cat's purring) with my mouth closed?

I'd say that's exactly what it is.

[Rubicon]

. . . when someone closes their mouth when they inhale but lets it open when they exhale. . . .

Close enough, then?

Only in atomic bombs and hand grenades.