I captured THE ROSETTA STONE moment, please help decypher it

[koy23]

The flow-rate trace looks like a sigh.  A cough involves exhalation, so I don't think that's it.  A little on-line sleuthing suggests that sighing during sleep is common.  What isn't common is the wake-up problem.  

In the flow-rate graph, I see normal sleep breathing, then the sigh, then several breaths with long-ish pauses between them, then what MAY be a resumption of sleep breathing, or maybe just drowsy breathing, followed by a big ugly wake-up breath.  The elongated pauses are due to the way deeper breathing can wash out CO2, which reduces the drive to breathe until the CO2 level builds back up.  I suspect the big ugly wake-up breath is what you're describing as a gasp.

None of that really suggests a solution to me, though PS can also encourage wash-out of CO2.  Possibly less PS would help you stay asleep or drowsy after the sighs.

I'm puzzled: why does PS go to zero over there on the right of the graph?

After that gasp, I DID wake up, so those few breaths after it is me awake turning towards the machine and accessing the clinical menu and lowering the PS to 0.

[Dormeo]

Got it, that's helpful. So the sigh ("gasp") was the wake-up, you were awake in the few breaths after that, and then produced the ugly breath as you turned to reset the machine. I do still wonder whether somewhat less PS could be of value to you. But I realize you're having the frustration of trying various settings, finding that they work pretty well, and then finding that they don't.

Does this happen during the night (as opposed to a nap) and when you've been asleep for a while?

[sheepless]

"What about that mask pressure spike? Is that him coughing? Or is the machine jacking up the pressure momentarily?"

what Dormeo said I think. I see lots of spikes in my and the charts of others. after a long stretch of nice breaths, it stands out but isn't unusual. if it's not a sigh, I don't know what it is. to me it simply looks like a larger inhale followed by some recovery breathing.

I haven't spent much time with mask pressure so I can't knowledgeably comment but notice the mask pressure line after the flow limited spike after the one circled in red, at ~18:32:58. I'd think that represents a leak but none are indicated and like I said, I don't know how to interpret mask pressure.

it's unusual to have ps set to 0. I've forgotten why you have it there (aerophagia?) but I'm sure you have a reason.

[Geer1]

Congrats you found an example of a spontaneous arousal, blips like that often occur during them.

As I have tried to convey to you in your other threads there doesn't appear to be anything breathing related causing these arousals. Unfortunately you find yourself in the same boat as I am in, poor sleep quality and no known reasons for it. Imo give up on chasing a breathing issue and start trying to make other improvements on general health and sleep quality, doing so has provided me partial improvement and still looking for the last bits. If I had of kept chasing breathing issues I would have never started making progress.

Dayvigo is an interesting sleep aid that has helped me a bit. Might be worth asking your doctor about it.

Edit: Those blips at least in my data and video recordings are just quick little inhales during arousal. Often my eyes pop open at the same time as that quick short inhale like something just randomly woke me up. Sometimes its just a weird little inhale and not an obvious arousal but in this case with the change in breath pattern almost certainly an arousal.

Edit2: By give up I don't mean on CPAP. I mean accept you are treating your breathing issues sufficiently and move on to trying to find other issues and treat them.