CPAP machine weirdness

Factual Questions
1

I have sleep apnea.

I am treating it with a CPAP machine.

So far, it’s working fine. It took me some time (and a smaller, lighter mask) to get used to wearing the thing, but now I sleep with it on, no problem.

But there’s this one little thing that keeps happening that puzzles me, and so I thought I’d consult the superlative minds here on the SDMB and see what they thought about it.

I’ll be lying there with the CPAP machine providing the positive airway pressure, and suddenly I’ll sort of… expel… a bunch of air. I’m not sure how else to describe it. My throat twitches and some reflex action kicks in and what feels like a ball of air comes out of my mouth, often with signifigant force (enough to pop my close mouth open).

It’s completely painless. I’m certain it’s not a belch or anything of that sort. I’m not gagging. It’s definietely something happening in the trachea, not the esophagus, and other than startling me fully awake sometimes, it seems harmless enough. I’m not worried about it.

But it’s more than a bit weird.

The nearest I can think is that the forced positive pressure in my throat somehow “tickles” something in there, and occasionally that tickle gets bad enough that my throat gives a bit of a twitch, like a horse twitching off a fly.

I never feel it coming, though. It’s always a total surprise.

Anyone have any theories?

2

As far as the “ball of air” goes, that sounds like what happens if I open my airway then mouth with the CPAP on. It’s just the built-up pressurized air going out through your mouth rather than your nose.

IOW, you open whatever the little “valve” doohickey back there is, the one that switches you from nose-breathing to mouth-breathing. Then a second later, you open your mouth. If your CPAP pressure is high enough and you’re relaxed, I’d imagine the air pressure would be enough to pop your mouth open by itself. The “ball” effect is from air pressure stacking up until you open your mouth.

Does that make sense? I’m not sure how to describe it, but I can make it happen at will.

I’m not sure what’s twitching to cause the unintentional changeover, though. I’ve not had that problem.