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[CPAP] OA Events preceded by flow spike - Printable Version

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OA Events preceded by flow spike - rhodesengr - 02-02-2016

I was looking at the data for the last few nights. I notice that most of my OA events are preceded by a large spike in the flow rate. So I am curious what that is. Is that like a gasp followed by not breathing for a while? I would think if there was an apnea starting it would be preceded by a decline in flow as the blockage set in. It looks more like a gasp followed by holding by breath.

Attached is a zoomed in view of one of my typical OA events


RE: OA Events preceded by flow spike - Possum - 02-02-2016

That's an interesting observation. I do not have the same patterns with my OA's. Generally my flow rate curve starts having a lower amplitude, like a hypopnea, but then I stop breathing.

Do any of the other graphs reveal anything interesting happening right before the OA? Since your pressure was steadily increasing before the OA, I'm wondering if you were snoring, and that was that last loud snore right before the airway closes. That seems to be a common pattern for those with that cycle of snore followed by an OA.


RE: OA Events preceded by flow spike - trish6hundred - 02-02-2016

Hi rhodesengr,
WELCOME! to the forum.!
Hang in there for more help with your graphs. and much success to you with your CPAP therapy.


RE: OA Events preceded by flow spike - Sleeprider - 02-02-2016

You may be holding your breath. There is a large inhale and no exhalation, on the graph during the OA event, then a second inhale and normal breathing. I would 'guess' you may have exhaled through your mouth, registering an OA. Could be a dream or a yawn, but I doubt you experienced much, if any desaturation. there is just a bit of recovery breathing.

Is this typical, or a one-off?


RE: OA Events preceded by flow spike - rhodesengr - 02-02-2016

(02-02-2016, 07:50 PM)Possum Wrote: Since your pressure was steadily increasing before the OA,

well it looks that way on the zoomed-in timescale but that pressure change is just one of the random pressure test pulses the PR560 puts out. It is not due to anything going on with my breathing. I asked about these pressure spikes elsewhere and was informed that PR machines just do that, i.e. they randomly poke you with a pressure pulse. If you look at the zoomed out graph, there are many of them throughout the night.

There may be other graphs of interest but I think they show the same thing. For example, there is a big spike on Tidal Volume showing a lot of air going in and slowly going down. So that also looks like a gasp before an OA.


(02-02-2016, 08:58 PM)Sleeprider Wrote: Is this typical, or a one-off?

typical of pretty much all my OA events. The spike varies some and I generally only have about 3 per night but I'd say the one I posted is pretty much like almost all of the others over various nights.




RE: OA Events preceded by flow spike - AshSF - 02-03-2016

I would guess that you took a large breath and then tossed and turned in bed and it took you 10+ seconds to settle in the new position. And the machine duly noted this as apnea.