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Wulfman... wrote:
Exactly what I surmised.
For whatever reason, your Flow Limitations and Respiratory Rate increased (and maybe a little snoring)......."dreaming", maybe......and then your pressure started chasing the FLs and you had a "runaway".


Den

whatever reason ... That is exactly what I am trying to find out ... why is the FL graph like that? What causes FL to increase?
BTW, I tape my mouth to prevent mouth leak ... could this have anything to do w/ FL increase? I didn't think so ...

Thx.

unknown12345 wrote:why is the FL graph like that? What causes FL to increase?

Flow limitations
Flow Limitation is a partial obstruction of the airway as detected by a change in the shape of the flow signal.

Sometimes fairly easy to see if you look at each breath individually.
While this guide if for ResScan the basis for FL graphing is the same no matter which software is used.
http://www.apneaboard.com/ResScan_Inter ... -Guide.pdf
main interpretation stuff begins around page 31 and some case studies begin around page 55
I think there are some FL examples explained in there somewhere.
and page 73 shows some examples

To view in SleepyHead you have to zoom in real close so that you can see each breath's shape.

unknown12345 wrote:

Wulfman... wrote:
Exactly what I surmised.
For whatever reason, your Flow Limitations and Respiratory Rate increased (and maybe a little snoring)......."dreaming", maybe......and then your pressure started chasing the FLs and you had a "runaway".


Den

whatever reason ... That is exactly what I am trying to find out ... why is the FL graph like that? What causes FL to increase?
BTW, I tape my mouth to prevent mouth leak ... could this have anything to do w/ FL increase? I didn't think so ...

Thx.

Without being wired up to a sleep lab diagnostics machine, it's hard to determine what happened. But, like I said, it could be you entered a deep sleep or REM stage and your breathing changed......notice what happened to your respiratory rate at the same time. The machine algorithm "interpreted" the flow limitations and all the rest as impending apneas. That's how they're programmed. But, it isn't always reality as there are so many variations in peoples' breathing.
Personally, when using a range of pressures, I've had practically NONE of the "predictors" occur that the manufacturers program into the machines. And, when I DID have an apnea here or there, virtually none of those "predictors" preceded my apneas. Consequently, I decided I didn't want my sleep disturbed by pressure bumps or (at worst) the type of scenario you're seeing in your own reports. It took me about a week of an Auto pressure range to see my breathing patterns and to determine that changing pressures disturbed my sleep.....big time. So, I've used straight pressure (except for a few occasional naps) ever since (mid-2006).


Den

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Flow limitations can usually be minimized with a small increase in minimum pressure. This can result in less fluctuation in pressure and better sleep. Also, considering how high your pressure is going with very few events, I would limit the top pressure to 16 for now. If additional OA events slip through, you can add more maximum pressure, but my thought is the peak pressure is probably more disruptive than events it "might" be preventing.

I had another possibility come to mind......positional sleep.......wasn't enough to develop into an apnea or shut off your air but caused you to breath heavily and produced flow limitations. I still think "dreaming" may be more plausible though.


Den

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Wulfman... wrote: pressure started chasing the FLs and you had a "runaway".