Can Someone Explain How This Is An Obstructive Event

[SleepyEv]

So I was just diagnosed with OSA, but am not 100% convinced it's actually obstructive in nature. I have a fairly low AHI (5-10) and almost all are Hypopneas, but it's very crippling as I'm always awakening. Can't get more than a 1 hour stretch in. In any case, I was looking at Sleephead data, and while it's obvious there is something going on due to the dips in minute vent and the jagged flow, I can't understand how it's an obstructive event without a flattening of the flow rate. Being that it was labeled a 71 second event, this is a snapshot of roughly the entire event. Does this make any sense? Any idea what else it could be?

[Sleeprider]

This event starts off with a flow limitation with snore (see downward sloping inspiration with jagged top) at 05:32:55. It proceeds with diminishing respiratory volume, all showing flow limits until there is a recovery breath at 05:33:45, followed by a ragged looking expiration and second recovery breath. Flow then gradually diminishes again with flow limitation suggested by flat-topped inspriatory flow, and an OA that tanks the tidal volume. The end of the segment does not show a recover breath but continued low flow.

I think you need higher minimum pressure as your pressure is 5.0/4.2 through the entire sequence. This is just too low to stabilize your breathing, and I think you woul notice a lot of difference at a pressure of 6.5 or 7.0.

[SleepyEv]

Wow, thank you Sleeprider - you know your charts! I do know that the pressure is way low I am trying desperately to get used to the machine and set it on its lowest setting to try and get some data on it while I get used to it but 6-7 is definitely doable. So this CAN be an obstructive event - I've always thought that it had to flatline (to a certain degree)....interesting.

[dmeRT]

if the waveform diminishes by 30% it's considered a hypopnea. if it diminishes 70%(could be 90% - i forget) it's scored as an obstructive apnea. Both fall under the obstructive in nature apneas. Also, the decrease in flow(event) has to last at least 10 seconds.

[trish6hundred]

Hi SleepyEv,
WELCOME! to the forum.!
Hang in there for more responses to your post, good luck with CPAP therapy.