+- Apnea Board Forum - CPAP | Sleep Apnea (https://www.apneaboard.com/forums)
+-- Forum: Public Area (https://www.apneaboard.com/forums/Forum-Public-Area)
+--- Forum: Main Apnea Board Forum (https://www.apneaboard.com/forums/Forum-Main-Apnea-Board-Forum)
+--- Thread: What's happening?? (/Thread-What-s-happening)
Pages:
1
2
RE: What's happening?? - tedgreen - 08-15-2017
If you look at the last graph I posted, Sleepyhead reports no flow limitation whatsoever before and during the first obstructive event.
Surely, an obstructive event should mean a flow limitation closed to 1 (or 100%)???
The second and third OA events (following shortly) only show a flow limitation of up to 0.25, so why are they classified as OA?
Makes no sense to me, and it looks like either a bug in Sleepyhead, or in the raw data generated by the Resmed machine
RE: What's happening?? - Sleeprider - 08-16-2017
Ted, we very commonly see obstructive events arise "out of the blue" with no preceding flow limitation. Individuals that show that pattern require a higher minimum pressure since the machine does not get a warning. Similarly, we see chronic flow limitation with no following events. Those individuals require limits on maximum pressure. You simply cannot generalize the association of FL with OA.
RE: What's happening?? - tedgreen - 08-17-2017
Sorry, I don't get it.
Surely, a serious flow limitation measured by the machine means an obstructive event.
How does my machine determines OA or HA events, apart from measuring flow limitation??
The word "obstructive" should surely indicate a large restriction of respiratory flow.
Therefore, the flow limitation chart should spike or have a vertical line at the same time as an obstructive event. I understand it may be very sudden instead of progressive, but my flow limitation chart does not seem to show any relation to OA events. On the first 2 OA events on the chart below, no flow limitation is measured...
![[Image: mx2wGRZ.png]](https://i.imgur.com/mx2wGRZ.png)
RE: What's happening?? - Walla Walla - 08-17-2017
At any one time the machine can only select one of 5 things. OA, H, CA, FL, or nothing at all. They may be right next to each other but only one can be registered at any given time. Read RobySue's Beginners Guide to SleepyHead in the software support forum. It explains flow limitations well.