ResMed users -- what do your flow limitations look like?

cathyf wrote: When I am having FLs, then the ResMed scientists and engineers think that I need a higher pressure. When the FLs drop off, then the ResMed scientists and engineers think that I need a lower pressure. A guy who goes by the handle "Wulfman" on the Internet evidently thinks that the ResMed scientists and engineers are full of crap. I need a better argument than that...

*giggle*

cathyf wrote:

Wulfman... wrote:I've tried to tell you before that with your Flow Limitations, you should not be using a range of pressures.
I suspect that by posting your reports, it's starting to finally sink in?.

No, In fact your position is completely confusing to me. What you seem to be saying is that people who have the sort of apnea that an autopap was designed to treat shouldn't let the autopap treat their apnea. ResMed has spent years and millions of dollars doing research and engineering creating a CPAP machine that reacts to the presence and absence of flow limitations by changing the pressure. When I am having FLs, then the ResMed scientists and engineers think that I need a higher pressure. When the FLs drop off, then the ResMed scientists and engineers think that I need a lower pressure. A guy who goes by the handle "Wulfman" on the Internet evidently thinks that the ResMed scientists and engineers are full of crap. I need a better argument than that...

I've never said they're full of crap! These are very sophisticated machines. They build in lots of parameters and options into these machines. The idea being that some people can use or not use (turn or off) whatever they wish in order to optimize their therapy. An "Auto" in uncontrolled mode (without parameters) doesn't always provide optimal therapy for EVERYBODY. And, after seeing your reports, ranges of pressures are definitely NOT for YOU.

I don't give a crap how many millions these manufacturers have spent on their technology. Ignoring the possibility of tweaking the parameters and settings that have been built into the machines is a recipe for very lousy sleep and therapy.
Far too many people think "WOW, I've got this expensive, whiz-bang "Auto" that is supposed to KNOW what to do and I HAVE to let it do what it wants to do." Nothing could be further from the truth. These things respond to "air flow" (or lack thereof) and the internal programming and sensors. It's a computer and programming built into an air compressor (originally invented as a vacuum cleaner in reverse)......if this condition exists, then do this, else do this (or nothing). SOME people have "air flows" that can really mess up their therapy by letting the machines do "what they want to".

Flow Limitations are one of the things that are detected (in theory that they and Snores are a precursor to apneas) and responded to. Not everyone has Flow Limitations or Snores that lead to apneas. Many of us have "frank" (our of nowhere) apneas without precursors (speaking from my own and others' therapy reports). So, why let a machine run its pressure all over the place chasing things like Flow Limitations and Snores that don't lead to apneas? For many people, the pressure changes disturb their sleep.

You can believe whatever you want. It's YOUR therapy.


Den

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Cathy, I think it is possible that both Flow Limitations and/or APAP could disturb sleep. Pictured above is representative of my flow limitations with and with out a soft neck brace.

This is what I've found: In the Auto mode, my S9 will drive the pressure up in response to FL, neck brace or no, although for any given min-max settings the average pressure over night will be lower when a brace is used.

For me, relatively little pressure is needed to eliminate obstructive apneas, around 7, yet in the auto mode set at 7-10, flow limitations will drive the average pressure up to over 9. The resulting AHI is low, around 1.0, but made up primarily of CA's which I believe are really arousals caused by pressure variations, mask leaks or a combination.

Decreasing the spread, say to 9-10, maintains the AHI, decreasing the CAI slightly, but increases the leak rate.

Now, going to a fixed CPAP of 8 and adding a neck brace slighty lowers the AHI, with AI lower, CAI lower, and HI a little higher.

But the real telling of this story is in the Zeo results.
At 7-10, Zeo reports 4% deep and 7% Wake
At 9-10, Zeo reports 6% deep and 10% Wake
At 8 fixed, Zeo reports 12% deep and 3% Wake, a dramatic improvement.

All the above stats are averages derived from data gathered over several days in each condition. Last night, at 8 fixed with brace, my AHI was 1.28 with an HI of 0.51. Zeo reported 17% deep, 1.4% wake and a total sleep time of 7 hours 40 minutes. And, and I feel pretty darned good. My average sleep time in the past has been less than 6.5 hours.

So, I think in overcoming the Flow Limitations, the S9 auto therapy disturbs my sleep. But by using the neck brace, I can reduce the Flow Limitations (which if unchecked could be disturbing) allowing me to use the less disturbing CPAP mode. In fact, in a discussion of this yesterday, my sleep doctor who had previously recommended the 7-10 auto, suggested I try reducing the pressure from fixed 8 to 7 while using the brace.

If you want to try a neck brace, mine is pretty simple. It's about a 3" x 8" piece of one inch foam wrapped in handkerchief, with a hair band pinned to the front. I slip it over my head so that the foam piece is under my chin. It's a lot more comfortable than the commercial ones since there is no bulk around the sides and back of the neck.