Lots of OAs

palerider wrote: ↑

Mon Aug 27, 2018 7:39 pm

*documented*:
OA/hypopnea response: Increases pressure based on current pressure every 10 s of apnea: increment max 3 when pressure is 4. Increment drops linearly down to 0.5 when pressure is 20.

Flow limitation response: S9/Air10
: uses 3 breath average FL index. Increment typically around 0.6/breath for severely flow limited breaths. Lower increment if lower FL index, high leak or as pressure increases further above 15;

Snores: S8–S9: increment max 1/breath. Lower increment if snore is less severe, high leak or as pressure increases further above 10 S10: increment max 0.6/breath for a loud snore otherwise same as S9.

Your mistake is assuming that the response to obstructive apneas is the same as the response to flow limitations and snores.

Too near bedtime to soak this up and respond. But thank you very much for this information!

djams wrote: ↑

Mon Aug 27, 2018 7:47 pm

I've gotta tell you that I've grown to appreciate that fast response - believe it's important for me. I never have it at the beginning of the night since I'm side sleeping now (take a bow, Pugsy). This was when it would wake me up. So I'm all in on it.

And given that BlueDragon's machine was on "Standard' response, I will give "soft" a test just to see how it compares. Someday. I'll have to intentionally sleep supine to give it an honest go.

Don't mind being the oddball outlier at all - kinda the story of my life!

The problem I was discussing was on my wife's machine, which has always been set to "standard" response. I have used "soft" response on my machine for several weeks. I find that the pressure does not go as high (about 2 cm less than with "standard" response) for FL (I only rarely get an OA myself), with improved AHI results.

You might be interested in https://www.ncbi.nlm.nih.gov/pmc/articl ... der-8-425/ for more details on how different machines respond to different events.

palerider wrote: ↑

Mon Aug 27, 2018 7:39 pm

*documented*:
OA/hypopnea response: Increases pressure based on current pressure every 10 s of apnea: increment max 3 when pressure is 4. Increment drops linearly down to 0.5 when pressure is 20.

Flow limitation response: S9/Air10
: uses 3 breath average FL index. Increment typically around 0.6/breath for severely flow limited breaths. Lower increment if lower FL index, high leak or as pressure increases further above 15;

Snores: S8–S9: increment max 1/breath. Lower increment if snore is less severe, high leak or as pressure increases further above 10 S10: increment max 0.6/breath for a loud snore otherwise same as S9.

Was able to do the math on the FL response. Kinda - it isn't exact. I estimated an average of individual FL over the duration of it's upward climb. Just don''t feel like calculating the 3 breath rolling average over 21 breaths tonight. That said, I'm coming within 0.5cm of the actual increase. Counting the number of breaths in the flow chart over the duration of the increase. My conclusion is that the fast pressure increases I see are very possible with the specs stated above. It happens in my case I think because my FL's are.. violent? amazingly awesome? They jump up quick. I'll put a more accurate calculation on my list of thing to do on a rainy day.

Didn't do any calculations on snores/OA's - FL's are always what cause the quick jump for me.

palerider wrote: ↑

Mon Aug 27, 2018 7:39 pm

Your mistake is assuming that the response to obstructive apneas is the same as the response to flow limitations and snores.

I appreciate you pointing this out, and providing the information. The training continues.

BlueDragon wrote: ↑

Mon Aug 27, 2018 8:34 pm

The problem I was discussing was on my wife's machine, which has always been set to "standard" response. I have used "soft" response on my machine for several weeks. I find that the pressure does not go as high (about 2 cm less than with "standard" response) for FL (I only rarely get an OA myself), with improved AHI results.

Interresting - don't believe I'd see the same results due to the nature of my FL's. I'm sure I'll still try "soft" at some point. Right now I'm focused on getting my settings right. Really close, but not ready to diverge from this path yet.

BlueDragon wrote: ↑

Mon Aug 27, 2018 8:34 pm

You might be interested in https://www.ncbi.nlm.nih.gov/pmc/articl ... der-8-425/ for more details on how different machines respond to different events.

You're correct - I'm very interested. Thanks for the link! I'll have a chance to digest that sometime over the weekend.