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Jay Aitchsee wrote:You folks may enjoy this paper, "The Role of Flow Limitations as an Important Diagnostic Tool..." , http://www.sciencedirect.com/science/ar ... 6315000516
My take on your argument over semantics and definition is that Flow Limitations are a specific type of flow reduction as are apneas, snores, and hypopneas.

Thanks for putting this up, you can have a flow limit without a snore, hypopnea or obstructive apnea, but you can't have a snore, hypopnea or obstructive apnea without a flow limit.
This 30 second section of video also shows the increasing constriction causing a flow limit from 0 -100% of the airway
https://youtu.be/-gie2dhqP2c?t=62

ajack wrote:

Jay Aitchsee wrote:You folks may enjoy this paper, "The Role of Flow Limitations as an Important Diagnostic Tool..." , http://www.sciencedirect.com/science/ar ... 6315000516
My take on your argument over semantics and definition is that Flow Limitations are a specific type of flow reduction as are apneas, snores, and hypopneas.

Thanks for putting this up, you can have a flow limit without a snore, hypopnea or obstructive apnea, but you can't have a snore, hypopnea or obstructive apnea without a flow limit.
This 30 second section of video also shows the increasing constriction causing a flow limit from 0 -100% of the airway
https://youtu.be/-gie2dhqP2c?t=62

only if one makes the *ASSumption" that those are cumulative... which they're not.

Jay Aitchsee wrote:BTW, I think the Dr you couldn't remember the name of is Dr Steven Park, sypark, http://doctorstevenpark.com/

I am now thinking it is Dr David M. Rapoport

I will research the writings of both & see if I can find where 1 of them pushed using BiPap to reduce Flow Limitations (even in a rather lengthy thread on this forum).

ajack wrote:it was your video showing the flow limitation/narrowing of the airway stages leading to apnea, a total blockage. timeframe 1:12 to 1:30 ..Now YOUR video isn't good enough? sure, whatever, an apnea isn't a flow limitation either

That video is entitled "Sleep Disordered Breathing" & discusses all of those items.

But, nowhere does it say that FLs must lead to something else.

Just because I wash my hands in my bathroom does not mean I had to take a s__t first.

StuUnderPressure wrote:

ajack wrote:it was your video showing the flow limitation/narrowing of the airway stages leading to apnea, a total blockage. timeframe 1:12 to 1:30 ..Now YOUR video isn't good enough? sure, whatever, an apnea isn't a flow limitation either

That video is entitled "Sleep Disordered Breathing" & discusses all of those items.

But, nowhere does it say that FLs must lead to something else.

Just because I wash my hands in my bathroom does not mean I had to take a s__t first.

ajack seems to be that in that regrettable class, the "know it all newbie", just got a machine read a little stuff, but has little depth of understanding and is all gung ho to tell everybody how everything is.

You are going to feel very silly when the penny drops. Notice that other long timers aren't backing you?
An obstructive apnea is an above 90% flow limit for 10 seconds or more. You can't have an OA without a flow limit, it's it definition. It obviously doesn't stop being a flow limit, when the event is called an OA

ajack wrote:You are going to feel very silly when the penny drops. Notice that other long timers aren't backing you?
An obstructive apnea is an above 90% flow limit for 10 seconds or more. You can't have an OA without a flow limit, it's it definition. It obviously doesn't stop being a flow limit, when the event is called an OA

again, I'm done, really done this time... you're too thick to understand the difference in a "flow limitation", which is a separately defined thing, and a generic limitation of flow.

you give newbies a bad name, ajack, :sigh:

ajack wrote:You are going to feel very silly when the penny drops. Notice that other long timers aren't backing you?
An obstructive apnea is an above 90% flow limit for 10 seconds or more. You can't have an OA without a flow limit, it's it definition. It obviously doesn't stop being a flow limit, when the event is called an OA

AJack, I agree with PR that Flow Limitations as a metric are distinct from hypopneas and apneas. I will try to explain why when I have a little more time. In the meantime, here's the AASM scoring rules: https://go.aastweb.org/Resources/journa ... events.pdf

that isn't pr claim. PR is saying that they aren't a flow limit.
one type hypopnea definition is a flow limit of more than 30%
I was using
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3459210/
Rules for Scoring Respiratory Events in Sleep: Update of the 2007 AASM Manual for the Scoring of Sleep and Associated Events

ajack wrote:that isn't pr claim. PR is saying that they aren't a flow limit.

as with so many other things, you've got that wrong too.

Jay Aitchsee wrote:

ajack wrote:You are going to feel very silly when the penny drops. Notice that other long timers aren't backing you?
An obstructive apnea is an above 90% flow limit for 10 seconds or more. You can't have an OA without a flow limit, it's it definition. It obviously doesn't stop being a flow limit, when the event is called an OA

AJack, I agree with PR that Flow Limitations as a metric are distinct from hypopneas and apneas. I will try to explain why when I have a little more time. In the meantime, here's the AASM scoring rules: https://go.aastweb.org/Resources/journa ... events.pdf

ajack wrote:that isn't pr claim. PR is saying that they aren't a flow limit.
one type hypopnea definition is a flow limit of more than 30% [emphasis added]
I was using
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3459210/
Rules for Scoring Respiratory Events in Sleep: Update of the 2007 AASM Manual for the Scoring of Sleep and Associated Events

Very quickly:
No, the rule states (in part):

(If) The peak signal excursions drop by ≥ 30% of pre-event baseline using nasal pressure (diagnostic study), PAP device flow (titration study), or an alternative hypopnea sensor.

It does not mention Flow Limitations or flow limit.

Your argument has been about semantics, definitions, and usage of terms.
ResMed scores machine detected Flow Limitations based on the degree of flattening of the inspiratory Flow Wave. The AASM does not score Flow Limitations by the degree of flattening, but does state:

Flattening of the inspiratory portion of the flow waveform provides evidence of airflow limitation and increased upper airway resistance.

But, AASM scored hypopneas may, or may not, exhibit "flattening of the inspiratory portion of the nasal pressure (or PAP device flow) waveform".

BTW, here's a snip containing an obstructive apnea. Notice there is no Flow Limitation scored (there is one of 0.07 starting at 01:59:30).

Does the ResMed AirSense 10 AutoSet or the ResMed AirSense AutoSet for Her treat Flow Limitations any better than the ResMed S9 AutoSet?

StuUnderPressure wrote:Does the ResMed AirSense 10 AutoSet or the ResMed AirSense AutoSet for Her treat Flow Limitations any better than the ResMed S9 AutoSet?

they all raise pressure, that's the only way to 'treat' flow limitations.

StuUnderPressure wrote:Does the ResMed AirSense 10 AutoSet or the ResMed AirSense AutoSet for Her treat Flow Limitations any better than the ResMed S9 AutoSet?

The for her special mode will flag more FLs...make it look a lot more active than the regular mode (I had one person be a guinea pig and do both modes so I could see the FL graphs).

The for Her mode isn't as aggressive in terms of pressure response as the regular mode. Remember it's designed to be "gentler/kinder" for sensitive people.
It's slower to respond and you still have to have the minimum pressure up there as a starting point.

"Better" would only apply if you were extremely sensitive to even the slightest pressure change and needed a kinder/gentler response.

Only way to know for sure how it might work with you in your situation...get one and check it out.

Here is my situation & why this has come up all of a sudden.

Sleep Doctor wants to do another Sleep Study including a BiPap Titration. (See why at the end of this post.)
If I qualify, she would write me an Rx for the ResMed Air Curve 10 ASV.

If I do not qualify, I get nothing new because I am not due for another machine for a couple of years.
So, I would have to keep using my ResMed S9 AutoSet.

Basically, I do not want to go through another Sleep Study unless:
I am pretty sure I would qualify for the Air Curve 10 ASV
AND
Using the Air Curve 10 ASV would reduce my current high Flow Limitations

Since it appears there is a good chance that neither may occur, I am pretty sure I will not agree to another Sleep Study.

However, I do reserve the right to change my mind if I can find more credible evidence that using the ResMed Air Curve 10 ASV would reduce my current high Flow Limitations.

Now, here is why the Sleep Doctor suggested the new Sleep Study (besides the additional income it would bring to the facility):

For quite a while, my pressure was getting to 20 on most nights on the ResMed S9 AutoSet.
Hence the Sleep Doctor talk of going to a BiPap for the higher pressure it could go up to.

Sleep Doctor knows even less about Flow Limitations than XXX who posted in this thread - so I have never really discussed that with her.
Convincing her that I need the ResMed Air Curve 10 ASV to reduce my Flow Limitations would be futile.

After switching to EPR 3 on the ResMed S9 AutoSet only about 1 1/2 weeks ago, my pressure usually averages 13 - 14 (with a range of 13 - 16).
AND my Flow Limitations are now lower - but still not low enough.

Yep, the reason why for either is a mystery to me also.

That is what started my quest (or maybe it is only a pipe dream!) - that the additional settings available on the ResMed Air Curve 10 ASV would allow me to lower my Flow Limitations even more than what just turning on the EPR 3 on the ResMed S9 accomplished.

Sorry I took up so much of your time.
Now you can get back to more serious business.