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

[Sludge]

The new analysis was more than simply waveform shape analysis:

1) as flattening severity increases (e.g., the shape index decreases) the FFL measure increases, 2) where flattening is occurring and ventilation is decreasing, the FFL measure is even more severe, and 3) where ventilation is high (e.g., recovery (big) breaths etc. are occurring) the response to flattening shape index is tempered.

[Sludge]

So with the above in mind, in re:

Sludge who knows what he's talking about says you should try to keep FL under .4.

Sludge did not say exactly that. Rather, he said:

I also don't remember if Sludge said 0.4...but if he did say that...I would probably still primarily look at 95%. If it was below 0.4 or close then the "or below" part of the definition would mean that most of the time things were probably within acceptable limits.

Well, he did say that:

flow limitation is significant ("IMHO" >0.4 in ResMed is significant)

This value was not (at least initially) pulled out of the air. The Rapoport '739 Patent said:

If the flow limitation parameter is between 1 and a predetermined normal reference value, e.g., 0.65-0.8, then the breath is classified as "normal." If the flow limitation parameter is between 0 and a predetermined flow limited reference value, e.g., 0.4, then the breath is classified as "flow limited." If the flow limitation parameter is between the normal and flow limited reference values, then the breath is classified as "intermediate."

This implied that FL less than 0.4 would be attacked.

ResScan would later reverse the reference range (now making 0.6 a potential pivot point), but I just stayed with 0.4, it seemed a good spot to identify "significant".

When the top max number on the graph is 0.5...things are going to look worse than if the top max number is 1.0.

That is basically the point of putting top value at 0.5 (or 0.4). "Significant" becomes more clearly defined.

That said. (and also "IMHO"), this analysis cannot necessarily be extended to the 95% value. What you're really looking for are those FLs that cause problems (RERAs), and that may not be accomplished by trying to boil down FL to 95% <0.4 (AAMOF("IMHO") if you're 95% 0.39, you're a train wreck).

Using 0.4 as the high limit permits better analysis of the FL (or "FFL", as it were).

IOWs, it's not that < 0.4 is good, it's that > 0.4 is bad, and at that point exactly how bad is academic.

[Wulfman...]

So with the above in mind, in re:

Sludge who knows what he's talking about says you should try to keep FL under .4.

Sludge did not say exactly that. Rather, he said:

I also don't remember if Sludge said 0.4...but if he did say that...I would probably still primarily look at 95%. If it was below 0.4 or close then the "or below" part of the definition would mean that most of the time things were probably within acceptable limits.

Well, he did say that:

flow limitation is significant ("IMHO" >0.4 in ResMed is significant)

This value was not (at least initially) pulled out of the air. The Rapoport '739 Patent said:

If the flow limitation parameter is between 1 and a predetermined normal reference value, e.g., 0.65-0.8, then the breath is classified as "normal." If the flow limitation parameter is between 0 and a predetermined flow limited reference value, e.g., 0.4, then the breath is classified as "flow limited." If the flow limitation parameter is between the normal and flow limited reference values, then the breath is classified as "intermediate."

This implied that FL less than 0.4 would be attacked.

ResScan would later reverse the reference range (now making 0.6 a potential pivot point), but I just stayed with 0.4, it seemed a good spot to identify "significant".

When the top max number on the graph is 0.5...things are going to look worse than if the top max number is 1.0.

That is basically the point of putting top value at 0.5 (or 0.4). "Significant" becomes more clearly defined.

That said. (and also "IMHO"), this analysis cannot necessarily be extended to the 95% value. What you're really looking for are those FLs that cause problems (RERAs), and that may not be accomplished by trying to boil down FL to 95% <0.4 (AAMOF("IMHO") if you're 95% 0.39, you're a train wreck).

Using 0.4 as the high limit permits better analysis of the FL (or "FFL", as it were).

IOWs, it's not that < 0.4 is good, it's that > 0.4 is bad, and at that point exactly how bad is academic.

Thanks for the additional information and documentation. I'm not sure how much it cleared up......it may fall into the category of "be careful what you ask for"......but I REALLY appreciate your knowledge and time spent trying to educate us.


Den

.

[Sludge]

So I guess applying Flow Limitation Values to Waveform Analysis would be a little "Over The Top" then?

[Sludge]

Oh well----- I guess I don't have enough posts left to run that discussion very long anyway...

[Sludge]

...back to cleaning out the Nano...

[Sludge]

...boy, I tell ya--

that Rubber Soul is just a great album...

[Sludge]

...after seeing that first Oregon drive, and if somebody told me Ohio State was going to have 4 turnovers, that the Ducks were going to get blown out, I would've said they were crazy...

[tan]

So I guess applying Flow Limitation Values to Waveform Analysis would be a little "Over The Top" then?

By all means, sir

[Sludge]

So I guess applying Flow Limitation Values to Waveform Analysis would be a little "Over The Top" then?

By all means, sir

So instead, as the specter of chiliaphobia raises its ugly head, I'll leave you with

A blonde is watching the news with her husband when the newscaster says "Two Brazilian men die in a skydiving accident."

The blonde starts crying to her husband, sobbing "That's horrible!!! So many men dying that way!"

Confused, he says, "Yes dear, it is sad, but they were skydiving, and there is always that risk involved."

After a few minutes, the blonde, still sobbing, says, "How many is a Brazilian?"

Cya.

[tan]

So I guess applying Flow Limitation Values to Waveform Analysis would be a little "Over The Top" then?

By all means, sir

So instead, as the specter of chiliaphobia raises its ugly head, I'll leave you with

A blonde is watching the news with her husband when the newscaster says "Two Brazilian men die in a skydiving accident."

The blonde starts crying to her husband, sobbing "That's horrible!!! So many men dying that way!"

Confused, he says, "Yes dear, it is sad, but they were skydiving, and there is always that risk involved."

After a few minutes, the blonde, still sobbing, says, "How many is a Brazilian?"

Cya.

Hehe, having bad nights lately? I bet your FLs are off chart.

[palerider]

Cya.

does sludge get washed away when he turns 1000?

[cathyf]

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...

[Wulfman...]

Cya.

does sludge get washed away when he turns 1000?

Yep. AFAIK, none of his previous identities have over 1000 posts (well, maybe one does).
I guess he decided that is his time to switch.
We'll just have to wait and see what the next one will be.


Den

.

[Krelvin]

I think a better statement would be that not all people react the same way. What works good for some, many not work for others. I use an auto range and it works out pretty good. I have few problems sleeping and those problems I do have, many times have nothing to do with the machine, mask, Pressure settings but rather other non-related issues.

The goal for me is not 0 AHI... because that is not realistic "for me"...

When I get up in the morning, the first thing I think about is how I feel. If I feel rested and ready to go, it really don't matter what the AHI was that night. I sometime think that I had an interrupted night and find I actually show a better AHI than I thought it would be... but how I feel is more important.

If things change, and they do, I reevaluate the feedback that I get, my environment and the equipment and try to find out what changed and how to fix it.