What does this tell me Sleepyhead

[TASmart]

TBMx: Thanks for taking the time to give the detailed logic behind your thinking. I do have a very technical background and see where you are coming from here. I think I can summarize your thinking here, that the data as to AHI is unreliable because of the inherent errors in measuring the flows and pressures. Is that correct?

If so, then to some degree I have an issue with that, because the autoset process with all its true and implied leaks still works for a large population. So is the analysis so overly esoteric that in the actual work of apnea sufferers it really does not matter? Are you claiming that the AHI are not accurate enough to make parameter adjustments in my case?

Lets try to round this back to the general user level as to what to do with this type of data.

Thanks!

[TBMx]

to be honest what troubled me most was you 'saying' (I'm exaggerating here - so please don't take this as an offense):
"the events and therefore the AHI is right ... I don't care for the leakrate as this value has an error"
sth like that I really can't take ... either all is crap or all has (to some degree) quality ... but picking out sth and saying "that's true" and everything else is "just measurement error and therefore of no concern" makes no sense at all! (at least to me)


I would change the mask-setting to pillows first and than take a look.

just from that "data" you seem to have a RERA or Hypopnea "problem" ... raising the pressure will most likely work (basically you than have the same as CPAP ... and if really further obstructions arise there is room for the machine)
(I do not beleive your centrals are a problem ... most likely (can't say that without looking at the detailed data) you simply reduced your breath after the hypopnea/RERA recovery breaths ... most likely there was still "microflow" (around or below 25% of normal flow) ... if they don't vanish if the hypopneas are gone you can still care about them^^)

but in the end your machine now indicates a lot of "clear airway"-like hypopneas (as the machine didn't raise the pressure because it detected no flowlimitation) - you obviously didn't have that before - centrals do not vanish if you raise the pressure - obstructive ones do ... all there is to take away is "the data is crap! - fix that"
(sorry ... but there is really no way I can talk sense into that data and with what you said you had with CPAP 11 ... it simply makes no sense at all - at least to me ... maybe someone else really can make sense out of that)

But I'm not convinced from that data that you really have more hypopneas ... they might be 'just' RERAs (if so - I would advise to try out the autoset for her modus as it responds to RERAs (the most) and creates a more "evenly" pressure)

.. but I'm not the right address to ask for changes in settings - I can understand the raw-data (to some degree) at a low-level-scope ... nothing more^^ ... ask me if you want to know if you should put trust in certain events ... bigger picture or treatment is not really my domain.
(I have an AHI below 1 with my settings and if I take the time and look on my data and my AHI is even slightly above 1, I have a very close eye-to-eye discussion with my machine about each hypopnea and apnea about whose fault that was^^ (really! - last time that happened 'we' came to the conclusion that I simply forgot to change the HEPA-filters (the very fine-filters) - (after over half an hour o.O ... my machine was really insisting it did nothing wrong)^^)

[OpalRose]

Lets try to round this back to the general user level as to what to do with this type of data.
Thanks!

TASmart, I agree with you.

TBMx, thanks for your insight and knowledge, but I feel this thread is getting a little confrontational.
We are here to help and guide one another.

[eseedhouse]

 with APAP there is only 1 acceptable leakrate and that is 0.0!)

Wrong.

First, there must be a leak in the mask or you would stop breathing due to excessive CO2. 

Some machines report all leaks, including the intentional ones.  For those machines a reported leak rate of 0 would be extremely concerning!  Others only report leaks above the intentional leak and for them 0 is ideal, but a small amount is not really worrying. 

The search for unattainable perfection is often the enemy of "good enough".  Trying to get that leak rate down to 0 might cause discomfort and poor sleep, and a small leak would be better than that.

[TBMx]

@eseedhouse: you are absolutely right! in many cases trying to achieve a better AHI (or aiming for 0.0) does not make any thing better - sometimes worse.

We were talking about a Resemd Airsense 10 - there is no total-leak shown to the user - just plain leak! (I believe you call what I call leak "exzessive ~" or "unintentional leak" - CO2-Vent-Flow is no real "leak" for me in that matter as it is essential and fixed, pressure dependent)

But nevertheless ... leaks do affect event-detection ... sometimes the machines get the leakrate right - sometimes (as in this case) it is "confused" and therefore every data after that is wrong^^ (total different views on total different things - I am talking about the ability to detect events ... that is not the same as getting a good treatment)

[eseedhouse]

"We were talking about a Resemd Airsense 10 - there is no total-leak shown to the user - just plain leak! (I believe you call what I call leak "exzessive ~" or "unintentional leak" - CO2-Vent-Flow is no real "leak" for me in that matter as it is essential and fixed, pressure dependent)"

Well no.  The Airsense 10 reports total leak including the built in intentional leak.  At least that's what my Airsense 10 reports vial SleepyHead.

"But nevertheless ... leaks do affect event-detection ... sometimes the machines get the leakrate right - sometimes (as in this case) it is "confused" and therefore every data after that is wrong^^ (total different views on total different things - I am talking about the ability to detect events ... that is not the same as getting a good treatment)"

When leak is too high the AHI reported by the machine may be inaccurate, but the leak rate will be reported accurately.  At least that's the way I understand it.

[TASmart]

This is interesting. I had always been lead to believe the leaks reported had the leak rate of the mask vent subtracted off. But the Resmed interpretation guide says this:

[TBMx]

I do not mean to offend ... most of my texts are self-therapeutic^^

whether or not the CO2-Vent-Flow ist included in the "leak-rate" is easily checked if you look up the Flow-pressure-curve in the manual of your mask.

The minimal necessary "intentional leak" needed to wash out the CO2 can also easily calculated by taking your average tidal volume and multiplying it with your average breaths per minute multiplied by 2.
(the 2 comes from the fact that the CO2 needs to be washed out during the exspiration phase - not exact science - just a rough estimation)

Let's say you have an average tidal volume of 500 ml with 20 breaths per minute = 0,5 * 20 * 2 = 20 liters per minute.
everything below that would cause rebreathing (thus most likely ending in hyperventilation, headaches .... whatever).

[PaytonA]

This is interesting. I had always been lead to believe the leaks reported had the leak rate of the mask vent subtracted off. But the Resmed interpretation guide says this:

This says specifically that Resmed estimates the mouth and mask leaks by analyzing the respiratory flows together with the vent flows not by including them.

Best Regards,

PaytonA

[PaytonA]

Ed,

I may be misunderstanding your post but it is P-R and the other companies machines that report total leaks. Resmed estimates the unintentional leaks only.

Best Regards,

PaytonA