New machine + new mask = WORSE results?

Pugsy · Post by **Pugsy** » Sat Jun 13, 2026 2:32 pm

Amishboy51 wrote: ↑
Sat Jun 13, 2026 1:39 pm
That AHI indicates that I'm receiving effective therapy. I definitely found THAT comforting!]

Well that's all well and good if nothing happens when those really big leaks happen but you do understand that when leaks are over the 30 to 35 L/min range that the machine could lose the ability to sense, record and/or respond to anything that might happen and you can't trust a nice low AHI to mean that nothing happened. With a large amount of time spent over 35 L/min and you don't have events you don't know for sure if nothing happened or if the machine was clueless during those big leak times and when you spend a lot of time in really big leak territory you can't trust the AHI to be accurate.

Now short amounts of time probably not a big deal but some of yours is a LOT of time deep into large leak territory and the lack of events during those really big leaks could possibly be masking those events. Just because you slept through them and they don't bug you doesn't mean you also didn't sleep through a truck load of apnea events that the machine didn't know happened so it could record them due to big prolonged leaks.

So your AHI during times deep into large leak territory could potentially be suspect. Not saying it is suspect but it could be.

My leak graphs are rarely without some leak and sometimes it is quite large but never very long in duration so I don't worry so much about them because I also sleep through them and they don't bug me. Leaks like yours I would worry about though.

Nocibur · Post by **Nocibur** » Sun Jun 14, 2026 2:59 am

Another night of data is June 9th where there is more interesting discussion material:

: boy1.jpg (59.24 KiB) Viewed 294 times

There is obvious FL but no machine response.

Is the FL value assigned too low to consider pressure increase?

Is this the old "A10 Algorithm" where ResMed machines do not respond to FLs?

Are the SleepHQ parameters listed wrong (the mask info appears wrong. IIRC pressure values aren't updated automatically either)?

More inappropriate pressure behaviour without massive leaks (maybe some spot LL):

: boy2.jpg (61.6 KiB) Viewed 294 times

Consider EPR.

Anyway you kids got your work cut out for you!

Nocibur · Post by **Nocibur** » Sun Jun 14, 2026 4:23 am

Course you could always go to Plan B: Fixed Pressure.

Jason will love you!

Amishboy51 · Post by **Amishboy51** » Sun Jun 14, 2026 4:29 pm

Nocibur wrote: ↑
Sat Jun 13, 2026 1:16 pm

Amishboy51 wrote: ↑
Sun May 24, 2026 2:25 pm

Am I crazy to think that my therapy has deteriorated since making these changes?
The massive leaks have destroyed everything. Your breathing, the ability of the machine to record events, the ability of the machine to address events (pressure is actually dropping during wicked events):

boy.jpg

All I can see is June 9. Try to upload some "good" March stuff.

You need an oximeter.

Not that other guy.

Thanks, let me try to respond to some of your points.

First, I've been trying to use a free SleepHQ account only since late May (although it's been a continuous struggle to upload files and get any reports), so I don't have anything from March (aside from OSCAR results). I'll attach another link to my SleepHQ files. https://sleephq.com/public/teams/share_ ... 2ed84f79a1

Second, what would an oximeter do?

Third, who is "that other guy"?

Amishboy51 · Post by **Amishboy51** » Sun Jun 14, 2026 4:37 pm

Nocibur wrote: ↑
Sun Jun 14, 2026 2:59 am
Another night of data is June 9th where there is more interesting discussion material:

boy1.jpg

There is obvious FL but no machine response.

Is the FL value assigned too low to consider pressure increase?

Is this the old "A10 Algorithm" where ResMed machines do not respond to FLs?

Are the SleepHQ parameters listed wrong (the mask info appears wrong. IIRC pressure values aren't updated automatically either)?

More inappropriate pressure behaviour without massive leaks (maybe some spot LL):

boy2.jpg

Consider EPR.

Anyway you kids got your work cut out for you!

Sorry, I appreciate your efforts to explain this to me, but aside from stating that the mask info (AirTouch N20) is correct, I can't provide any answers; your questions are simply way over my head. I don't understand FL (assuming that's Flow Limit), A10 Algorithm, SleepHQ parameters, etc.

Amishboy51 · Post by **Amishboy51** » Sun Jun 14, 2026 4:47 pm

Pugsy wrote: ↑
Sat Jun 13, 2026 2:32 pm

Amishboy51 wrote: ↑
Sat Jun 13, 2026 1:39 pm
That AHI indicates that I'm receiving effective therapy. I definitely found THAT comforting!]
Well that's all well and good if nothing happens when those really big leaks happen but you do understand that when leaks are over the 30 to 35 L/min range that the machine could lose the ability to sense, record and/or respond to anything that might happen and you can't trust a nice low AHI to mean that nothing happened. With a large amount of time spent over 35 L/min and you don't have events you don't know for sure if nothing happened or if the machine was clueless during those big leak times and when you spend a lot of time in really big leak territory you can't trust the AHI to be accurate.

Now short amounts of time probably not a big deal but some of yours is a LOT of time deep into large leak territory and the lack of events during those really big leaks could possibly be masking those events. Just because you slept through them and they don't bug you doesn't mean you also didn't sleep through a truck load of apnea events that the machine didn't know happened so it could record them due to big prolonged leaks.

So your AHI during times deep into large leak territory could potentially be suspect. Not saying it is suspect but it could be.

My leak graphs are rarely without some leak and sometimes it is quite large but never very long in duration so I don't worry so much about them because I also sleep through them and they don't bug me. Leaks like yours I would worry about though.

Thanks, again, Pugsy.

So, in short, I DO need to be concerned about the leaks, despite the controlled AHI? And I can't just disregard the abysmal myAir scores (usually anywhere from 0-5 out of 20)?

Then I'm back to my original quandary: how exactly do I go about improving the mask fit?! I've watched dozens of videos on YouTube (from ResMed as well as DME providers, etc.), and pretty much all I learn is "don't over-tighten the mask." And I don't think my local DME or pulmonologist has any greater "expertise."

Nocibur · Post by **Nocibur** » Mon Jun 15, 2026 3:11 am

Amishboy51 wrote: ↑
Sun May 24, 2026 2:25 pm
... the technician ... immediately said that I was doing a lot of breath breathing, so he recommended that I switch from my Resmed N20 nasal mask to a facial mask...

On about March 27th, I finally changed from the Resmed N20 mask and cushion to an F30i.

Amishboy51 wrote: ↑
Sun Jun 14, 2026 4:37 pm
... the mask info (AirTouch N20) is correct...

Well then the problem is breath breathing.

Nocibur · Post by **Nocibur** » Mon Jun 15, 2026 3:13 am

Are you pulling the SD card out of the machine as soon as you turn it off?

Nocibur · Post by **Nocibur** » Mon Jun 15, 2026 3:28 am

Amishboy51 wrote: ↑
Sun Jun 14, 2026 4:29 pm
...what would an oximeter do?

Well, now this is only my opinion, but everything you've done up to this time has been a complete waste of time.

"IMO" you have near complete fixed nasal obstruction (which means that conceivably you don't even have "obstructive" sleep apnea).

You need to go all the way back to Square1. Get all the original diagnostic data you have.

Nocibur · Post by **Nocibur** » Mon Jun 15, 2026 3:44 am

Nocibur wrote: ↑
Mon Jun 15, 2026 3:28 am
... you don't even have "obstructive" sleep apnea...

At least in the traditional sense...

Amishboy51 · Post by **Amishboy51** » Mon Jun 15, 2026 8:13 am

Nocibur wrote: ↑
Mon Jun 15, 2026 3:13 am
Are you pulling the SD card out of the machine as soon as you turn it off?

Yes, usually within a few minutes.

Amishboy51 · Post by **Amishboy51** » Mon Jun 15, 2026 8:18 am

Nocibur wrote: ↑
Mon Jun 15, 2026 3:28 am

Amishboy51 wrote: ↑
Sun Jun 14, 2026 4:29 pm
...what would an oximeter do?
Well, now this is only my opinion, but everything you've done up to this time has been a complete waste of time.

"IMO" you have near complete fixed nasal obstruction (which means that conceivably you don't even have "obstructive" sleep apnea).

You need to go all the way back to Square1. Get all the original diagnostic data you have.

Interesting, but, unfortunately, I don’t think I have any of that (or even know where to look); the original diagnostic data might’ve been almost 30 years, 3 moves, and multiple doctors ago.

Amishboy51 · Post by **Amishboy51** » Mon Jun 15, 2026 8:22 am

Amishboy51 wrote: ↑
Sun Jun 14, 2026 4:47 pm

Pugsy wrote: ↑
Sat Jun 13, 2026 2:32 pm

Amishboy51 wrote: ↑
Sat Jun 13, 2026 1:39 pm
That AHI indicates that I'm receiving effective therapy. I definitely found THAT comforting!]
Well that's all well and good if nothing happens when those really big leaks happen but you do understand that when leaks are over the 30 to 35 L/min range that the machine could lose the ability to sense, record and/or respond to anything that might happen and you can't trust a nice low AHI to mean that nothing happened. With a large amount of time spent over 35 L/min and you don't have events you don't know for sure if nothing happened or if the machine was clueless during those big leak times and when you spend a lot of time in really big leak territory you can't trust the AHI to be accurate.

Now short amounts of time probably not a big deal but some of yours is a LOT of time deep into large leak territory and the lack of events during those really big leaks could possibly be masking those events. Just because you slept through them and they don't bug you doesn't mean you also didn't sleep through a truck load of apnea events that the machine didn't know happened so it could record them due to big prolonged leaks.

So your AHI during times deep into large leak territory could potentially be suspect. Not saying it is suspect but it could be.

My leak graphs are rarely without some leak and sometimes it is quite large but never very long in duration so I don't worry so much about them because I also sleep through them and they don't bug me. Leaks like yours I would worry about though.
Thanks, again, Pugsy.

So, in short, I DO need to be concerned about the leaks, despite the controlled AHI? And I can't just disregard the abysmal myAir scores (usually anywhere from 0-5 out of 20)?

Then I'm back to my original quandary: how exactly do I go about improving the mask fit?! I've watched dozens of videos on YouTube (from ResMed as well as DME providers, etc.), and pretty much all I learn is "don't over-tighten the mask." And I don't think my local DME or pulmonologist has any greater "expertise."

And, just to be absolutely clear, are you also saying my AHI data might be inaccurate, because of the lengthy, large leaks?!

Pugsy · Post by **Pugsy** » Mon Jun 15, 2026 8:46 am

Amishboy51 wrote: ↑
Mon Jun 15, 2026 8:22 am
just to be absolutely clear, are you also saying my AHI data might be inaccurate, because of the lengthy, large leaks?!

Yes.
It MIGHT be inaccurate. I can't say for sure but there is a reason that there is something called large leak territory that causes the machine to measure leaks. If it wasn't important I would think that they wouldn't bother measuring leaks.
ResMed uses the 24 L/min excess leak threshold....remember ResMed removes the intentional leak (normal venting rate) before it reports leaks. So you get excess leak only from a ResMed machine. I think that is an ultra conservative number but from my own personal experience it isn't until we hit 30-35 L/min that the machine might miss something. Not a given for sure thing but there is a definite "might" or "maybe" going on there.

It might also be that your reported AHI is for sure nice a low and accurate but the problem is that "might be inaccurate" and you can't prove otherwise when there's that much large leak going on.

I don't know about you but I am not in love with cpap myself and if I am going to have to use this stuff I damn well want the peace of mind that my data is accurate. I don't want to poo poo off a half the night deep into large leak territory reported AHI just because it is nice and low.

Nocibur · Post by **Nocibur** » Mon Jun 15, 2026 10:30 am

Pugsy wrote: ↑
Mon Jun 15, 2026 8:46 am
I think that is an ultra conservative number but from my own personal experience it isn't until we hit 30-35 L/min that the machine might miss something. Not a given for sure thing but there is a definite "might" or "maybe" going on there.

If we believe the patent the bottom drops out at 42 LPM leak:

For similar reasons, the procedure “calculate flow limitation threshold” sets the flow limitation threshold to a lower value corresponding to more severe flow limitation, if the pressure is already high or if there is a large leak:

IF mask leak is greater than 0.7 L/sec set leak roll-off to 0.0

ELSE if mask leak is less than 0.3 L/sec set leak roll-off to 1.0

ELSE set leak roll-off to (0.7-mask leak)/0.4

END

Set pressure roll-off to (20-mask pressure)/16

Set flow limitation threshold to 0.15 times pressure roll-off times leak roll-off

New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Re: New machine + new mask = WORSE results?

Machine	Mask

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Additional Comments: ResMed AirTouch F30i

Machine	Mask

Additional Comments: ResMed AirTouch F30i

Machine	Mask

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