frustrated re: lack of improvement w #'s

[RMinOntario]

I have been very conservative about changing my pressure in the Elite II to help get better data. Originally, I was at a pressure of 12 for 2 weeks, 13 for a week & 14 for most of a week. All the time my EPR was set to 3. Leaks were not great, but reasonable (I think) 1.2l/m - 10l/m.

After a suggestion here on the forum, I turned the EPR off and am now comfortable with that. That way my pressure would not fluctuate. The next 8 nights I had pressure of 12cm. For the 8 nights, my #'s are: AI - 1.4, HI - 7.8, AHI - 9.2, Time in apnea 0.4%, and leaks - 12l/min. Last night I went up to 13cm of pressure & my numbers in all categories were higher: AI - 1.9, HI - 10.0, AHI - 11.9, time in apnea - 0.7 and leaks 15.6l/min.

When I look at the detail charts, a decent part of my nights are showing no leaks at all. I don't wake up much at all except for an occasional bathroom break, so don't notice the leaks to correct them. My apnea & hypopnea events are not happening just when there are leaks, but often when the leak line is flat.

I'm not sure what to do next. My plan is to stay at 13 for 5-7 nights and I suppose go up to 14 again. I don't know what I can do about the leaks, since they are not constant and they don't wake me up.

BTW, I'm using the Activa LT nasal mask and it is only 5 weeks old.

Any ideas would be appreciated.

[bdp522]

It may be that your are mouth breathing/leaking. Remember that your machine takes the vent flow rate into consideration when it shows leaks. So your leaks are actual leaks. Maybe try taping your mouth for a night or two to see what happens.

Brenda

[RMinOntario]

I guess mouth breathing is a possibility. I thought that it would happen throughout the night if I breathed thru my mouth, but it is worth a try. I have had a number of nights with 0 - 1.2l/min leaks, so thought mouth breathing wasn't a problem for me and assumed it was the mask.

[kteague]

I'm not the professional on this, but seems to me getting the leak rate optimal should precede any pressure changes. Higher pressures can bring on more leak issues and the pursuit could be like trying to catch a greased pig at the county fair. (Sorry to those who can't relate to that image.)

Kathy

[harry33]

mouth breathing often comes and goes, also can happen during part of the night only, a very dry mouth and tongue on waking is a sign of it

[RMinOntario]

Well, I taped my mouth shut last night and my numbers are still not improved. AI - 0.9, HI - 8.3, AHI - 9.2, %t in apnea - 0.3, Leak 16.8l / min. As usual, there are some areas of 0% leak. Since I never have had a problem of dry mouth or tongue, either before CPAP or after, I think the majority of the problem may be when I move during the night & my mask gets dislodged. Since it doesn't usually wake me, I'm not aware of the leaking to fix it. On occasion, when I've been on my side, I have noticed some drooling if my mouth opens, but that is not a common occurrence.

I'll tape again for a few nights at least, to verify that the leaks are from the mask.

[bdp522]

Don't forget that the resmed machines will mark more Hypopneas than other machines. If the AI is good, cut the HI by at least 1/2 to get the same numbers that you would on any other machine.

Brenda

[RMinOntario]

Thanks, the AHI is still ~ 5 with the HI halved, so would like to improve that.

I have been trialling full face masks as well, and I haven't been able to get a good seal with the Quattro, Liberty or Forma. The only way I can get a seal on the sides of my narrow chin, is to open my mouth, let it fill with air & expand. This is really not acceptable as I then have to swallow a lot of air. And each time I close my mouth to swallow, the masks start that 'farting' sound. And the air blowing into my open mouth blows on my sensitive teeth as the roots are at the surface of my molars.

I just talked to the DME and I hope to get in next week to try the Respironcs brand of masks. She didn't mention which ones she has.

[Muse-Inc]

...seal on the sides of my narrow chin...

I have a small chin too...the small mouth cushion of the Hybrid with it's small chin 'cup' fits perfectly to give me a good seal. Might trial this mask to see if you have the same good experience.

[DaleK]

[quote="bdp522"]Don't forget that the resmed machines will mark more Hypopneas than other machines. If the AI is good, cut the HI by at least 1/2 to get the same numbers that you would on any other machine.

bpd522 can you please explain this a little more? I am having similar challenges with my AHI being all over the place the last few weeks after 18 months of therapy. Maybe it isn't a bad as I think since my AI is always low, but my HI is up and down. I do feel better when my HI is about 1.5 than when it is the 6.5 it was last night. I am in the process of getting the card reader and software to be able to look at details.

Cheers, DaleK

[LinkC]

kteague has it right. Unless your leaks are well under control, raising pressure will only make them worse.

Also, a quick look at the timing between apneas and leaks will answer the leaks question.

Your AHI is fluctuating wildly from night to night. Since you say the leak rate is fairly constant, my guess is leaks aren't causing that. But may be contributing overall, of course.

[bdp522]

I'd mentally cut the "HI" in half if you're going to compare your overall AHI to the AHI people using Respironics machines talk about. I don't know this for a fact, but I believe ResMed machines tend to report as "hypopnea" a greater number of flow limited events than a Respironics machine does. It seems to me that some of ResMed's hypopneas would be called just a "flow limitation" in a Respironics machine. Anyway, that seems to be the case when I switch between brands of machines, and get equally good treatment from either but see double or triple the "HI" number reported by the ResMed machine.

with a ResMed machine, if my AI (apnea index) were 0.5 and my HI (hypopnea index) were 6.6, giving me a total AHI of 7.1, I'd mentally cut the hypopnea index in half (to 3.3) and then add THAT lesser hypopnea number to my AI of 0.5. That would give me an AHI of 3.8 instead of 7.1.

I really don't think anyone using a ResMed machine should try to chase the oft mentioned ideal of "AHI should be under 5." With a ResMed machine, I think people need to make their treatment tweaking decisions by looking at their separate AI and HI figures instead of looking at the overall AHI.

I'd want to see a very, VERY LOW AI, and then, if the HI was below 10, I wouldn't worry for a single moment about what the overall AHI was. With a ResMed machine.


High HI affecting AHI rating. Should I be worried? - topic started by ChrisC:
viewtopic.php?p=355205#p355205

CPAP: By the Numbers - topic started by ThomasMcKean:
This thread contains Velbor's chart of 3 brands' definitions of apnea and hypopnea:
viewtopic.php?p=356255#p356255

These quotes are from RestedGal. Discussions on this forum show this to be accurate.
I do not have and have never used a resmed machine, but am quite certain that RestedGal's posts are right about this.

Brenda

[Muffy]

Don't forget that the resmed machines will mark more Hypopneas than other machines. If the AI is good, cut the HI by at least 1/2 to get the same numbers that you would on any other machine

Brenda

I'm sorry, this is still not clear to me. I mean, events are events. Why are half of the events ignored? What's so different about half of the events? Are the same criteria not used?

If you were to use a Respironics machine and then a ResMed machine, back and forth, you'd probably see quite a difference in the reported AHI...mainly due to a difference in the reported HI number. That doesn't mean one brand "treats" better than another. It's purely a difference in the definition of hypopnea each manufacturer uses. It's an arbitrary line drawn in the sand.... Respironics saying "this flow limitation is still regarded a flow limitation" or ResMed saying "this flow limitation is now regarded a hypopnea" purely for the purpose of what the designer wants the machine to do next.

Has a comparison actually been done? And even if this difference exists, why couldn't it be that the Respironics HI must be doubled to get a reading of what is actually occurring?

Muffy

[rested gal]

Don't forget that the resmed machines will mark more Hypopneas than other machines. If the AI is good, cut the HI by at least 1/2 to get the same numbers that you would on any other machine

Brenda

I'm sorry, this is still not clear to me. I mean, events are events. Why are half of the events ignored? What's so different about half of the events? Are the same criteria not used?

The difference is in the definitions of events. Different definitions can make one machines "event" be another machine's "not quite an event yet." And no, the same criteria are not being used among the various machine manufacturers.

Respironics and ResMed and PB (and DeVilbiss and F&P) all use different definitions/criteria for events, I believe.

Velbor posted an interesting chart about the differing definitions for three of the manufacturers:
CPAP: By the Numbers - topic started by ThomasMcKean:
This thread contains Velbor's chart of 3 brands' definitions of apnea and hypopnea:
viewtopic.php?p=356255#p356255

Most of them agree pretty closely about what constitutes an apnea. But the different definitions between manufacturers about when a flow limitation will be called a "hypopnea" can make a quite difference in the reporting of the Hypopnea Index. And the HI is gonna affect what the overall AHI adds up to.

Has a comparison actually been done?

Not any formal scientific comparison with live people that I know of. It's purely anecdotal. Started by me, I think.

And even if this difference exists, why couldn't it be that the Respironics HI must be doubled to get a reading of what is actually occurring?

You could do that, sure. Double the Respironics Hypopnea Index, sure. But if I suggested doing that, I'd also start telling people to shoot for an AHI under 10, instead of under 5.

The point, however, is that as long as "AHI under 5" is the popular "numbers goal" (there are other goals more important than the AHI number, of course) that people are looking to achieve with CPAP treatment.....

And as long as people on one brand of machine are going to be comparing how they're doing, with what they hear that people on other brands of machines are doing......

Cutting in half the HI for one (ResMed) is the simplest way I see to accomplish both those things. Levels the machine reporting field.

Of course one machine *might* be letting more "real" events through than another does. Can't know what's "real" unless hooked up for a PSG at the same time though, can we, to note SpO2 drops, etc.

Or one machine *might* not be noticing some events as well as another does.

However, with the home treatment machines, I think the difference in AHI (particular the HI part of it) reporting most of the time comes down to just a matter of different definitions among the manufacturers for "hypopnea."

[RMinOntario]

I'm including 2 nights charts for info. July 26 was with my Activa LT and using no tape. Last night, I used the same mask & did use tape up until the 2nd bathroom break.

As you can see in the chart for the 26th (altho labeled 27th), all but 1 of my apneas occurred when I had 'no leak'. Leak was 8.4l/min. AI 1.1, HI 4.4 (pretty well my best night since I started CPAP)

Last night, I taped my mouth for the first 2/3 of the short night and every apnea happened when I had no leaks. It's very clear when I examine the data over 2 hours. Leak was 10.8l/min. AI 1.3, HI 7.8

So based on this, I would guess that the leaks are mostly from the mask. My question is how do I fix it when the leaks don't wake me to adjust the mask? Since it doesn't happen all the time, it appears that this happens when I change positions.

Thanks again for any advice.