Seems like mask type makes a big difference to AHI

[brain_cloud]

I didn't used to think that FFM vs Nasal really made a difference to me therapy-wise, but now I'm pretty sure I was wrong about that.

After switching from Nasal to FFM early on in my CPAP experience (for comfort reasons only), I have recently been testing out Nasal masks again. Here is a summary chart:


The last bar is from last night when I tried to use CPAP-cap in conjunction with the Quattro, but still didn't results like my recent ones with the Activa. Here's a nasty cluster worse than anything I've seen using the Nasal mask:



The next test will be to use the Quattro with mouth tape as well to see if that makes a difference.

[who]

Leak charts?

[brain_cloud]

Leak charts?

Worse on the Nasal than the FFM.

[SleepingUgly]

The last bar is from last night when I tried to use CPAP-cap in conjunction with the Quattro, but still didn't results like my recent ones with the Activa. Here's a nasty cluster worse than anything I've seen using the Nasal mask

I didn't follow... That second graph with all the events was using a nasal mask, not a FFM, right?

The first graph showed your AHI was lower with the nasal mask rather than the FFM, right? But you're saying your leaks are too high with the nasal mask?

[brain_cloud]

The 2nd graph was last night, using an FFM. However, leaks are better using the FFM, but AHI is worse.

[GaryG]

There are so many variables involved. How was your day? What did you eat before going to sleep? When was the last time you ate before going to sleep? Did you have a cold? Were allergies acting up? etc etc.

Could just be you are more comfortable with a nasal mask, hence more relaxed. I'd hesitate in over analyzing (note this advice is coming from an over analyzer).

[GumbyCT]

The 2nd graph was last night, using an FFM. However, leaks are better using the FFM, but AHI is worse.

AHI will be better if the machine can't sense events do to leaks. So yea, AHI tends to increase as leaks decrease UNTIL you get to the right pressure(s).

Life is all about balance.

[SleepingUgly]

In the presence of leaks, do AHIs tend to be lower, higher, or random?

[kurth83]

My ahi varies from .4 all the way to 3.5 with the same mask, so unless the results were dramatic,
I would need a few weeks worth of data to detect a small difference.

[brain_cloud]

My ahi varies from .4 all the way to 3.5 with the same mask, so unless the results were dramatic,
I would need a few weeks worth of data to detect a small difference.

My AHI on FFM varies from 2.0 to 14.8 with a mean of 6.0 (eyeball)
My AHI on Nasal varies from 0.9 to 3.2 with a mean of 2.0 (eyeball) on 10 days of data

That seems like a pretty big difference.

But I just found the smoking gun (not the smoking chimp!) in pictures. Which I'll post tomorrow.

[brain_cloud]

These pictures are from June 25, which is the last bar on the first chart in the first post, and also from the time of many events shown in the second chart from the first post. I'm using the cheapo method for recording yourself sleeping described by Bob3000 which works great. My face is obscured due to my setup that night, which is Quattro + CPAP-cap + impromptu eyemask to keep out the light from the LEDs.


OK, here I am at 2:29, just prior to the big bunch of events (there's a 6 minute or so difference between the image label time and the Resmed time). What a little angel; sleeping on my side. Then all hell breaks loose:




I've flipped onto my back where I will stay for the next 45 minutes. By the way, there are two hard croquet balls attached to the back of my shirt. I guess my bed is too soft.



My arm moves around alot. It keeps going up to my head.



This also is a position my arms go into when I'm on my back. I call it "The Spider".



The knees also go up and down during this period.



And then I flip back onto my side and everything quiets down again. This doesn't just tell me that my bad stuff is when I get on my back. I also have recorded several of the days when I was using the Nasal mask, and during those nights I also flip onto my back for long periods of time. BUT, there are not clusters of apneas when I am on my back using the nasal mask. I think that means the therapeutic pressure required to control apneas while in the supine position is different when I am breathing through my nose vs when I am breathing through my mouth. Or something like that.

Last night I went back to the Nasal and got a 2.2 AHI. Tonight I will use the Quattro but tape my mouth shut.

[-SWS]

I think that means the therapeutic pressure required to control apneas while in the supine position is different when I am breathing through my nose vs when I am breathing through my mouth. Or something like that.

That might be right. One difference between the nasal mask and the FFM is that the latter can apply more strap pressure on the chin. And those additional apneas are all differentiated as obstructive.

Tell you what I'd try next: 2 more croquet balls and half-a-mallet. Just kidding. Seriously, I'd try to experimentally stabilize the mandible forward while using the FFM with one of these: viewtopic.php?f=1&t=53060&p=490941&hili ... rt#p490941

If obstructive AHI drops, then you'll know FFM strap pressure on the mandible was the culprit---specifically during supine sleep [edit: very good alternate possibility here]. Good luck with croquet and sleep!

[brain_cloud]

Thanks -SWS. Alternatively, I will consider having my back removed surgically. Once it's gone, I won't be able to roll onto it anymore.

[DreamOn]

brain_cloud, I had the exact same experience with the Quattro FFM vs. Activa LT nasal mask. Many more apneas when on my back with the Quattro! I do believe that the Quattro bottom straps were pulling my jaw back. I tried all sizes, and none worked for me. You can read about my Quattro Experiment here (with charts): viewtopic.php?f=1&t=48909.

I tried a boil-and-bite mouthpiece, but that didn't work for me at all. I have a severe overbite, so it didn't fit right, and I was also concerned that my teeth would be adversely affected. I reluctantly gave up on the Quattro (and other full-face masks), but now that I have an APAP machine I'll probably try it again in the future, to see if it'll adjust the pressure. My S8 Elite II CPAP machine couldn't do that.

[Jay K]

I will consider having my back removed surgically. Once it's gone, I won't be able to roll onto it anymore.

Not only would the procedure keep you from rolling onto your back, it is also a proven weight-reduction technique. Sort of an apnea-prevention twofer.