FFM Causes Higher AHI Than Nasal Mask-Why?

The size small Simplus FFM causes higher AHI than the Mirage FX nasal mask. What is going on with this?

With the FFM I tape from one lower strap, go under the chin and come up to the other strap. This seems to hold the mask down and it doesn't creep into my mouth during slack jaw. I need a more elegant solution and have some ideas from others on the board. I only wear the FFM when I'm too stuffed up to breathe through my nose.

Simplus FFM causes higher AHI than the Mirage FX nasal mask

What are the numbers? What AHIs are being compared?

A jump to 10 from 3 is of concern.

A jump to 2.0 from 1.4 is insignificant.

I only wear the FFM when I'm too stuffed up to breathe through my nose.

The simplest answer is that your AHI numbers are higher were you are stuffed up.

Are you changing the mask type on your machine, when you switch masks?

Some of the experts over on binarysleep say that FFM's increase your AHI.

The logic is that the FFM pushes on your lower jaw. This can push your jaw back, which narrows your airway. It's sort of like a dental appliance in reverse.

The explanation makes sense to me.

It's hard to know if this affects most people or just a few, and how severe the change is. However, it's possible that a FFM may make your AHI worse, so experiment with it to find out what happens to you. It might still work OK if you increase your pressure a little.

That would be an interesting experiment. Full face mask wearers try wearing one of those head things that keeps the jaw closed for nasal mask wearers. But then how would you breath through your mouth?

I'd give it a try but it sure gets away from being minimalist.

JimP wrote:one of those head things that keeps the jaw closed for nasal mask wearers

???????????

I just got a nasal pillow mask to replace/supplement my full mask and recorded my lowest AHI ever. Maybe there is something to this.

ChicagoGranny wrote:

JimP wrote:one of those head things that keeps the jaw closed for nasal mask wearers

???????????

These devices. https://www.cpap.com/cpap-mask-parts/cp ... straps.php

So it's not just me. I wear a chin strap with the nasal mask so that the jaw doesn't drop and I don't breath out of my mouth. I don't want to use it with the FFM because I don't want to train myself to mouth breath with it. Then when I return to the nasal mask I may continue to mouth breath, defeating the purpose.

Last night for example with the FFM lower straps held in place with tape the leak rate was 35L/min. With the nasal mask a couple of nights ago it was 4L/min. And to add insult to injury 3 hours of the FFM only registered as 1 because the dang thing still migrated up into my mouth. The machine must have "thought" that I'd taken the mask off. Sheesh!

ChicagoGranny wrote:

Simplus FFM causes higher AHI than the Mirage FX nasal mask

What are the numbers? What AHIs are being compared?

A jump to 10 from 3 is of concern.

A jump to 2.0 from 1.4 is insignificant.

jaycee2 wrote:So it's not just me. I wear a chin strap with the nasal mask so that the jaw doesn't drop and I don't breath out of my mouth. I don't want to use it with the FFM because I don't want to train myself to mouth breath with it. Then when I return to the nasal mask I may continue to mouth breath, defeating the purpose.

Last night for example with the FFM lower straps held in place with tape the leak rate was 35L/min. With the nasal mask a couple of nights ago it was 4L/min. And to add insult to injury 3 hours of the FFM only registered as 1 because the dang thing still migrated up into my mouth. The machine must have "thought" that I'd taken the mask off. Sheesh!

You remain somewhat of a mystery, in part because we don't know the AHI comparison.