(07-05-2014, 06:13 AM)Don in Austin Wrote: Last night:
Of this, (with apparent rounding errors):
.3 Obstructive --
.9 Central --
Unknown apneas are scored when the machine can't tell what they are because the data from the FOT algorithm for detecting CAs is ambiguous.
Usual reason the FOT fails is largish leaks and official Large Leaks.
Quote:Is this because my lips keep blowing open? False readings?
Using nasal pillows.
If the lips are blowing open, then air is getting into your oral cavity and escaping out through the open lips. With the high "Unknown Apena Index" that points to serious leaking going on through those open lips. The Unknown events are likely REAL events that are happening when your leak rate is too high for the FOT algorithm to work. And your leak rate is too high because of the air blowing out the open lips.
You also write that your settings are:
So your EPAP ranges from 4 to 7 and your IPAP ranges from 7 to 10. Does the problem with the lips blowing open happen mainly when your pressures are 10/7 rather than when they're closer to 7/4? Also how much time are you spending at 10/7 and what do the leaks look like at 10/7?
A narrower pressure range might help, but that probably means increasing
the min EPAP so that you start the night out closer to your max pressures.
Quote:A chin strap has been suggested, but my dental device already keeps my mouth shut.
The dental device may be keeping the jaw
shut, but it ain't keeping your tongue up on the top of the roof of your mouth and your lips closed.
Here's the thing you need to be aware of: Tongue placement is critical when it comes to keeping the CPAP air out of the mouth
in the first place. When at least the front 1/3 to 1/2 or so of the tongue is firmly pushed up against the roof of the mouth just behind the top incisors, it effectively seals off the oral cavity from the upper airway.
You can test this yourself: Put the tongue where I describe, open your mouth (while keeping that tongue firmly up on the roof of the mouth) and continue to breathe through your nose. If you start breathing through your mouth as soon as you as open your mouth, the tongue is NOT yet in the right spot. Once you are breathing through your NOSE with your mouth open, pinch your nostrils shut and you should find that it's hard to impossible to breath until you MOVE the tongue.
Once you know where that tongue needs to be to block the oral cavity, you need to train yourself to keep it there during the daytime when you are breathing through your nose. This sounds more complicated than it is: The natural tongue position for most nasal breathers is what I'm describing. And so all I'm telling you to do is to try to figure out whether your tongue does what it's supposed to naturally or whether you're doing so much (daytime) mouth breathing that the tongue has decided its natural spot is not up on the roof of the mouth.
Until you can train that tongue to stay where it belongs, it's worth trying the chinstrap. But to be honest, the chinstrap may or may not help in keeping the lips closed and that's the problem. Taping (if you're brave enough) may help.
Quote:A big problem with round one of CPAP was trying to use full face masks. I don't have too big an issue with the fit or comfort of the nasal pillows.
If you want to use nasal pillows, then you have to address the leaks coming from your lips since they are large enough to prevent the machine from accurately scoring the data. My guess is that you also had a large number of Unknown Apneas because the machine was having trouble keeping your airway properly pressurized due to the large leaks.
Quote:Should I duct tape my lips? Doesn't seem good, somehow.
Duct tape, no.
But there are folks who use a bit of SKINNY blue painters tape (or other kinds of tape that are EASY to rip off the skin). Usually idea is to put one or two VERTICAL
strips across the lips. One piece right in the middle (where the sides of the lips are NOT covered) OR one piece on each side (where the middle of the lips are NOT covered).