Leak rate question

[Jalex570]

Hi, I'm a 35 year old male diagnosed with mild-moderate obstructive sleep apnea about 6 months ago (AHI 14/18 for non-rem/rem sleep on overnight study).  I'm 6'0" 155 lbs, my ENT doctor said he's surprised I even have as much apnea as I do given my weight.

I have a question about leak rates.  I've been dealing with troublesome aerophagia the entire time.  Sleep therapist lowered my pressure from 8-16 to 6-14 and changed my machine to level 2 EPR.  It was impossible to tolerate without EPR, and they switched me to a Full Face F10 mask because I was breathing out my mouth apparently.  If it wasn't for the aerophagia I wouldn't have a problem with CPAP at all... the mask itself doesn't seem to bother me.  I'm going to see an actual sleep doctor soon about possible oral devices (as a backup) and machine adjustments.

Question is... last time I saw the sleep therapist, she said my leak rates were a little high.  I noticed she was pointing to the "95 percentile leak rate" on the printout which said 31 L/min.  However, my everyday leaks rates for the last few days are (Myair data):

13.2 L/min
7.2
4.8
13.2
3.6
4.8
6

I believe this is from side sleeping/mask hit by pillow.  So is my sleep therapist off base?  I thought it was the average that was supposed to be below 24 L/min, not the 95 percentile. I asked her about the difference, but she didn't really explain it and just said they like to see it lower. I don't seem to notice many leaks at night.  My corresponding AHIs:

4.8 events/hr
3.8
2
1.4
1.9
2.1
4

It varies, but generally around 2-3 AHI.  I haven't noticed a real significant improvement since starting CPAP (5 months). I thought I slept well before until a friend told me I gasped at night sometimes. I do seem to sleep ok, dream ok, and wake up fairly refreshed most days.  Just frustrated because the aerophagia is on occasion painful.  This is not a fun process as I am a bit of a hypochondriac already. Thanks for any opinions.

[Beej]

I'm wondering if using a chin strap with the nasal mask or pillows might work for you. Did they offer that solution? It might or might not work with the aerophagia.

Something that may help with the issue - From member OpalRose
"Start practicing keeping your tongue to the roof of your mouth.

Place your tongue to roof of mouth with tip of tongue behind front teeth, then gently suck upwards.
This places your tongue in a natural position and seals the back of your throat, so that no air can escape if your mouth falls open. You can practice during the day too. It takes some time, but will work if you're persistent. I was able to get rid of my chin strap after a couple months once I perfected this. It's worth a try. "

[srlevine1]

From my experience:

(1) While I want a low a leak rate as possible, I am not worried about anything below 24 L/S per ResMed's recommendations. Each manufacturer has their own way of calculating leak rate, so you may want to read your machine and mask manuals for a more definitive answer.

(2) Make sure your mask type is dialed into the machine as it can affect how leak rates are reported -- all masks leak to expel carbon dioxide -- and each manufacturer has different leak rates for different masks. Leak rates are a function of the pressure and the mask characteristics.

(3) If you are experiencing a high leak rate, you may not getting be adequate therapy and the events that are recorded during periods of high leakage are questionable.

(4) I had the same problem with side-sleeping and mask slippage (made worse by a beard) and solved my issues with a ResMed Mirage Activa LT nasal mask. Pressure is 12 -15.6 with an EPR of 3. Anecdotally, with EPR off, my AHI appears to double.

(5) Your weight is only one factor. Neck Size is another. Throat geometry and physiology is another. And, let us not forget the brain farts that cause Central Apneas.

(6) Median values are worthless for me and I always use percentile readings. The percentile calculation indicates that the leak was at or below the calculated number for 95% of the night whereas the median is simply the midpoint of the value set and means virtually nothing to me.

(7) Remember individual observations are snapshots in time and it is the trend that concerns me.

Best of luck taming the leak monster.

[trish6hundred]

Hi Jalex570,
WELCOME! to the forum.!
You could try elivating your head a bit with pillows, or even raising the head of your bed to help with the aerophagia.
Sometimes people have to get a different type of machine if the things I mentioned above don't improve the situation.
Hang in there for more responses to your post, good luck to you with your CPAP therapy.