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Large Leak/Low Flow Rate
Can anyone explain what is happening during the gray areas on my husband's cpap data?
I woke up one night a few weeks ago to the sound of rushing air. I thought his hose had come disconnected, but when I checked it was connected, but it appeared he wasn't breathing. He was lying on his back. I gave him a nudge and he breathed and then quit again. Finally I got him to roll onto his side and he began breathing normally again. It was like he didn't even have the cpap machine all over again. When I checked his data on Sleepy Head, there were thee gray areas that corresponded to the times I had found him like this.
After getting the SD card to and talking with the doctor a couple of times, he increased his pressure to 20. Things seemed to be better until the past couple of days; he has been waking up with headaches again. So once again I checked his data and they gray areas with the low flow rates are back.
Any ideas what's going on?
Hoping the screenshots come through...
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The resolution of the screenshot could be better. Try this http://www.apneaboard.com/wiki/index.php...pnea_Board

Your husband is using an amazing fixed 20 cm CPAP pressure. That is the maximum output of the machine. Is that consistent with his prescription?

The gray areas are leaks so large the machine cannot detect events or get feedback. It appears to be related to REM or sleeping on his back. How does he feel his sleep was? What mask is being used? The machine is a Philips Respironics Aflex. You can find a 3 digit model on the bottom, for example: REF 450P. Let us know what it is, and we'll round up a manual for you.
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Screen shot is low resolution and difficult to read.
That said, somewhere there is a huge leak.

I see a full face mask -- so, it's not an open mouth problem.

Check the hose, connections, and there is an anti-asphyxia valve in the full face mask -- it's a flapper with a big vent hole. Make sure the anti-asphyxia valve is closing under pressure.

Is there anything that's old -- like mask, hose, et cetera. Sometimes a machine can leak at the humidifier. I see it's a Phillips and I'm not very familiar with Phillips. ResMed S9's have a humidifier gasket that can leak if displaced or degraded.

Pressure of 20 cm-H2O can blow an old part like the hose.

You must find the leak or get professional help with it; the therapy is totally worthless with such a large leak.

edit: What odd is that it seems to terminate for awhile -- very odd.

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Sorry about the resolution. It's my first time posting a screenshot here. I did use that website, but possibly not correctly.
His previous setting was 16 - 20 on auto-pap. The doctor was the one who recommended 20 straight as a new setting.
He has been waking up with headaches again. He never really feels rested and/or energetic.
The mask is Res Med Quattro Air Full Face Mask.
The machine is a REF 550P.
The mask was replaced January 25th, that includes the valve. I'm not familiar with how the valve should work. I have a nasal mask myself.
I put a new hose on today. That was MUCH older.
I updated my profile to his information.
The gasket in the top of the humidifier looks a little questionable. I'm going to clean it and see if it makes a difference tonight.
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That leak is probably bad enough to make his therapy ineffective.

If it goes away when you nudge him, it's probably a leak between the mask and his face.

However, get him to mask up, turn on, and try to wiggle connections and such and see if you can get a leak.

Janknitz's "Taming the Mirage Quattro" might help.

On suggestion I have is to put the mask on, start the CPAP and then try to relax and make the mask leak. Then adjust to stop the leak. I find that I tend to flex my face to stop leaks when awake, but then when I fall asleep my muscles relax and I start leaking again.
Get the free SleepyHead software here.
Useful links.
Click here for information on the main alternative to CPAP.
If it's midnight and a DME tells you it's dark outside, go and check it yourself.
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A pressure of 20 is really hard on mask leaks, and difficult for some people to tolerate. Many patients are prescribed bilevel when those pressures are prescribed. What was his AHI when he was using 16-20? I wish I had the answer to the mask leaks, but the article posted by Archangle above "Taming the Mirage Quattro" is one of the best on the subject.
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I have some experience with such large leak curves with a Quattro Air. For me, I would do the mask fit check on my PRS1 60 series Auto with the Quattro air and go to sleep. A couple of nights, I had such large leaks. One of them woke me up and turns out the mask was leaking near the nose area.

Since the anchor of Quattro Air is on the forehead, sometimes during the night, if your forehead swells up or your front sinus get drained or multiple other reasons, the Quattro Air may lose its seal. This is compounded in this particular case by very high pressure so there is not much tolerance in the system to resist small changes to facial topography.

You can try a Resmed Airfit F10. Its top anchor has moved down to the nose and cheek area from the forehead. This makes it less prone to leaking due to changes in facial topography during the night. I have that mask too and I have generally found it to be more forgiving than the Quattro Air. And both these masks share the same cushion and mask elbow SO you can try it for cheap by buying the headgear and the frame on eBay.
PRS1 Auto & Dreamstation Auto w/ P10 and straight pressure of 7cm. 
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I cannot for the life of me figure out how to add the attachment of the screenshot!! Says I've reached my attachment quota.
I /we wish every night could look as good as last night!
To answer your questions... before changing to 20cm his 14 day AHI was 2.45 with large leaks on many, but not every night. One night he had a leak of 108 minutes, then things returned to normal. Since changing to 20 cm, excluding some days with faulty readings due to a card issue, his AHI is 4.02. That being said, he also has had no RERA since the increase in pressure.
Today we will go through the mask fitting video and do that. I think that may be an issue. Every time I tell him his mask is leaking (buzzing) he tells me he has it as tight as he can get it. Now I understand that is not the answer to the leaks.

I also understand, thanks to the experience of the members here, that when he is having these leaks the machine cannot read properly.
However I'm still not convinced that his lying on his back and not breathing (normally) isn't causing the machine to think it is having large leaks. If one stops breathing or breathes very shallowly, the air has to go somewhere, right?
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BTW, last night he had just 5 hypopnea, 6 obstructive for an AHI of 1.71. No large leaks or anything else!!
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That leak is so large that you should be able to hear it. Is his machine set so that it shuts off automatically when the mask is removed? Because my guess is that he's removing the mask while asleep and has no recollection of it. Unfortunately the only rememdy for this is extra homemade straps and bobby pins!

It seems that if the leak were a gasket or something like that it would be continuous. Instead we see it going up and staying there for an hour or so, then going back down. Perhaps his mask is ajar, but again you should be able to hear the resulting leak.

As others have noted, with a leak that large the machine can't report reliable flow rates or AHI. It's also rendering the therapy ineffective, which would lead to the symptoms you mentioned.
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