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Flow rate interruptions and prolonged flat segments in the Flow Limits graph, but no AHI's recorded.

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ittiandro +0 points · 2 months ago Original Poster

The attached Sleepy Head Daily Report shows only one Hypoapnea event in the Event Flag graphic, but the Flow Rate shows two blanks or gaps between 22:30-22:40 and a longer one between 23:40-00:20, i.e 40 min. The Flow Limit graph, too, shows two flat segments at the corresponding time zones. If these blanks and flat spots indicate restricted air flow or disrupted breathing for some reasons, why do they not show as apneas in the Event Flag graph, at the corresponding time.

I hope the Report shows.

Thanks

Ittiandro

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Sierra +0 points · 2 months ago Sleep Patron

This has every indication that the CPAP machine was totally off during those time periods. When it comes back on again you can see that the pressure is in the AutoRamp mode and is held constant until you fall asleep (or at least the machine thinks you are asleep). This also indicates the machine has been off and the AutoRamp starts again when the machine comes back on. Just before the second off period you can see a high leak rate spike which suggests the mask has come off or the hose disconnected. Do you ever wake up with the mask off, or hose disconnected?

You may want to check your electrical connections to see if any of them are loose. Your first event does not show a high flow. It just goes off. If you zoom in on it you could see if there is any indication of a flow spike

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ittiandro +0 points · about 2 months ago Original Poster

Thanks Sierra

  1. Yes, it may be because the machine was off while I went to the bathroom, but it shouldn't be for 30 min, unless I forgot to put the mask back on right away. I'll check and make sure.

  2. I attach a graph from last night. It shows 2.07 AHI’s , well above my usual avg of about .50. 2.07 AHI's is still quite O,K., but the graph also shows LL for 26% of the total sleep time, i.e. into the red zone. It is not the first time. Usually, I wouldn’t worry if I feel well, but lately I’m tired at wake up. It could be that there are more than marginal AHI’s that the machine does not record because of the LL and this could affect my sleep.
    I’ll speak to my respirologist, if this persists. In the meantime, I’d appreciate if you can look at the graph, because I think I found some incongruities More importantly, looking at the Flow Rate graph, it is at 0( or almost) for approximately 4 minutes and the Flow Limit graph goes flat for longer than 4 minutes, i.e. for most of the time zone of the LL. Does this point to some kind of breathing irregularity, or outright interruption, if only intermittent? If so, I wonder why there are no recorded AHI’s for most of the LL time zone.

Thanks as usual

Ittiandro

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Sierra +0 points · about 2 months ago Sleep Patron

Most of your AHI is from hypopnea which occurred right after you went to sleep. It would be helpful to click on that triangle beside the date to suppress the full month calendar. That will expose more detailed data on the left. Also it is helpful to show the Pressure and Mask pressure graphs. There is no need for the Respiration Rate and Minute Volume.

The Flow Limitation is ideally zero. It is a measure of the air flow resistance. Your numbers are higher than expected for parts of the night.

Your leaks are too frequent. What mask are you using? What have you tried to reduce leakage? As I have said before the machine will not report events during the gray Large Leak periods of time. You have to expand the scale and look for them manually. Use the up down and left right arrow keys to expand the scale during the grayed out periods.

That period of time around 23:30 appears to be when the machine is off.

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ittiandro +0 points · about 2 months ago Original Poster

Thanks by clicking on that triangle to suppress the month's calendar, there are no more details than previously. The mask is an Air Fit F 20 L. I had it for about a year. I noticed that washing the silicone seal and my face every night improves the leaks, just as shaving. My beard is not very strong, but I found that even a short unshaven stub can let air through the seal. The velcro straps, especially the lower one, are probably a bit worn and they would come off easily. I didn't think it was time to replace the silicon seal and/or the straps, though. I fastened them with tape after setting them comfortably and now they stay on, even though there is some air still leaking when I move the face or the jaw.
Here are the Pressure and Mask pressure graphs. What is the difference, anyway?

Thanks

Ittiandro

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Sierra +0 points · about 2 months ago Sleep Patron

Actually there are more details when you suppress the full month calendar. You of course can see them by scrolling up and down, but when you do a screen shot all I can see is what is in the screen shot, and nothing more. I can't scroll a screen shot. In any case I can see more now. I was curious to see if you still had EPR turned on and what it is set at. I see it is full time and at 3 cm. That is good.

The only easy change I can see is to increase the Ramp Start pressure. It now appears to be set at 10 cm. You could increase it up to your minimum pressure of 12 cm. That initial set of hypopnea events occurred while pressure was ramping up. You may avoid some events by starting the pressure at a higher value.

I have a F20 mask and gave up on it. I could not make it seal well. So I can't really give you any advice. Some have used a cloth mask liner called RemZzzs. Others make their own using t-shirt material. They claim it stops leaks....

The difference between mask pressure and just pressure is that the mask pressure is measured and fluctuates as the actual mask pressure fluctuates. The other pressure is just the set pressure that the machine is trying to achieve. It is very steady as it is just the pressure that the machine wants, not what it actually is.

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ittiandro +0 points · about 2 months ago Original Poster

I tried to remove the calendar again, but there are no more details than those already shown with the calendar on. I increased the Ramp start pressure to 12 as suggested, but I don’t quite understand because the pressure is already set at 12-16, so the machine should already work at 12. I enclose last night’s report. It shows quite a high % of LL, around 57%, the highest so far. On a closer look, I find a few oddities. The total sleep time is only about 4 hrs. In reality, it is longer than that, because I recall waking up with the mask still on at about 6 a.m. I then removed it and continued to sleep without it until around 9 a.m. The type of mask in the Resmed machine showed as pillows, instead as full face. I don’t know if this has any bearing, but I corrected it. The humidity level is set at 5, but last night I had an unusually dry mouth and this morning I found some water in the tank, which is usually empty. Thanks

Ittiandro

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Sierra +0 points · about 2 months ago Sleep Patron

On the screen format, I would also suggest turning off the pie chart display. It adds no useful information and takes up screen space. Just go to File, Preferences, Appearance, and UNCHECK the box called "Show Event Breakdown Pie Chart". This will allow more to be displayed on the left. Some missing information now are the "sessions" near the bottom this is helpful in determining if you are missing part of the night.

From what I can see it appears your start pressure is still set at 10 cm. That part is missing too under the Machine Settings, as it is cut off. That flat red section of the Pressure chart indicates your start pressure on the graph.

Having the mask type set on Pillows instead of full face could make the leaks look worse. A pillows mask has a lower purge flow than a full face. Yes, you should have it set at Full Face.

On humidity, I have a heated hose, and have my humidity control set on Auto. It takes over 9 hours to use up all the water.

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ittiandro +0 points · about 2 months ago Original Poster

Thanks

The LL seem to be ongoing I ordered mask liners from Amazon, hoping they will fix the problem. Last night’s report, too, shows them at 30% above the red mark, with only 0.67 AHI’s, but none in the LL area. I don’t know if they are hidden, which would make the report inaccurate.

The LL statistics are: Min. 0.00, Median 6.0, 95%= 38.4, Max 51.6

Flow limit : min 0.00, Med. 0.00, 95% 0.12, max 0.69

I increased the Ramp Start . Now on the machine display, the Start Pressure is 12 , with Ramp time =auto, but the Sleepy Head report shows Ramp Off.

I don’t know if you need the report for further comments. If you do, let me know. I don’t want to take up too much of your time.

Thanks

Ittiandro

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Sierra +0 points · about 2 months ago Sleep Patron

The only way to tell if there are events during the large leak grayed out areas is to look for them manually. There will be no event flags. You have to left click a few times at the beginning of the gray area to zoom in far enough to see 10 second gaps in the flow rate. Then use the left and right arrow to scroll across and examine the whole range of the time. The up and down arrow keys can be used as well to get the right amount of zoom.

Sleepyhead has a bug and shows that the Ramp is Off even though it is on. This may have been fixed in OSCAR.

Feel free to post more daily reports for comments.

I can't remember if you have tried other masks like a nasal pillow. They do require you to keep your mouth closed during sleep or to tape your mouth closed. They tend to leak less. The ResMed AirFit P10 is a good one. Another option is the F&P Brevida. It has better headgear than the P10. But both require the mouth to stay closed.

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ittiandro +0 points · about 2 months ago Original Poster

I enclose today's report again, with maximum zoom on the Flow rate graph, showing 5 secs spans. I don't know how to interpret it in reference to the Large Leaks and possible hidden AHI's , if any. For one thing, I see no additional AHI events under the LL sections or anywhere in the event flag graph, even with max zoom. . Does this mean that there are no hidden AHI's ? Where would these hidden AHI's show at max Zoom level, if any?

Regarding the LL issue, I conducted a retroactive search since I began the therapy in June 2020. It appears that these LL started cropping in mid June 2021, intermittently at first and then picking up in number and duration. I never tried other masks, but I can only breathe through the mouth, due to a almost permanently blocked nose and polyps on the throat., so I cannot use either pillows or the other masks you suggested. My doctor knows that I cannot breathe through the nose, but the therapy has been so far successful, unless the large leaks issue has a negative bearing if it continues. I'll see how it goes with the liners. If worse comes to worse, I'll have to replace the silicon seal.

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Sierra +0 points · about 2 months ago Sleep Patron

Start by zooming in on a flagged OA event. Then you will see what an OA event looks like on the flow graph. Then you have to scroll through the whole grayed out area while zoomed in to see if there are any similar looking events where flow stops or almost stops for 10 seconds or more.

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ittiandro +0 points · about 2 months ago Original Poster

OK, thanks for the hint. Anyway there were no LL last night, may be because I slightly retensioned the left strap which had a little more slack than the right one.

Ittiandro

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ittiandro +0 points · about 2 months ago Original Poster

I received my Respironics Mask liners from Amazon. I put one on last night. A bit uncomfortable at first, because of the thickness of the fabric and also the size of mouth opening on the fabric, somewhat small, I thought. It touched my lips. But I could breathe OK and it didn't bother me during the night. The large leaks were however worse than ever. Practically uninterrupted from 3:30 to 6:30, some lasting 60 min, a few 30 and 40 min, for a total of 46% of sleep time. I don't know if it is because of the liners. I decreased the Ramp setting from 12 back to 10. See how it goes. I'm still not too sure how to read the Flow rate in connection with the LL. . I zoomed it max. THe AHI's are minimal, even by zooming. The Flow Rate waveform goes from +180 to - 120. I don't know what is the relevance of this amplitude.. I think these LL affect my sleep in a subtle way. I don't know if these machines go out of adjustment and need to be re-calibrated. I'll contact the sleep clinic to see if there are adjustments to be made or perhaps have the seal replaced.

Here is the graphic, if you can glean something that I don't see..

Thanks

Ittiandro

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Sierra +0 points · about 2 months ago Sleep Patron

I can't add much. The scale is zoomed it a bit too much to tell what is going on. But, yes the leaks are still high.

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