Sierra

That is not quite classic CSR, and the machine has not flagged it as such, but it is a strong indication of instability in the control system regulating breathing rate. There are a couple of upsets right at the beginning of this zoomed in area around 3:09 and 3:10. Then it settles out until 3:14:30 or so. There is a bit of a blip in flow limitation and then that starts off the cycles of periodic heavy breathing with the flow waxing and waning. This is most likely when the feedback on CO2 levels in the blood are too slow. This causes an over correction, and that start of the cycle over and over again. Is suspect this is the basic cause of your CA events. If I could tell you a simple solution, I would. But, I have pretty much the same thing, and have found ways to minimize it, but not stop it. One of the things I have blamed it on is one of my blood pressure medications; a beta blocker called bisoprolol. This med slows the heart rate down and I think it may have been over doing it, causing my blood flow and CO2 feedback to be low and slow. I convinced my doctor to let me try half the starting dose of this medication (0.5 mg) and it seems to have helped some. But the issues for every person are likely to be different. If you cannot get the frequency of CA events down to an acceptable level (<5 per hour), it would be worth talking to a cardio pulmonary specialist about it.

It is becoming more and more apparent that like me, you are suffering from what is called Complex Apnea. That is when a significant part of your apnea is central (CA) in nature. It is difficult to treat as in general more pressure reduces obstructive (OA) events, but increases central (CA) events. With a CPAP about all you can do is find a happy medium pressure where CA and OA are in reasonable balance and the total is not too high. The standard treatment guideline for apnea is for AHI to be under 5. However, I believe in the UK they do not treat apnea, or at least will not pay for a machine, until it exceeds 15. So the AHI<5 limit may be somewhat negotiable as to what is acceptable.

If you want to do some reading on Complex apnea I suggest two credible articles that are in the Education Blog section of this website. Read the first one first, and if you want to dig deeper then go on to the second one.

What is Complex Sleep Apnea?

Complex Sleep Apnea

If you have any questions, I will try to answer.

Yes, that is more helpful. Minute Ventilation is a measure of how much air is being inhaled and exhaled over a small period of time. A high amount means that the automatic control system in your body thinks you need more oxygen. It bases this on how much CO2 is in the blood. The problem comes in when the blood flow is too slow, and by the time CO2 has reduced in response to deeper breathing, there can be too much oxygen and too little CO2. Then the body starts to reduce breathing volume. When it gets out of sync it is like a dog chasing its tail. Breathing effort goes up and down in a cycle. That is essentially CSR.

Your CA events right at 00:15 are interesting. There seems to be two CA events but the Minute Ventilation is very steady. This indicates these are not CSR type of events. But later starting about 03:15 there is another series of CA events while Minute Ventilation appears to be cycling up and down. These events may be occurring when the breathing effort cycles down to zero.

This relationship is best seen when you zoom in on the scale around those times.

That looks much better, but one night is just one night. Some suggested changes for the settings:

• I would increase the minimum pressure to 13 cm. Leave max at 14 cm. Some of your obstructive apnea events are occurring when the machine is ramping the pressure down. This will limit the pressure that it can go down to.
• If you find it comfortable I would increase the ramp start pressure to 9 cm. This gets the pressure up a little higher before the ramps ends.

You may want to consider rearranging the order of your graphs. You just left click on the title of the graph and drag it up or down. You can also scrunch the height of each graph down until it starts to mess up the title, but left clicking on the border between the graphs and dragging down. This lets you see more on one page. Your apnea issues are not much different than mine. Here is the order I have mine set up in. I don't find the Tidal Volume graph useful and push it down near the bottom. But I do find the Minute Ventilation graph quite useful. Ideally you want to see that quite constant and not cycling up and down. That can be the source of CSR and CA events. Sometimes what happens is a OA obstructive event messes up the breathing and after that Minute Ventilation start to cycle, and if it gets to the point that breathing stops, then you get a CA event. If the cycle continues then you can get one CA even after another.

I still think you should try the soft cervical collar if you think you can sleep with it. Some of your obstructive events, hypopnea, and flow limitation events (around 4:15 AM) look like they may be caused by your sleep position or a kinked neck which is obstructing the flow. If your neck is kinked then it makes it hard for pressure to keep the airway open. Reducing the kinking may allow you to lower the pressure used.

At some point, but not now, it may make some sense to try a fixed pressure. Currently it looks like a fixed pressure of 14 cm might work ok. But, leave that until it is more certain what pressure you need.

Good luck and get lost! The biggest problem is your attitude, not the A11 machine.

Yes, it is hard to tell much from this one as I can't see the pressure graph to tell what it is when events occur. I would still suggest moving pressure up to 12 minimum and 14 maximum to see if that helps. The issue may be that leaks will increase if you are not getting a good seal.

Your head position issues reminds me that some have success with using a soft cervical neck collar. It prevents kinking of the neck and possibly obstructive events. They are inexpensive and you can probably get one at a Walmart. See this link.

https://www.walmart.com/search?q=soft+cervical+collar

If you can get the frequency of the obstructive events down, it may allow lowering the pressure instead of increasing it. It could be worth a try.

From what I can see this F40 mask is similar to the F30i, except it seems to be designed to be much more flexible. It may help to prevent the mask from being dislodged from your face.

I don't have the A11 model, but the humidifier looks identical to the A10. The humidifier is not really a high tech device. All it does is divert air from the CPAP over the top of the water in the reservoir, while the reservoir is being heated. Some things to check is how much water does it use. My experience with a 9 hour sleep almost all of the water is consumed. That may depend on how dry the environment is in your home. Currently we are at about 30% humidity, so that is kind of dry and will need more water. When the machine has been in operation for a while, shut it off and take the water reservoir out. Feel the stainless steel bottom of the reservoir. It should be quite warm. If you are not using a lot of water and the bottom of the reservoir is not warm to hot, there must be a problem with the heater in the machine.

Another thing to try is the warmup feature. The idea is to select it from the menu at least 15 minutes before going to bed. It should blow a small amount of air through the hose and mask and at the same time warm up the water in the reservoir. It will indicate when it is warm on the display. Again check the bottom of the reservoir to see if it is warm after 15-20 minutes. If the heater is defective there will be no warmup.

I have been suspicious of my hose too. It never feels warm. I am on my second hose because the mask end of it got discolored and soft. It would no longer hold the mask hose reliably. It almost seemed as if it was getting overheated although I never felt it even warm. The new hose restored the fit, but it has never felt warm either. When we camp in our trailer off grid I turn off the humidifier and heated hose to save power. Most of the power used by the CPAP is for the hose and humidifier. We charge the batteries during the day with solar panels and run two CPAPs at night. I still put water in the humidifier but essentially none gets used. On one occasion when it was fairly cool (we don't run our furnace when off grid) I did get some rainout even though the humidifier was turned off. The tube was exposed to the cool air and was looped down behind my pillow and collected water. Very annoying as I had to get up in the middle of the night to drain the hose. I routed the hose under the pillow instead of behind it and the rainout at least to the point of not gurgling stopped. The point is that you can get rainout even when the humidifier and hose are turned off. At home with the heated hose on and humidifier on I never get rainout.

FWIW I have my machine on Auto with humidity set at 4 which I believe it defaults to.

I don't believe there is anything special about the A11 humidifier. You may just have a defective machine. If you still have one of your old machines, perhaps get a return approval and send this one and the hose back to ResMed for repair or replacement. We had some issues with my wife's S9 machine's DC to DC power supply. It would trip out when using it in our trailer. They sent two replacements before I gave up on them. The overload design on the power supply for this machine was obviously defective. It could not handle the extra power the heated hose and humidifier took. The problem was eventually solved when she got the A10 machine. For that one I got a DC to DC power supply off Amazon that was about 1/3 the price of the ResMed one and works just fine.

I found this video review that seems quite complete. It compares the F40 to the F30i and a couple of other masks. As a caution the mask uses magnetic clasps which should not be used if you have a pacemaker.

ResMed F40 Full Face Mask Review

I noticed that ResMed has released a new full face minimalist mask in the US. It is claimed to be more flexible in changing sleep positions while still maintaining a seal to the face. It might be worth a try. Manufacturers are always releasing new masks with claims that they are the best things since sliced bread. But, one never knows until they try it. I believe CPAP.com has a money back refund on masks if they do not work for you. Or, better still your insurance may pay for it...

https://sleepreviewmag.com/sleep-treatments/therapy-devices/cpap-pap-devices/resmed-launches-compact-full-face-cpap-mask/