Sierra

One of the things you may want to try is setting the machine into CPAP mode and going to a fixed pressure. That way you take control away from the machine and not let it increase pressure too much. In my case when I had it in auto mode it was responding to hypopnea events with more pressure while the hypopnea events were actually incomplete central apnea events. Then more pressure makes the central apnea worse instead of better. That is why I went to a fixed pressure. It did a good job of reducing AHI and in particular central apnea. However it did not improve hypopnea. More recently I have turned EPR back on with it set at 2 cm. That has virtually eliminated my hypopnea events. Not sure how and why, but I have a little suspicion that EPR is doing enough to prevent the machine from flagging events, but not really changing my breathing much at all. Numbers improved, but perhaps outcomes not so much. It is nice to see lower numbers though!

As you will know 8 cm of pressure is pretty low. A CPAP goes up to 20 cm, and a BiPAP which many use will go up to 25 cm of pressure. I now run my AirSense 10 on a fixed pressure of 11, with it set to use 9 cm during the AutoRamp period. I find the pressure refreshing, and anything less than 9 while I am awake kind of suffocating. I don't like to feel short of air when I take a quick deep breath. I am amazed that some people can tolerate a 4 cm pressure to start the ramp.

I have issues with central apnea and have blamed the bisoprolol beta blocker for some of it. I was taking 5 mg a day and felt it was slowing my heart and blood circulation too much, and the oxygen/CO2 balance which controls the reparatory rate was unstable. This in turn I believe was causing the period breathing or Cheyne–Stokes pattern, and central apnea events. I reduced my dose to 2.5 mg a day as a test and I believe my central apnea frequency improved quite a bit. I showed my doctor the results and he agreed with the dose change as my blood pressure was still very good, but I think was kind of skeptical of me blaming the beta blocker for causing the central apnea. With OSCAR you can see all of this data displayed graphically, and can zoom in on the detail. There is a condition called treatment emergent complex sleep apnea where someone new to a CPAP experiences high levels of central apnea when first using the machine. In most it goes away after a few weeks. For me it did not. I believe the underlying cause is that the CPAP upsets the control system stability. The solution is to keep the pressure as low as possible but still control the obstructive apnea. Here is clip from the graph that shows what it looks like in OSCAR.

So in some situations CPAP pressure can be an issue. I am just not sure how to connect it to edema though.

First off, to be clear I am not a doctor. I have used CPAP for a couple of years and my wife longer. I can't think of any direct way leg edema could be caused by the CPAP. I would be looking other potential causes like a blood pressure medication such as amlodapine. A water pill like indapamide may be a better alternative. There are a few other drugs which may cause it like Actos and Avandia for diabetes. Congestive heart failure can also cause it.

Have you used OSCAR to look at your AirSense results in more detail? It may offer some clues as to what may be going on. Low blood circulation can cause central apnea. If you are having central apnea events that may be a potential cause.

I have never used Rescan but am aware of it. I have used SleepyHead for a number of years. From what I know of Rescan, SleepyHead is just as good. SleepyHead has been replaced by OSCAR, which from what I can tell is pretty much identical to SleepyHead. I have not bothered to switch but when users post their daily reports they look identical to me.

Rescan is only made available to sleep medical professionals and I am not aware of where you could download it legally, unless you are a professional.

SleepyHead and OSCAR work fine with the S9 and A10. My wife has a S9 and I use an A10 Auto. All but the most basic ResMed CPAP have a SD card and work similar to the S9.

Yes there is no problem accessing the clinical settings on the A10. You just hold the Home bar and set button down together for about 5 seconds.

What would be best to do is download OSCAR and download all the data on your S9 SD card to OSCAR now. It will give you a feel for the software, and when you do upgrade all the data will be seamlessly integrated together so you can go back and compare your A10 readings to your S9.

Be aware that based on previous history of machines ResMed seems overdue in replacing the A10 with a new machine. If you want the latest and greatest machine it may be worth holding off for a while. That said the only thing I have against the A10 is that it clunky to turn on the prewarming feature. It should be one button, but it is buried in the User Menu instead. The other option may be to watch for sales on the A10 as at some point dealers will want to clear them out before a new model arrives...

And one other thing. The ResMed A10 comes in two models . One is the standard and the other is the For Her. The For Her version does everything the standard version does, but also offers an additional mode that is more response to flow limitations and elevates pressure faster. That and it is a different colour. The price is the same for both. I am male but if I was buying again, I would get the For Her version just for the additional optional mode.

There are many different causes of complex sleep apnea. Dr. Robert Thomas that has written an article about it in the Education Blog section here.

Complex Sleep Apnea

First off, I have very limited experience with BiLevel machines. They do seem to have a purpose but it seems to have more to do with respiratory issues rather than obstructive or central apnea. On the auto pressure thing, my thinking has evolved. On the surface it seems that an auto machine is a great idea as it just uses enough pressure to do the job and no more. And then when you do need more they adjust upward to give you more. The problem with this is that they constantly reacting. You need to have OA events to prompt the machine to give you more pressure.

I have come to the conclusion for basic apnea a fixed pressure machine is better. It does not need event prompts to give you the right pressure. If you have done your homework you start each night with the right pressure. For someone that gets into treating apnea with a home test and no titration test for pressure an auto machine is a good idea if you monitor the results with OSCAR. It will tell you what the right fixed pressure is, and then you can switch the machine to fixed CPAP mode.

An ASV machine is very different. It tracks your breathing breath by breath and corrects each one. It is much more sophisticated and in some cases can be the only good solution for central apnea that can't be addressed by minimizing pressure.

Just my thoughts.

Here is an example of a OA event in the middle of quite nice smooth sleep at 6:39. It starts a cycle and 5 minutes later at 6:44 there is a CA event. They are not unrelated. The OA caused the CA. But the fact that that the OA caused the cycle is an underlying issue. My O2/CO2 regulation is not that stable.

You may, or may not have similar issues. But that is the level of detail that you need to look at to figure out what is going on. In the short clip you posted I did not see that issue, but you have to look at each one to see what is going on.

What I normally do when I see this is to drill down to look at each of the CA events to try and figure out what may be initiating them. I like to display Minute Ventilation along with the Flow Rate graph to see if the breathing depth is cycling. I find in some case I have a disturbance of some kind, like a obstructive event or partial one that starts the cycle, and then at the minimum of the cycle I get a CA event, which then may repeat.

Unless this is a regular occurrence I would not worry much about it. If it is happening all the time then the first thing I would try is to reduce the pressure until I start to see some OA events. In general I try to use the lowest pressure possible without causing many OA events.

Here is a better look at this CSR graph.

You may also want to consult a cardiologist about the CSR. From the numbers you post, it does not look like you are going to resolve the CSR and CA event frequency with just lower pressure. You may also want to discuss the use of an ASV instead of a CPAP if cleared to do so by the cardiologist. This document discusses the screening process to consider the use of an ASV.

ResMed ASV Therapy

You may have figured it out but if you click repeatedly on a green area highlighting CSR you can bring up the expanded detail on your breathing response to compare it to what you see in this document. My long term CSR is 0.02%, so I see it occasionally but not very often. Here is an example of what I see when I zoom in. Minute Ventilation cycling is another indicator of CSR. In the worst cases you can get a CA event between every CSR cycle. That racks up CA events pretty rapidly...