Will an ASV machine help eliminate my CSA/CSR clusters ?

[barney999]

Hi all. 

I've been a member for awhile, but this is my first post. 

As background, I'm a 73 year old non-obese, active male. I was diagnosed with Severe Sleep Apnea (31) via a Home Test, more than 2 1/2 years ago. I was then prescribed a ResMed AirSense 10 Autoset and have used it nightly since then. During this time, I've pretty much been on my own in terms of maximizing its effectiveness thru research and trial-and-error. 

I very, very rarely have any OSA, however, I have a cluster of CSA/CSR on a fairly regular basis. I wonder if an ASV machine would help alleviate this problem.

Attached is a recent night that is representative of the CSA/CSR I regularly experience.

I didn't include Leak Rate nor Snore, because there's no leaks (thanks Bleep) nor snoring, which is the norm for me.

Thanks very much for your help.

[Sleeprider]

Your periods of CSR appear in a classic flow oscillation consistent with what we would identify as Cheyne-Stokes, however the period of time is relatively brief and your AHI on the whole is not currently going to prompt a physician to prescribe ASV without significant comorbid conditions. This pattern is caused by changes in respiratory drive in a sort of feedback loop related to the alternating hypercapnea/hypocapnea and associated hypoventilation/hyperventilation. ASV does specifically target CSR and uses pressure support to counter hypoventilation and lack of pressure support during hyperventilation so the pattern just never gets established. You could eliminate these symptoms with ASV, however you should verify you have good heart function with normal to not less than 45% left ventricular ejection fraction, to safely use it. Unless this becomes more prevalent, it will be challenging to persuade Medicare to pick up the tab.

[barney999]

Thanks very much for the information and assessment. It's much appreciated.

If an ASV machine will help improve my sleep health, I'll accept the out-of-pocket expense of the machine as a long-term (hopefully) investment in my health.

Concerning the left ventricular ejection fraction, I recently went thru routine cardiac tests. At the time, I mentioned to my cardiologist that I was looking into an ASV machine. After the tests, she followed up and let me know that my LVEF is 70% and that there is no cardiac contraindication to the ASV machine. This was good to hear.

A couple of questions. 

Will an ASV machine run at the same relatively low pressure settings as my APAP machine, which is set at 6.4-12? Most nights I rarely get a max pressure much above 8, which in general works very well for me. I have issues with higher pressures. 

Outside of expense, is there any reason why I would not want to switch to an ASV machine? Is there a downside?

I'm also trying to understand from a user's perspective, what I might expect if I switch to an ASV machine, so any feedback regarding this will be much appreciated.

Next week, I'll be seeing a new sleep doctor, who I've heard positive things about. I feel that I'll be much better informed about ASV when I see her thanks to this support group.

Thanks again.

[Sleeprider]

ASV can effectively operate at low EPAP pressure, and will use its algorithm to increase pressure support on a breath by breath basis. You are currently using CPAP with an EPR function that works like bilevel pressure support with up to 3-cm pressure difference between IPAP and EPAP. Your EPAP pressure starts at 4.0 IPAP at 6.0 or 7.0 depending on your settings. This pressure support is fixed. With ASV, we would likely retain that low EPAP, but would set the pressure support to allow between 2.0 (like your current CPAP) and 7 or 8 cm maximum PS. This could give you a pressure span between 6/4 and 12/4, and we would judge the effectiveness of that at stopping periodic CSR and centrals. For many individuals a maximum PS of 8.0 cm over EPAP is often effective. Default titration settings would be up to 15 cm PS. We don't have to go there if you respond to the lower pressure support. We often find the stimulus of pressure support is enough to trigger spontaneous breathing. So we don't necessarily need the machine to be a "ventilator", as much as a reminder to breathe. If you need more PS, it is there. The objective is to get good respiratory compliance while minimizing the sleep disruption that a ventilator can cause. There is a LOT of experience on this forum you can call on. Whether you end up feeling better rested is something no one can answer up-front. The machine is designed to stand-down until you need it, then it can feel very assuring, or sometimes like it is taking over. There is a period of getting used to how the machine works and optimizing the settings to match your needs.

[barney999]

Thanks Sleeprider! I greatly appreciate your input!

I hope some ASV users chime in here with their experience, but in the meantime, I'll be reviewing past ASV threads.

Thanks again.

[barney999]

Does anyone have a suggestion on how I can better search the forum for information on ASV machines including user's experiences?

The forum doesn't allow for a 3 letter search, such as ASV, and I haven't come up with a good search tag. So far, my crude method is to just go thru the list of most recent posts looking for ASV in the subject line.

I've found a few threads with very helpful information and was actually going to provide the link to one as an excellent ASV resource, but I wasn't allowed to post the link since I have less than 4 posts. :-(

[barney999]

One more piece of information related to this.

On 4/18/2022, I had a Sleep Lab study done with me sleeping in a supine position. The machine used for the study was BiPAP.  

From the study,

"During the treatment study, the patient had a total of 36 respiratory event(s) for an AHI of 15.3. There were 0 obstructive apnea(s), 0 mixed apnea(s), 19 central apnea(s), and 17 hypopnea(s)."

This is consistent with my OSCAR data during those periods of time when I sleep on my back. 

Fortunately, I'm able to keep my AHI low by sleeping the vast majority of the time on my left side. However, there are numerous reasons why I can't always do this and need to sleep on my back. The downside of sleeping on my back is CSA/CSR, which affects the quality of my sleep with headaches, dizziness and brain fog.

[Sleeprider]

The ASV will always provide pressure support to cause or stimulate a breath when your breath rate or volume target is not met, so of course it will work to eliminate the events you have described.

[barney999]

I saw my new Sleep doctor today. Her background is in Internal Medicine, although she's been a full-time sleep specialist for a number of years. I was impressed with her. She listened and asked good questions that showed me she understands my sleep issues, rather then just basing my sleep health strictly on the AHI index, as other sleep doctors I've seen have. She's not opposed to an ASV machine, but she wants to see if she can determine what might be causing my CSA/CSR events. 

Towards this end, she recommended that I have another in-lab sleep study, this time at the most respected hospital in my area, which is the only sleep lab in the area that she recommends. She proposed that I have a 2-stage in-lab sleep study with the first stage being without a machine sleeping in a supine position, which is the sleeping position I'm in when I have CSA/CSR events when using APAP. The second stage would be with a machine with possible oxygen supplementation, depending on how things go during the first and second stages. She wants to see the nature of my apnea without a machine and also whether or not my CSA/CSR is machine induced. She made a lot of sense to me, but then again, I'm a novice in this area.

Although I don't have any problem falling asleep, she also recommended that I look into CBT-I for a problem I have with awakening after 4 or 5 continuous hours of sleep and then being unable to fall asleep again. Interestingly, before APAP, if I awakened after 4 or 5 hours of sleep, I had no problem falling back to sleep. One of her CBT-I recommendations is a Cleveland Clinic 6-week, on-line course for $40 that I'm thinking of taking. I'll admit I'm skeptical, but I'll try my best to give it a fair shot with an open mind.