New to CPAP... do I need an ASV?

[DBestman]

Hello CpapTalkers,
Help! I need your expert advice!

This is my first post, but I've been reading and learning on this site for about a month. I am a male of 42 from Canada. I've been feeling tired for a few years and asked my doctor to have a sleep study done to detect sleep apnea.
So a month ago, I had an in-lab sleep study & titration done in the same night. The results: moderate obstructive sleep apnea with an AHI of 20.3. On my back, the apneas are worse: AHI=53.2 while it's 10.2 in the other positions.
I think the titration portion of the study lasted 3 hours max. The sleep tech told me that she wasn't quite satisfied because I didn't get into REM sleep during the titration. She also told me that I had central apneas, probably induced by the CPAP. The titration achieved an "adequate" AHI of 5.5 at a pressure of 6 cmH20.

So I was prescribed a CPAP machine with a fixed pressure of 6 cmH20, and I've been sleeping on that pressure for 2 weeks today. But instead of feeling better, I'm feeling worse and worse after every night. I am 100% compliant and keep the mask all night. I find that my mask, a DreamWear, is rather comfortable and I got accustomed to it pretty quickly. I do have some mouth leaks from time to time though. It's better since I raised the humidity, but still have some.

But since I'm now feeling a lot more tired and sleepy than before, I'm getting discouraged. For the 2 weeks I have an average AHI of 8.35 (CAI=5.01, HI=2.33, OI=0.94). My stats for the 2nd week are a bit better: AHI=7.33, CAI=4.36, HI=2.32, OI=0.56. I tried with and without EPR but didn't see a marked difference.

One night, to try to reduce the mouth leaks, I slept with a soft cervical collar. Although it was really uncomfortable, I had no mouth leaks. But I also got my sole AHI below 5: AHI=2.81, CAI=1.87, HI=0.82, OI=0.12. I didn't try another night because I didn't want to skew the numbers monitored by the sleep tech.

So my obstructive apneas are treated well with the CPAP, but the central apneas seem to be killing me. When I'm falling asleep, I can feel that I stop breathing or pause for some time and when that occurs, the machine gives quick pulses of pressure that wake me up a few times before I fall asleep.

I contacted my sleep tech today, and he will send a report to my doctor. He said that my AHI was "tolerable, being around 10", and we'll see what my doc says. Ugh!

If I understand correctly, my Resmed Airsense 10 Autoset machine does not treat centrals. So do I need an ASV machine? Do I have enough centrals to justify it? Or will my centrals simply subside with time if I have enough patience and live to that point?

I certainly don't feel like my AHI is tolerable, so I'd appreciate your help/opinions, because I'm getting really discouraged and I'd like to have an idea of what possibilities are out there for me. Another titration study maybe? I guess I'd also like to know if I should be prepared to insist on getting an ASV if I need to.

I take some medications: Atacand and Norvasc for my high blood pressure and an antidepressant (Effexor).

I have installed SleepyHead and tried to understand what I see. I don't know exactly what to show you guys that would be helpful, but here are some snapshots from a typical night:









Thanks for your help! I'm proud of being part of such a great community.

[Julie]

bump

[Pugsy]

Are you waking often during the night or are you sleeping soundly for the most part?

The centrals might fade away on their own with some time but it usually takes a few months...and that's if they fade away.

You are probably borderline needing ASV with the Central index 5 or higher if it happened all the time but you had one night where it was less...so it can get there.
Doctors normally will take a wait and see attitude when the centrals are in the number you are having because they could fade away.

Do you have a follow up appointment yet? I think it would be a good idea to at least have that appointment and share your concerns with your doctor.

[DBestman]

Thanks for the kind reply, Pugsy.

I am aware that I wake up a few times during the night, very briefly. Maybe 4-5 times? I may wake up more often when I have mouth leaks. Since my mouth leaks don't seem to disappear completely, I'll purchase a chin strap and see if that helps.

Oh boy, I'm not sure if I have the energy to wait a few months to see the centrals disappear... I don't have an appointment scheduled with my doctor (it's a general practitioner, not a sleep doctor) but I will ask for one, depending on her response to the sleep report.

Are there disadvantages (other than the price) of an ASV compared to a CPAP?
Oh, another question. Do you think my hypopneas are central in nature? Should that be considered in the decision making?

[Pugsy]

The only potential disadvantage (other than price) to using ASV might be if you have existing heart problems...specifically congestive heart failure where the ejection rate is below a certain number. It's a significant disadvantage though. Last year it was determined that patients in congestive heart failure with ejection rates below 45 (I think) have an increased mortality risk. Meaning a few more of those type of patients on ASV died than those not on ASV. It's not something that has had a chance to have a lot of research on and they don't know why ASV might increase that risk or if the ASV really makes the problem worse. Patients who have congestive heart failure with low ejection rates are already really sick with an already increased risk for death simply from the CHF. At any rate while they are still study things they are advising patients who have CHF with ejection rates below a certain number not use ASV.

Now if your heart is normal and healthy and you are in otherwise general good health then there's no real disadvantage other than the cost and it takes a bit of getting use to. Also if a person can't get the doctor on board so that insurance will be on board...you have to find a machine from the secondary market and they are expensive but they can be found. I am using ASV for other reasons and I had to get mine from the secondary market.
Good deals are out there. You are in Canada. I think that you could probably get an ASV machine from secondwindcpap.com without a prescription and while their prices aren't cheap...they are fair and when we don't have official prescriptions...we have to find other sources.
Now I do know a forum member who can be trusted that sometimes has ASV machines available...so if you want to chat about that...send me a private message.

Now sometimes a regular bilevel machine can be used when it's higher pressures causing the centrals but your pressure is really quite low so I don't know how much a regular (non ASV) bilevel machine would help.
You could maybe do a little tweaking with your current machine to make it sort of mimic regular bilevel to see if it helps or not. I see right now that your EPR is off. When EPR is on and set to 3 then you would effectively be getting regular bilevel pressures. It might be worth trying.

Are those hyponeas central in nature? Don't know...wouldn't be impossible though but normally the FOT used with ResMed machines to determine if the airway is open or closed (or in the case of hyponeas probably partially closed) is fairly accurate. Hyponeas are normally obstructive in nature but it wouldn't be impossible for them to be central in nature. Unfortunately knowing for sure is really hard to figure out with the data available from our machines unless someone really knows how to evaluate the individual breaths (like a sleep lab tech). I am not that good at evaluating individual breaths unless the changes are pretty blatant...like sometimes seeing awake breathing getting flagged by mistake. If it's obvious then I can sometimes spot it but I am not good at evaluating breaths when the changes are extremely subtle.

Since you report at least 4 or 5 awakenings during that night that you remember there's probably a few more that you don't remember....it's possible that some of what you are seeing getting flagged as central/clear airway is just awake/semi awake SWJ sleep/wake/junk. SWJ doesn't count and we have to mentally remove it from AHI evaluation.

It's interesting that you had your "best" night when using a cervical collar. It probably kept the chin up and kept the airway open from neck positioning. Your hyponeas decreased too...which makes me think that they are more obstructive than central. If they were central then neck position or chin supported wouldn't/shouldn't make any difference.

A central index of 5 or 6 even if they were all real centrals and no SWJ is barely diagnostic for central apnea.
It's not like you are seeing 8 to 10 central average every night.

So that brings us to your complaint of feeling worse on CPAP and while we might not expect to feel immediate improvement, we sure don't expect to feel worse. If you weren't feeling worse then maybe there wouldn't be such an urgent feeling to "do something" to improve things. I feel your pain...I would probably feel the same way and be sorely tempted to get my hands on an ASV because patience is something that I don't have an abundance of myself.

I think I would investigate the cervical collar use a little more just to see if that one night was a fluke or not.

I have heard from other Canadians that their docs are using AHI of 10 as a guideline and if that ends up being the case with your medical care team then it's highly unlikely that you are going to be able to get your doc on board for ASV trial. It's worth trying though so that your insurance will pay for ASV should it be determined that it's worth trying or is actually needed.

Now if you would sleep better at least trying ASV (even if on your own) and you don't have congestive heart issues....it can be done. It's not an ideal situation and takes some trial and error to figure out the optimal settings to address the obstructive stuff as well as the centrals but it can be done.
If you elect to go the DIY route...I would suggest that you look at the ResMed ASV models...either one like I use (S9 Adapt) or the newer AirCurve 10 ASV because there's less settings needing adjusting than the Respironics ASV machines have. I have used both brands in the ASV model and I think that ResMed way of doing things with their ASV is more set it and forget it and let the machine decide what it wants to do.

So there you have it....you are maybe borderline for needing ASV. It's a real expensive experiment to go at on your own though but it can be done...it's not ideal of course but not impossible. Ideal would be having the doctor on board but sometimes we don't get the luxury of "ideal".

It's not my job to tell you what to do but instead I think that my job is to explain your options and any pro and cons so that you can make an informed choice about what you want to do. Your situation isn't as clear cut in terms of real need for ASV as I have seen in others.

As long as your heart is healthy...if you want to go the DIY route it can be done. I would feel better if you at least tried to get your medical care team involved but if you want to go the DIY route and are willing to pay the $$ for the machine so that you know that you have tried everything...we will still be here for you and try to help. Finally...should you elect to get ASV on your own...it can be dumbed down so to speak to work like a regular cpap or bilevel or whatever but it is an expensive dumbed down machine should it be determined that you don't need ASV.

[DBestman]

Wow, thanks for all that information. This gives me lots to think about. I will see what my doc thinks of my situation. I'll schedule an appointment next week.

No I don't have congestive heart failure, so that's OK.

I did try using the EPR at 3. Actually that's where I started at, but there's no real difference I could see.

Yes I find it really bizarre that I'm feeling so much worse since I'm on CPAP, especially since I'm having way less apneas than before it. Is this a common complaint? I don't think I'm waking up more often than before. My wife even tells me that my sleep is much less agitated.

I just realized that I started taking a new pill a day before starting CPAP: Norvasc. So I called my pharmacist and he said it could cause fatigue for a small percentage of people, though not that much fatigue. I will try to stop taking these meds for a week and see if things get better.


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[DBestman]

So I stopped taking my Norvasc meds, and started feeling better the very next day!
Now I'm just "normal" tired, instead of brain-dead zombie tired. Also, my AHI numbers are going down, so the CPAP may be the correct therapy for me once the centrals subside. So the "wait and see" approach seems like the correct one after all .

[Arlene1963]

I'm just bumping this thread back up because I found some research regarding Calcium Channel Blockers (Norvasc is a CCB) and sleep efficiency in OSA patients that could explain some of the fatigue the OP was experiencing.

http://www.ncbi.nlm.nih.gov/pubmed/21546880

Also, Norvasc often causes leg edema (one of the most frequent side effects, in fact).

There has been some interesting research that at night rostral fluid shift (associated with leg edema) contributes to OSA.

Here's a study from 2014 dealing with this issue: http://jtd.amegroups.com/article/view/3466/html

Does make one wonder how many of the drugs we are prescribed actually contribute to making sleep and OSA worse?

[DBestman]

Thank you Arlene for the study links.