Follow-up to "First dysfunctional nights with VPAP"

[lostsheep]

Hi, I would like to share some data from my S9 auto-VPAP. I was interested to see how the pressure would titrate in Auto-BiPAP mode, and got a bit of a surprise the first night:



Here is what it looks like when zoomed in a bit - I guess you could call it periodic centrals:



The last few nights I've been limiting the pressure to IPAP 8 / EPAP 4. Although it reduces the CA's, my breathing pattern is often periodic.

Last night I put the VPAP in "S mode" with "Easy Breath", and it felt great... but the breathing looks periodic again:



Strange that this seems to get worse through the night.

I'm trying to get the treatment pressure up, since that seems to be my best hope for reducing daytime fatigue. I have been using CPAP at a prescribed pressure of 7 for the past 6 months, with little relief. My AHI with CPAP was about 2, and mostly CA's. Other than that, with CPAP the flow rate waveforms would often appear jagged and flattened.

Has anyone else seen this when first using BiPAP, or when attempting to increase pressure? Any suggestions would be greatly appreciated

[Xney]

You need to see if it goes away, but it kind of looks like CSR or PB.

Which, if true, says you may need an ASV, not a VPAP.

Can you blow up a range of like 2-3 of those funky breathing patterns into a graph? Like zoom in a bit.

[lostsheep]

Hi Xney - Oh dear, you were up late. I hope that does not mean you are having troubles with your own therapy

As requested, here is the greater-resolution image from Sept 25, my night on auto-titration pressure:



But something very odd happened last night - the breathing oscillations & CA's were greatly reduced. All of the machine settings are the same as Oct 1 (shown in my first post), so maybe my body is settling down a bit? I'll give it another few nights like this.

Here is last night - it looks like normal dream phases (for me on XPAP, anyway), and most of those CA's are when I was actually half-awake:



I'm hopeful - it seemed like a good sleep, and I feel halfway decent this morning

[lostsheep]

A forum member inquired as to my status, so here's an updated summary of my experience so far (with some repeat of previous posts):

I've now been on the VPAP for about 5 weeks. Before the VPAP I used a CPAP, mostly set at 7 inH2O. After 6 months on CPAP I wasn't feeling energetic at all, and I could see that my breathing waveforms often looked a bit flattened or jagged. From Dr. Krakow (web info) I learned that this might indicate sub-optimal therapy. My hope with trying VPAP was that I could go to a higher pressure, and get more therapeutic benefit.

Looking back at my original lab titration, there was a mention of centrals showing up with increased pressure. I think that is why it was prescribed only 7 inH2O. But I wanted to see if I could adapt to more pressure with some time on VPAP.

The first night, with VPAP on auto mode, I saw pressure go up to something like 10 or 12, with lots of periodic breathing and a huge incidence of centrals (shown in previous post). I felt terrible the next day. I then set the pressure to constant 8/4, and have left it there ever since. About a week into this, I discovered that I really like the "easy breath" setting. I'm reasonably comfy with my current mask so it feels OK when I go to sleep - well, enough that I don't lie awake if I'm tired. Should be all good, right?

In the morning I typically see AHI's from 3-6, almost all CA's, and I've noticed there is a relationship between the AHI and and how I feel in the AM - and pretty much all day. But I never really feel right. I also notice a dull headache some mornings. Typically I am slow to wake (which is NOT me), and don't feel like I am well rested - sort of mentally foggy, sometimes bad enough that I want to nap. I have no physical stamina now - I get tired from just a few hours of normal exertion.

When I look at the data now there is still some periodic breathing, but I'd say most of the night it looks fairly regular. Also, when looking at CA events I notice that oftentimes, a few breaths before the breathing pause (flagged as a central), my breathing rate transitions to resemble the wake-state. So maybe something is going wrong to disturb my sleep - or it could just be part of the periodic breathing thing. Of course I don't remember any of this.

I wonder if I'm having an issue with pressure therapy in general, perhaps CO2 overload (hypercapnia). This has been vaguely suggested by both an RT and sleep doctor.

Recently I tried sleeping without the VPAP for comparison - first time in 7 months. (I'm staying on my side, as I know I can get at least some REM sleep this way. I'm not too worried about big desats - my main issue w/o XPAP seems to be poor sleep architecture.) I only did it for one night, but it seems I did wake up more alert (and no gas that day ). No, I haven't decided to sack the VPAP over the long term, but I am becoming skeptical. It seems this therapy solves one problem while causing another.

I was offered a trial period with ASV, but that seems even more imposing for my brain/body.

I've decided to get a second opinion, which probably involves a follow-up sleep study & titration. I made an appointment with a research hospital (National Jewish) in Denver, as I'm told they are quite capable and have the respiratory expertise to figure out therapy issues. Even though I have a sleep doctor that I like, I am initiating the next step.

[Xney]

It could be Complex Sleep Apnea, which is where when xPAP therapy is applied, Obstructive Events go away, but you start having Central Events. It's less common than purely OSA, but it's treatable with ASVs.

I would really follow up with your doctor about it, maybe try an ASV.

[archangle]

Keep in mind that even when you are in "problem" mode, you're still not completely stopping breathing for that long a period of time. And that you're still getting a fairly good minute vent rate.

Keep working at it with your doctors, but don't panic too much over the numbers.

[n0hardmask]

It could be Complex Sleep Apnea, which is where when xPAP therapy is applied, Obstructive Events go away, but you start having Central Events. It's less common than purely OSA, but it's treatable with ASVs.
I would really follow up with your doctor about it, maybe try an ASV.

I'd like to chime in with my limited experience on starting on biPAP. When I started on the VPAP, I, too experienced huge numbers of centrals (see post viewtopic/t82714/viewtopic.php?f=1&t=83 ... 91#p758591) After a few days, it has settled down to a more civilized number of Centrals. I need to post my latest, but just got back from a week out of town - I used my S8 APAP for travel.
But I wanted to toss out the two thoughts that transition can be surprising, and Xney may be on-target about the Complex SA.. been suspecting that myself. Good luck with your learning process.

[Todzo]

I wonder if I'm having an issue with pressure therapy in general, perhaps CO2 overload (hypercapnia). This has been vaguely suggested by both an RT and sleep doctor.

Hi lostsheep!

While it is possible that hypercapnia is part of your issues (part of the time?) I think that while on PAP hypocapnia is more likely. I say that because PAP induced centrals are exclusively hypocapnic central apneas. Apparently the body is searching for eucapnia but is not finding it well.

Trauma from an assault and robbery in 2005 has made me much more aware of this issue. The memories flooding back near the time of the anniversary of the attack tends to destabilize my breathing. I would often wake up breathing very hard, feeling like someone beat up my nose, and with a very dry mouth. After quieting my breathing for a few minutes all went back to normal (including the crazy out of place air hunger!).

Working with my doctor one year I actually used this to get through the time: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3014237/ . Also at that time I began to use pulse oximeter guided breathing (a eucapnic breathing re-training technique) to learn how to breath more properly all the time.

As a result my CPAP pressure needs dropped from 15 cm/H2O to 8 cm/H2O! Also, my continuing attempts to loose weight (diet and exercise going back decades but concentrated the last decade) really started yielding fruit. Belt went from 44 to 39.

I started with a Personal Trainer at my fitness club today. I got a great surprise. She is a PhD level Exercise Physiologist who often deals with people at extreme altitude. Since extreme altitude and breathing stability are greatly associated I finally had someone I could talk with about breathing stability. She is well aware of this issue as it applies to PAP treatment.

For her work she has found the pulse oximeter to be the best tool to determine if breathing is eucapnic or has wandered into the hypocapnic zone. What I find is that a reading higher than 97% means I am breathing too much. If you think about it total saturation means that no blood oxygen is being used. If CO2 becomes lacking circulation and oxygen transport become frustrated and so there is a higher O2 saturation level. When I mentioned that I seem to find the lowest heart rates at my computer at a blood oxygen saturation reading of 95% she mentioned that I might well be actually a bit more eucapnic at a blood oxygen saturation reading of 94% in that situation (sitting quietly at my computer). Perhaps I will see that as she gets me in better shape.

Have a great week!

Todzo

[Xney]

Yes, you have to wait a while to see if centrals go away when starting VPAP (or CPAP/APAP for that matter), as n0hard says. If they're still present at the same rate after say a month or two, then that's when you have to really think about complex sleep apnea.

[The Sheikh]

"But something very odd happened last night - the breathing oscillations & CA's were greatly reduced. All of the machine settings are the same as Oct 1 (shown in my first post), so maybe my body is settling down a bit? "


Yes, could be your body settling down. For me, most centrals occur as I fall asleep. If I wake up four times during the night, I have four central minefields to pass through. This can wreak havoc on sleep without an ASV machine.

But what may be happening for many CPAP-only people is the first few nights of new therapy they are restless and wake up a lot from the strange pressures. This creates the potential to have these "transisional" centrals more often than normal. Once the body settles down for a few nights, the wake-ups are less and maybe the centrals become few. All depends on the person.

So, if you are seeing a big centrals improvement, keep this in mind. But if they get worse using CPAP, then an ASV machine is another option if needed.

Tom

[lostsheep]

An update...

After about 10 weeks on the S9 VPAP I did not improve, either in data or subjective results. Last week I was titrated for ASV. As of last night I started new therapy at home with an S9 VPAP Adapt. This morning my AHI was zero(!), so even though the breathing waveforms look a bit funky at times, this machine took care of outward events. But I've felt pretty wiped out all day. I hope it gets better.

Thanks for all the input on my last post. I did read them, and don't mean to be ungrateful. Sometimes I get overwhelmed, frustrated, and stop posting on the forum because I just generally feel crappy.