New to ASV, new to SleepyHead

[tmoody]

During that period of shallow breathing your machine is pumping out maximum PS, with IPAP reaching 25 on every breath. But it's getting very little response in terms of air flow. You say this was a one-off, but if it happens again I'd be concerned enough to see the doc tout suite. Do you recall anything unusual from that time - sleeping on your stomach perhaps, or the hose getting tangled up?

I've looked through all the data I have and I haven't spotted anything else remotely like that one. I don't remember anything unusual about that night. I might have rolled onto my back for a while; that's never good. As for the hose...this setup has a short length of narrower hose that connects to the main hose. I don't know if it gets tangled up but I do know that I seem to end up with my head/neck on top of it much more than I did before, with just the larger hose.

Meanwhile, last night was a bit of a setback, with 9 centrals, after seeing none or at most one since starting ASV. This is my second night with PSmin raised to 2.



Interestingly, SH reports no large leaks, but Dreammapper reports Mask Fit of only 90%, with "large leak time" of 0:51 hours. Looking at the leak rate graph, there's only a weak correlation with the centrals. I don't know how to reconcile what Dreammapper and SH say about leaks, but I do get the idea that I'm getting more leaks since starting with this barley hull pillow. I may go back to a normal pillow tonight and see what happens.

I'll leave my settings alone for a few more days. Last night seems like an anomaly.

One other factor: I've been really trying to drop some more weight, so I decided to revisit the 5:2 fasting plan, that I had some success with in the past. So yesterday was my first fasting day--no food since Sunday dinner, just non-caloric fluids. This morning my BP was elevated. It's possible that my cortisol was sky-high during the night, and that was causing the centrals, as well as the BP. I've read (this morning) that I'm not alone in getting elevated BP from fasting, so I may have to end that experiment and try something else.

[richb]

You might need a nasal mask instead of the pillows. I use the ResMed Mirage FX with pretty good control of leaks. I do have issues with the mask occasionally blocking a nostril or being bumped by my pillow and leaking. Leaks are a big issue when pressures go high. A thought on that period of shallow breathing: If your nose was clogged up for some reason you would not be getting much air delivered via the nasal pillows. Pressure would go high and respiration would appear to be shallow. I have already had nasal surgery trying to deal with such issues.

Rich

[tmoody]

You might need a nasal mask instead of the pillows. I use the ResMed Mirage FX with pretty good control of leaks. I do have issues with the mask occasionally blocking a nostril or being bumped by my pillow and leaking. Leaks are a big issue when pressures go high. A thought on that period of shallow breathing: If your nose was clogged up for some reason you would not be getting much air delivered via the nasal pillows. Pressure would go high and respiration would appear to be shallow. I have already had nasal surgery trying to deal with such issues.

I have a nasal mask left over from CPAP. In fact, looking at pictures online, it may well be the ResMed Mirage FX. I used that for almost ten years. So I can experiment with that if the leaks continue.

On the subject of leaks, given that Dreammapper and SH seem to have different ideas about leaks, can you offer any advice about how to use SH leak data? I do have data from my DreamStation four-month adventure, during which time I used the nasal mask. Looking at it now, the numbers were pretty consistently lower than what I'm seeing with the pillows.

On ASV, with Swift FX pillows, my average total leaks each night ("including natural mask leakages", as SH puts it), tends to be 40+. On APAP, with the nasal mask, it was around 25. So I guess that tells a story.

Edit: I like the look of the Swift nano, without the hard plastic frame, and it looks like I can fit it on the same headgear I already have.

[JSL747]

It looks to me that the Obstructive event was about 30 seconds long. There is a resumption of breathing at about 1:55.10.

I guess I'm reading it wrong. Apparently the OA is followed by a lengthy period of very shallow breathing, lasting several minutes.

During that period of shallow breathing your machine is pumping out maximum PS, with IPAP reaching 25 on every breath. But it's getting very little response in terms of air flow. You say this was a one-off, but if it happens again I'd be concerned enough to see the doc tout suite. Do you recall anything unusual from that time - sleeping on your stomach perhaps, or the hose getting tangled up?

Hi toomdy, your thread is a great read...I am following...

DeepBreathing, richb, vsheline, hi guys, I don't usually "play with the Big Boys," or in the ASV threads, but I would like to commit:

I had 120sec OAs about once a week with a AHI of 1.5 (the real thing--it was checked out). It was due to my neck failing foward cutting of my airway. Now I use a soft cervical collar and my OAI is zero 9 out of 10 nights and none over 18 sec.

Just something to think about if it keeps happening and you can't find any other cause

[tmoody]

I had 120sec OAs about once a week with a AHI of 1.5 (the real thing--it was checked out). It was due to my neck failing foward cutting of my airway. Now I use a soft cervical collar and my OAI is zero 9 out of 10 nights and none over 18 sec.

Just something to think about if it keeps happening and you can't find any other cause

That's an interesting occurrence. I wonder if that one occurrence had something to do with neck position. It's possible. I've yet to find a really good pillow.

Continuing my ASV diary... Last night's AHI was 2.6, so that's a step in the right direction from the previous five nights. On the other hand, I had three centrals, which is better than the previous night's 9, but not as good as zero, which is what I'd been seeing most of the time on ASV.

At least one of the centrals, and very likely two of them, were before I fell asleep. In fact, the third one was also not long after I got up to go to the bathroom. If I was asleep, it was just barely. So the three centrals were during a state of being awake or in light sleep.



Another thing I notice about last night is that the period just before waking up, at about 2:40, shows a spike in both mask pressure and leak rate. So whatever was going on at that time is probably what woke me up. Then, when I returned to bed, there was a cluster of hypos just before the central.

Now that I think of it, my machine is set to a 20 min ramp. It looks like all three centrals occurred during ramp time.

The only other significant thing is last night I went back to my old pillow. I had fewer leaks, but still more than I did on APAP. When the Swift FX nano arrives in a few days, I'll report on that.

My settings haven't changed. Still PSmin=2, and I haven't bumped EPAPmin yet. That'll be my next adjustment after I see how things go for a while longer.

[richb]

At least one of the centrals, and very likely two of them, were before I fell asleep. In fact, the

Now that I think of it, my machine is set to a 20 min ramp. It looks like all three centrals occurred during ramp time.

I turned off "ramp" on my machine. The machine doesn't respond to Centrals and Hypopneas during ramp. Try cutting the ramp time down in 5 minute pieces over a few nights. You should see a big improvement in your AHI.

Rich

[tmoody]

Good morning, world.

My AHI was 5.2 last night, all hypos except for one central which occurred during ramp, which I shortened to 10 minutes. Dreammapper reported 98% mask fit, with .08 hours large leak time (1.7% of the night in large leak). SH reported no large leak but showed an average leak rate of 8.10 L/min, which is above my April average (6.3). So...more hypos than average, otherwise unremarkable in terms of recent patterns.

I'm going to try bumping EPAPmin from 8 to 9 tonight, to see what that does to the hypos, if anything. I've kept it at the current settings (PSmin=1, EPAPmin=8) for the better part of a week without noticing any substantive change from the numbers I was getting with the setup it was delivered with.

I woke up feeling pretty well rested, and didn't get up at all during the night. Subjectively, I expected a lower AHI than what I got, which shows how accurate my subjective impressions are.

[tmoody]

Good morning, Apneaboardistas.
I made the mistake of changing two variables last night. One was switching from Swift FX nasal pillows to Swift Nano nasal mask. The other was raising my EPAPmin from 8 to 9.

The result this morning was...AHI 4.5, which is less than it was the previous night, but I had five CAs and two OAs in the mix. One of the OAs was pretty long, as you can see:



So, even though the AHI is lower than the previous night, the whole point of ASV therapy is to get rid of centrals, and there shouldn't be a lot of OAs either. Two OAs isn't a lot, but still...

There were no large leaks, but the overall leak rate was about the same as what I was seeing with the nasal pillows.

So, my question is: Could raising EPAPmin have somehow caused the deterioration in CAs and OAs? Or is one night possibly just an adjustment period?

[DeepBreathing]

Gday Todd

I think one or two (or even five) apneas over the course of a night is no big concern. I know you're trying to target zero apneas but that's not realistic in the real world. I am concerned about those really long obstructive apneas you're getting, even if they are isolated, and you might want to raise those with your doctor.

I come back to our original discussion - pressure support treats central apneas and EPAP treats obstructive events (hypopneas and obstructive apneas). However this needs to be nuanced considerably more than my limited knowledge allows. I have read an excellent paper by Javaheri, Brown & Randerath which goes into great deal of detail about how the algorithms of the Resmed, Philips and Weinneman machines work. I was interested to note that on the Philips, if hypopneas are detected it raises PS first followed by EPAP if there is no response to the PS increase. (Which I think is more or less what palerider said). On the other hand, the same machines do a "proactive search" to determine optimum pressures and will raise EPAP in response to hypopneas. The paper can be found here: http://journal.publications.chestnet.org...id=1891790

Could raising EPAPmin have somehow caused the deterioration in CAs and OAs?

I doubt it. Raising EPAP will reduce the number of obstructive events including obstructive apneas - I don't think there is any way it will make obstructives worse. On conventional machines raising pressure can certainly induce central apneas but ASV machines work quite differently (as explained in the paper I referenced). I don't think that raising EPAP will increase the number of centrals on an ASV.

At this stage I would offer the following advice (bearing in mind I'm an engineer not a medic):

1. Check your settings to ensure you're in the auto EPAP mode (however that is described in Philips-speak). It looks like your EPAP is fixed on 9 and not varying. Otherwise don't make any further changes for at least a week
2. Do not review your data every day - this can become an obsession which detracts from the real purpose of the therapy which is to get refreshing sleep
3. Do keep a sleep diary where each morning you note how you feel, what sort of night you had and whether you can make it through the day without excessive sleepiness.
4. Only review your data after a week, and look for overall trends, and correlations with your sleep diary.
5. Do something about those long obstructive events. Talk to your doctor, maybe consider whether you might have a positional problem (eg head flopping forward onto your chest) which could be exacerbating the obstruction.

Hope this helps

[tmoody]

Gday Todd

I think one or two (or even five) apneas over the course of a night is no big concern. I know you're trying to target zero apneas but that's not realistic in the real world.

I agree, and I have to remind myself that prior to ASV my AHI was typically well over 10 for the four months during which I have data, and probably for several years before that. But based on what I've figured out so far, I feel best when it's below 3.

I am concerned about those really long obstructive apneas you're getting, even if they are isolated, and you might want to raise those with your doctor.

I have a followup visit in a few weeks, at which time I'll discuss that.

I come back to our original discussion - pressure support treats central apneas and EPAP treats obstructive events (hypopneas and obstructive apneas). However this needs to be nuanced considerably more than my limited knowledge allows. I have read an excellent paper by Javaheri, Brown & Randerath which goes into great deal of detail about how the algorithms of the Resmed, Philips and Weinneman machines work. I was interested to note that on the Philips, if hypopneas are detected it raises PS first followed by EPAP if there is no response to the PS increase. (Which I think is more or less what palerider said). On the other hand, the same machines do a "proactive search" to determine optimum pressures and will raise EPAP in response to hypopneas. The paper can be found here: http://journal.publications.chestnet.org...id=1891790

Thank you. That's going to take some study.

1. Check your settings to ensure you're in the auto EPAP mode (however that is described in Philips-speak). It looks like your EPAP is fixed on 9 and not varying. Otherwise don't make any further changes for at least a week

SH says I'm in "ASV (Variable EPAP)". I'll check what the machine says.
Based on SH, it looks like EPAP varies, but not that much. I don't know what expected variation is. The min value was 7.8 and max was 11.3 last night. (AHI 4.6, one OA, not lengthy).

2. Do not review your data every day - this can become an obsession which detracts from the real purpose of the therapy which is to get refreshing sleep

I hear you. That's pretty much what the sleep doc said last fall when I was getting agitated about the numbers on the DreamStation.

I have to say I believe there's a significant psychosomatic component to all this, which is not to say that it's entirely psychogenic. But I do think anxiety about AHI, CAs, OAs, and so on is conducive to increases in them. Not an easy not to crack for my personality type.

3. Do keep a sleep diary where each morning you note how you feel, what sort of night you had and whether you can make it through the day without excessive sleepiness.

Good idea. I pretty much always feel fine in the morning, but it's a question of whether later in the day I start to feel hungover, for lack of a better word. After a "bad" night, I'll notice things like sensitivity to glare and loud noises, which ordinarily wouldn't bother me.

5. Do something about those long obstructive events. Talk to your doctor, maybe consider whether you might have a positional problem (eg head flopping forward onto your chest) which could be exacerbating the obstruction.

Yes, I suspect something like this--especially back sleep. I've known for some time that if I end up on my back I'm likely to have a bad time, such as a nightmare of suffocating. Shouldn't there be an alarm in these machines when there's a prolonged OA?

Hope this helps

Yes, thank you.

Edit: For the record, I just found that the highest possible PSmin setting on my machine is 2, which is where I have it. The tech had set it to zero when it was delivered, and the titration study specified zero.