Hypopneas

[n3kf]

Hi All,
I can post some charts, but just interested to gather information before seeing my pulmonologist Tuesday. I have a new (new due to recall) Dreamstation DS1. My problem is being retired I tend to go to bed late. My AHI is great until about 5AM or a little later. From that point on, I throw a bunch of hypopneas. Now I am a shallow breather and that's not going to change. It appears the DS is interpretating my shallow breathing as hypopneas. Normally I would not care, but with these hypopneas occurring one right after another, the system just keeps raising pressure on me. This continually wakes me up. When it gets bad enough I just pull the mask off and say screw it. I can actually lay in bed with the mask on and let my breathing get shallow. The system responds just as I stated above, but I am definitely not short of breath.

So speaking as an engineer, I a assuming this is integrated into its algorithms. That is what it thinks is a hypopnea is not really one for me. Is there any adjustability to this, or is it that the DS is probably not the right system for me? I can get CAs and regular apneas, but the system keeps those in check fairly well. Some mornings its not much of a problem, but others it is just not worth having the mask on in my mind. I also don't understand why if I go to sleep at 10PM and get up at 5am, the hypopneas are few and far between. But if I go to sleep at 1am (more normal for me), all hell breaks out with hypopneas at 5 or 6AM.

[Julie]

You didn't mention it, but hypops are known to multiply a lot if you back-sleep... can you try side sleeping instead even if it means wearing a back or fanny pack to stay there when asleep?

[ChicagoGranny]

I also don't understand

We will never understand unless you post a Daily View screenshot from OSCAR. Instructions near the top of the index page.

You didn't mention it, but hypops are known to multiply a lot if you back-sleep... can you try side sleeping instead even if it means wearing a back or fanny pack to stay there when asleep?

We would like to get his machine set for any position he chooses to sleep in and not tell him to wear a %#$@ backpack.

[Julie]

Sure, and I'd like lots of things, but you have to start somewhere to get him better than he is now.

[n3kf]

You didn't mention it, but hypops are known to multiply a lot if you back-sleep... can you try side sleeping instead even if it means wearing a back or fanny pack to stay there when asleep?

I am a side sleeper. Can't sleep on my back at all

[n3kf]

I also don't understand

We will never understand unless you post a Daily View screenshot from OSCAR. Instructions near the top of the index page.

Will give it a try.

[lazarus]

The longest period of REM tends to happen toward the end of sleep. REM, for many, can be when effectively optimized PAP is needed most. Hypopneas can kick you out of REM. So treatment machines generally need to be titrated to prevent airway narrowing in supine REM, even when patients swear they are never supine. For APAP, in practice, experience has shown that can mean getting minimum pressure set to within a cm or two of what is needed to prevent apnea in REM for those with REM breathing issues.

[ozij]

The longest period of REM tends to happen toward the end of sleep. REM, for many, can be when effectively optimized PAP is needed most. Hypopneas can kick you out of REM. So treatment machines generally need to be titrated to prevent airway narrowing in supine REM, even when patients swear they are never supine. For APAP, in practice, experience has shown that can mean getting minimum pressure set to within a cm or two of what is needed to prevent apnea in REM for those with REM breathing issues.

My thinking was similar.
Adding emphasis: "experience has shown that can mean getting minimum pressure set to within a cm or two of what is needed to prevent apnea in REM for those with REM breathing issues." With the aim of a) preventing all hell breaking loose and b) the machined playing catchup.

Does the replacement machine have the exact same settings as the one it replaced? Maybe you received it on default settings?

However, the following is still an unanswered question:

I also don't understand why if I go to sleep at 10PM and get up at 5am, the hypopneas are few and far between. But if I go to sleep at 1am (more normal for me), all hell breaks out with hypopneas at 5 or 6AM.

Especially, why that doesn't happen 4 hours into your sleep when you go to sleep at 10PM. I'm assuming your basing that statement on OSCAR.

As for:

So speaking as an engineer, I a assuming this is integrated into its algorithms. That is what it thinks is a hypopnea is not really one for me. Is there any adjustability to this, or is it that the DS is probably not the right system for me?

Yes, it's built into the algorithm, and yes other machines have different algorithms -- which is no to say others will be better if the minimum pressure is too low.

Now I am a shallow breather and that's not going to change.

This is what you have to discuss with the pulmonologist, and if its effect on your oxygenation, and arterial blood gases has never been checked, maybe it should be.
Not that I'm saying you have it, but there is such a thing as Obesity Hypoventilation Syndrome, which is treated by a totally different machine, which responds to volume, and not to flow.

[n3kf]

The longest period of REM tends to happen toward the end of sleep. REM, for many, can be when effectively optimized PAP is needed most. Hypopneas can kick you out of REM. So treatment machines generally need to be titrated to prevent airway narrowing in supine REM, even when patients swear they are never supine. For APAP, in practice, experience has shown that can mean getting minimum pressure set to within a cm or two of what is needed to prevent apnea in REM for those with REM breathing issues.

But as I had said, I can get myself into a relaxed state where my breathing gets shallow and I can reproduce what is happening. And definitely not happening in a supine position. I am very aerobically fit, so at rest my breathing can almost be non existent and it seems to work fine for my body.

[n3kf]

So saw my pulmonologist today. He said he was surprised I hadn't experimented with settings. He knows I was an engineer. Also I had made minor changes in the past which he was aware of and was ok with. The system was set exactly as the old one when I got it. Phillips seems to be much more cautious on getting the ASV variant set right. Usually via the DME but that was another horror story!

Anyway, my EPAP was set at 4 and my 95% time is 5.5 so he said let's raise that to 5. He also lowered PS. I have not looked at it to see what he set it to yet. The machine has done a great job with my centrals, and don't want to change that, but he said that's yet another algorithm. So we shall see.

After I get a few nights in I'll report back if he helped it or not. If not I'll put some charts up and we can go from there. Thanks for the comments so far! It's appreciated

[lazarus]

I can get myself into a relaxed state where my breathing gets shallow and I can reproduce what is happening.

There is no way while awake to exactly reproduce sleep breathing, since the drive mechanism and some muscle function changes. And REM breathing is truly unique.

"The diaphragm and accessory muscles of respiration are differently affected by sleep. Diaphragmatic function is largely preserved, which is essential for the maintenance of adequate ventilation during sleep. However, accessory muscle function is reduced, particularly during REM sleep."--https://pubmed.ncbi.nlm.nih.gov/12814041/

[n3kf]

I can get myself into a relaxed state where my breathing gets shallow and I can reproduce what is happening.

There is no way while awake to exactly reproduce sleep breathing, since the drive mechanism and some muscle function changes. And REM breathing is truly unique.

"The diaphragm and accessory muscles of respiration are differently affected by sleep. Diaphragmatic function is largely preserved, which is essential for the maintenance of adequate ventilation during sleep. However, accessory muscle function is reduced, particularly during REM sleep."--https://pubmed.ncbi.nlm.nih.gov/12814041/

Maybe not, but I'm getting hypopneas while awake with my shallow breathing. And I know I get woken up from the same pressures and seeing similar waveforms. So it's close enough for me.

[ozij]

I have a new (new due to recall) Dreamstation DS1.

Phillips seems to be much more cautious on getting the ASV variant set right.

You're already using an ASV, an "Auto Servo Ventilation" machine? The engineer in you didn't feel the need to report that in your first post?

Maybe not, but I'm getting hypopneas while awake with my shallow breathing. And I know I get woken up from the same pressures and seeing similar waveforms. So it's close enough for me.

The machine is identifying you shallow breathing when you're awake as hypopneas. So what? It's "close enough for you" for which purpose?

[palerider]

It appears the DS is interpretating my shallow breathing as hypopneas.

See, your understanding of what's happening has gone off the rails there.

The machine *does not care* whether you're "very aerobically fit" or not. It does not flag a hypopnea because your tidal volume is less than some predetermined amount.

If flags a hypopnea because your tidal volume has reduced to something like < 50% of what your previous tidal volume a minute or two previous was.

That's not "shallow breathing" that's a hypopnea.

[ChicagoGranny]

You're already using an ASV, an "Auto Servo Ventilation" machine?

n3kf

--------> You should put that information in your equipment profile so it shows on every post and comment you make. If there is not a dropdown box for your machine model, put it in your signature.