Please analyze sleepyhead data

[vidiot]

As you read this post, please refer to the following URLs for the sleepyhead screenshots
http://www.fredcrystal.com/images/scree ... 084427.png
http://www.fredcrystal.com/images/scree ... 084435.png
http://www.fredcrystal.com/images/scree ... 084443.png
All three refer to the same episode.

I had an episode last night that was bad enough that my wife poked me and asked me if I was okay. This was somewhere around 2:30 to 2:35 am. She said that my CPAP sounded like a prop plane and it was really pushing the air. I didn't really feel like it was pushing that much, nor do I see that the data says that it was. I can tell when I woke up, at 2:36am. But I can't tell really what triggered what my wife heard. I'm assuming that what the machine marks as a RERA, is really her waking me up.

But I don't know how to interpret the data before then.

It took me a while to get back to sleep, because the whole thing really bothered me. My wife doesn't usually do this, so this really has my attention. I finally got up, got a drink of water and ate something and stretched, then laid back down, and was finally able to fall asleep.

Any help is appreciated!

Thanks,
Videot.

[library lady]

The only thing I can see, and it's just a guess, is a big spike in tidal volume. I'm not sure what happens when there's a spike in volume, but someone with more expertise than I in interpretation of sleepyhead will probably come along.

[FromOZ]

I'm going to invoke the same disclaimer the SleepyHead author states in his software "...has not been approved in any way for compliance or medical diagnostic purposes".

If you are concerned then then really you should be discussing the episode with your health care professional provider, I'm sure you will.

Re: your screenshots, like 'library lady' I would say that the sudden increase in the tidal volume numbers are relevant, both the amount and the sudden onset. That, plus the fact that you had three OA events in quick succession, would tend to indicate that there was a mechanical obstruction to breathing which your device was attempting to compensate for. We don't see flow limitation numbers in your charts — did they spike as well?

Of course as to the cause of the episode we are all guessing — again it would be good to discuss with your health care provider.

[p.s. if you use the 'Img' BBCode tag then you can embed your screenshots in your forum post, makes it easier for readers to follow]

[OhHelpMe]

No wonder you feel like crap. Your minimum is set too low. Turn it up to 8 and post your reports again.

[FromOZ]

No wonder you feel like crap. Your minimum is set too low. Turn it up to 8 and post your reports again.

Hi — I was wondering about that on the OP settings, I've also seen other SleepyHead screenshots where people have minimum pressure of 5, and I've seen people with many events per night. My machine is on APAP mode of 8—14 and (fortunately) I am able to get my current average (two months) AHI down to around 1.20. Screenshot below of a good night I had recently.

Anyway regarding the OP case... I'm curious, because during the three OA events the pressure being delivered by his machine was around 5—7 cmH2O. Shouldn't the machine, as it was running in APAP mode, have increased the pressure as required to keep the airway patent? I thought that was the whole idea of the sophisticated algorithms in the machine. Or, regardless, does the machine need to have a 'baseline' minimum pressure high enough to keep the airway open? But again, then, shouldn't the machine be able — in APAP mode — to figure that out itself.

I'm just curious as I am also doing my own investigation and learning into all of this as well as, of course, trying to get my own therapy consistently working well.

[Pugsy]

does the machine need to have a 'baseline' minimum pressure high enough to keep the airway open? But again, then, shouldn't the machine be able — in APAP mode — to figure that out itself.

Yes, there is a "baseline" of sorts where the minimum pressure needs to start at to help stent the airway open better and give the machine a better head start should it sense the airway collapsing. APAP machines don't increase the pressure in a blink of an eye in response to the warning signs that a collapse of the airway is maybe happening. Warning signs being snores or flow limitations.
Sometimes people can have what we call "frank" apneas where the airway just collapses without any of the usual warning signs.
No way to tell for sure what happened in the above situation but the cluster of OAs could have been related to supine sleeping or REM stage sleep or maybe a little of both.

If the machine is set at 5 cm minimum and it's sitting there and something happens that requires 10 cm then the APAP mode machine can't get to 10 cm in 30 seconds. It just doesn't work that way. It's better to prevent something in the first place then it is to have to keep trying to fix it after it is in the middle of happening.

Sometimes all that is needed when a machine is set wide open (the OP pressure setting is 5 to 20) is just a little more minimum pressure. While I don't know that 8 cm minimum is needed I do suspect that 6 or 7 minimum would do a better job in the above situation. Given that the bulk of the events seen in OPs report happens later in the night, I suspect that REM stage sleep may be a factor. It's common to need more pressure during REM stage sleep to hold the airway open than in the other sleep stages and we have more REM in those wee hours of the morning so greater chance to have that increased pressure need.
I have a lot of personal experience with varying pressure needs in REM sleep as that's when my own OSA is much more severe. When I was using the APAP machine if my minimum was too low I would get clusters of events in probably REM stage sleep.

Using a minimum of 4 or 5 works well if a person only needs maybe 8 or 9 cm of pressure to hold the airway open but if someone needs 10 or higher the machine just doesn't have time to get there before the collapse happens.

[OhHelpMe]

does the machine need to have a 'baseline' minimum pressure high enough to keep the airway open?

Correct.

The minimum should be set within two cm of the pressure that your body needs most of the night to keep the airway open.

The algorithm does not raise the pressure until it detects trouble breathing and then it raises it slowly. Who wants to have trouble breathing while trying to sleep?

[FromOZ]

does the machine need to have a 'baseline' minimum pressure high enough to keep the airway open? But again, then, shouldn't the machine be able — in APAP mode — to figure that out itself.

Yes, there is a "baseline" of sorts
[...]
Using a minimum of 4 or 5 works well if a person only needs maybe 8 or 9 cm of pressure to hold the airway open but if someone needs 10 or higher

Thanks Pugsy, so looking at the session screenshot I uploaded, and the stats from the session, the minimum pressure of 8 that I currently have seems pretty good — can't complain when I get only two events in a session!

[FromOZ]

does the machine need to have a 'baseline' minimum pressure high enough to keep the airway open?

Correct.

The minimum should be set within two cm of the pressure that your body needs most of the night to keep the airway open.

The algorithm does not raise the pressure until it detects trouble breathing and then it raises it slowly. Who wants to have trouble breathing while trying to sleep?

Thanks! I hope this information helps the OP also.

[Pugsy]

the minimum pressure of 8 that I currently have seems pretty good — can't complain when I get only two events in a session!

Yep, it's working well for you.
I didn't go into the difference in the 2 algorithms (ResMed vs PR S1) in their response time. It's a bit complicated but the S9 responds a little faster than the PR S1 responds when warning signs of impending airway collapse present themselves.

[vidiot]

Thanks to all for the comments and advice.

I was supine when this episode occurred. I should have noted that in my original comments, because I almost always have trouble with the supine position.

I will adjust my pressure to 7 and see what happens. I have never seen my pressure go higher than 10. If need be, I'll try 8. The machine was at 6.5 when my wife woke me up, so I don't want to freak her out! Of course, I'll explain what I'm doing and why, but I still don't want to concern her too much and keep her from sleeping!

I'll let you know what happens!

Thanks,
Videot

[vidiot]

One week later:

I've had good nights with what I'd call one of my best night's sleep yet. And I've had lousy nights, which were pretty much more of the same. Last night was one of them

Here's last nights:




So anyway, my CPAP woke up my wife around 2:44 am. She says that I wasn't breathing. I'm just guessing on the time, since I don't remember the incident.

I only turned up the pressure to 6. I was concerned that thenoise of the CPAP making the increased pressure would wake her.

And the solution (increased pressure) is going to wake her. so I don't know what to do.

Good night!
videot

[vidiot]

To followup:
I had my annual checkup yesterday, and I had my pulmonologist look over this thread. He said that he saw no harm in taking it up to 8. I didn't get a chance to change it yet, but will do so tonight.

Thanks for your help!
Fred