Central apneas

[retired_guy]

Anything scored when you're awake really doesn't mean anything. It's what happens when you're not awake that may or may not be a problem.

[Sleepster]

I tried some deep slow breathing just before I got up this morning and was scores a central when I was doing that. When I look at the mask pressure/flow I saw the graph is different to the other centrals.

If the flow meter registers no flow or very little flow over and above the baseline for 10 seconds or more it scores an apnea.

You see the oscillations in the pressure during this time? Those oscillations are being used in conjunction with the pressure sensor and flow sensor readings in an attempt to determine if your airway is obstructed.

Based on those readings if it's determined that your airway is open, the type of apnea scored is a central apnea.

Also when I look at the mask pressure/flow graphs for a central and obstructive, they look identical.

It's the way the flow meter readings respond to those pressure oscillations that's different. I don't know if that can be seen in the flow graph.

I suppose the worst thing is that I have the software and am looking at the figures....

Well, yeah, it's a common syndrome to get caught up in reading the data.

When electronic computers first became available to us some people just couldn't stop playing with them. It was just too fascinating to see how they did the stuff we told them to do. Richard Feynman called it catching "the disease".

This is the same sort of thing.

[robysue]

I tried some deep slow breathing just before I got up this morning and was scores a central when I was doing that. When I look at the mask pressure/flow I saw the graph is different to the other centrals. Also when I look at the mask pressure/flow graphs for a central and obstructive, they look identical.

Wake breathing is different from sleep breathing.

And wake deep slow breathing is VERY different from sleep breathing.

And many kinds of (common) wake breathing patterns can get mis-scored.

There are two things that are needed to score an apnea of some sort:

1) There is a 90% drop (or more) in the size of the inhalations.
2) The "reduced inhalations" must last for at least 10 seconds

Now in my case, my normal sleep breathing inhalations usually top out at a max of about 15 L/min. So to score an apnea, the peaks on the inhalations have to be LESS than 1.5 L/min, or "essentially 0".

If I'm doing REALLY DEEP inhalations, those inhalations can reach a max of 60 (or more) L/min. At this level of breathing, all it takes to score an apnea is for the peaks on the inhalations to drop to 6 L/min, (a bit more than 1/3 of my normal sleep inhalations) and stay there for 2 or 3 breaths. And eventually after doing a series of deep inhalations I will reach a point where I don't really need to inhale as much and the pause between the exhalation and the next inhalation grows a bit. Under the right circumstances, it is indeed possible for me to "miss a breath or two" and the machine (thinking I'm asleep) scores a CA or an OA that doesn't look anything like a real CA or a real OA.

[vsheline]

Also, the machine often flag things as centrals that aren't "real" apneas in some sense. It's often something like swallowing, rolling over in bed, waking up, etc.

Actually, swallowing is obstructive, but it would not last 10 seconds, and therefore swallowing will not qualify as an "event".

[archangle]

Also, the machine often flag things as centrals that aren't "real" apneas in some sense. It's often something like swallowing, rolling over in bed, waking up, etc.

Actually, swallowing is obstructive, but it would not last 10 seconds, and therefore swallowing will not qualify as an "event".

One would tend to think that, but maybe not. During the actual mechanical swallowing process when the tongue, epiglottis, etc. are doing their thing, yes. If you pay careful attention, there's often some "preliminaries" before where you sort of get ready, work the goo around, etc. before the actual "close off the throat and push the stuff down the esophagus" phase. I find I also may hold my breath for a while after the swallow as things settle. This may last longer and may not necessarily be obstructive.

[PaytonA]

Also, the machine often flag things as centrals that aren't "real" apneas in some sense. It's often something like swallowing, rolling over in bed, waking up, etc.

Actually, swallowing is obstructive, but it would not last 10 seconds, and therefore swallowing will not qualify as an "event".

One would tend to think that, but maybe not. During the actual mechanical swallowing process when the tongue, epiglottis, etc. are doing their thing, yes. If you pay careful attention, there's often some "preliminaries" before where you sort of get ready, work the goo around, etc. before the actual "close off the throat and push the stuff down the esophagus" phase. I find I also may hold my breath for a while after the swallow as things settle. This may last longer and may not necessarily be obstructive.

I do not eat with my mask on let alone with the machine connected and turned on. Swallowing when you are not eating is a little less complicated and somewhat quicker.

Best Regards,

PaytonA

[Sleepster]

I do not eat with my mask on let alone with the machine connected and turned on.

[diamaunt]

I do not eat with my mask on let alone with the machine connected and turned on. Swallowing when you are not eating is a little less complicated and somewhat quicker.

I found that I can eat and drink with nasal pillows and the machine on... handy

[Sleepster]

I found that I can eat and drink with nasal pillows and the machine on... handy

Wow! I can barely talk with mine on. Now, sometimes if I get up for a midnight snack I might forget to remove my chin strap. But as soon as I start chewing I remember.

[diamaunt]

yeah, you hear some people talking about 'pressing the tongue to the roof of your mouth to create a seal', and other bits...

doesn't work for me, I can open my mouth and stick my tongue all the way out and no air comes out.

I can also 'switch things' and breath in and out through my mouth with the cpap on my nose.