Feedback on a typical recent night

[tbirdwilson]

I'd appreciate some experienced eyes on data from a typical "bad" night on CPAP for me. I'm in my 4th week, and though I've had a few nights under 5 AHI, my overall average is 13 and I run generally between 5-10 using the Amara View. My first two weeks were constant mouth leaks with Dreamware mask, and then I switched. I was prescribed a fixed pressure of 7cm, and have bumped up in half steps to 8cm. On this night, I wore the Dreamware mask with tape over mouth. Had a clear nose that became stuffier. My assumption is that the stuffy nose may have contributed to the steady climb in AHI starting around 2:30am. Before that, I was at or below AHI of 4. But perhaps there's other interpretations of the data? Would love to hear some thoughts and interpretations.

Appreciate it...

[Julie]

Not having read through your earlier posts, I'm curious why you're on plain Cpap vs Apap, and how you came to settle on that pressure level... and whether or not you've tried a lower humidity setting to see if your stuffy nose improves as it often will when less humidity is needed to suit local conditions.

[tbirdwilson]

Good question. I'm following the prescription I was given...err, sort of, since I've begun changing my settings. I was given a machine that was already set for 7cm a month ago, and then given an appt. for a month from now.
So two months without feedback from the sleep doctor to just see what results. I've just assumed this is typical. I was told they had my AHI under 2 during titration with 7cm, but I slept about three hours and I'm sure I never entered deeper sleep.

I haven't dropped the humidity settings. Yes, I'll try it. But I'm definitely battling seasonal allergies.

Thanks...

[Pugsy]

What humidity setting are you using?
Are you using the heated hose?
Is it common for you to be fighting seasonal allergies at this time of year?

If your AHI was running less than 4 until the allergies kicked in I am thinking that most likely the bulk of this ugliness is related to congestion.
You obviously slept poorly as we see multiple breaks in the therapy line. Is it possible there were even more times awake but you kept the mask and machine on?
I am inclined to think that your original assessment of blaming it on the allergies/congestion is probably a correct assumption. It becomes a situation where the data becomes unreliable due to illness...just like when people have bad cold and their data gets all whacko.

[tbirdwilson]

Humidity at 3. Heated hose turned off.

I was up for about 1/2 hour reading with the machine on at first. Choppy nights are pretty typical for me. Up to pee, and then a couple of times awake shifting position. Looking at a month's overall data, it seems there is a rising trend in AHI in the second half of my night's sleep. Not every night, but most. Seems to climb from around 3-6am. But I've had a stuffy nose essentially the entire month I've been on CPAP. So maybe this is the main factor. I also wonder how much sleep position is involved. I start on my side and perhaps shift to my back at some point.

The machine has been indicating a lot of periodic breathing (3-6%). That's essentially centrals, yes?

[Pugsy]

The machine has been indicating a lot of periodic breathing (3-6%). That's essentially centrals, yes?

Actually no. Periodic Breathing is just a waxing and waning of the air flow that lasts for a certain amount of time.
Centrals can be involved but PB can be such that there are no events of any kind flagged during the PB or there can be hyponeas, OAs or even centrals. One doesn't necessarily mean the other and people can have a ton of centrals and not necessarily much PB.

The ClearAirway flags you see are centrals.

Given where your PB is flagged at...my first suspect would be some awake/semi awake breathing irregularity getting the flag...especially that last PB flag right before you turned the machine off.

The higher AHI or event count in those wee hours of the morning are most likely related to REM sleep (and maybe some supine sleeping) because those wee hours of the morning are when we typically get more REM Sleep and it's common for OSA to be worse in REM sleep and/or need more pressure during REM (just like it's common to need more pressure when sleeping on one's back).
REM typically comes on around 90 minutes after first sleep onset and as the night goes on REM stages come on sooner and last longer with the biggest blocks of REM happening in those wee hours.

Centrals aren't all that common in REM (if I remember right) and your machine doesn't respond to centrals at all.
If you were in auto mode the machine would only respond to snores, flow limitations and the OAs and hyponeas.
It ignores the centrals other than flagging them.

In fixed mode your machine doesn't flag Flow Limitations at all...so your absence of FLs doesn't really mean much...I am betting you also had some FL and if you were in auto mode I bet you would see some FL flagging.

I would suggest going to auto mode so that FLs become available. You can mimic fixed cpap mode while in auto mode simply by setting the minimum pressure and maximum pressure to equal each other.
You might also consider a small apap range just to see if the machine wants or needs to go higher in those wee hours of the morning. Then if it does you can decide if you want a larger range or not or if you wish to just use a higher pressure all night to cover the pressure needs in those wee hours of the morning (whether its REM or supine sleeping).

The ClearAirway/central component of your AHI kinda has to be ignored when it comes to pressure needs evaluation because they can't be fixed with more pressure with your machine and that's assuming they are real centrals and not awake/semi awake breathing getting flagged by mistake. If they are awake/semi awake stuff...they get totally ignored period.

I think if you slept better that the time in PB would reduce but even if it didn't a less than 10% PB number probably isn't all that alarming. Something to discuss with your doctor for sure though if it bugs you.

[Pugsy]

The setting of 3 with a non heated hose is the middle of the road setting in terms of humidity level since it goes from 1 to 5 when the heated hose is not used.
If using a heated hose then it is the max setting.

Here's the deal about humidity needs...some people need more and some people need less to keep the nasal mucosa happy.
It's an individual preference thing and something that you need to figure out. There is no right or wrong setting other than what works for the individual.
I happen to need a maximum setting or I get some nasty congestion. I find more humidity helps...sort of like how your nose feels in a hot steamy shower type of setting but maximum isn't hot and steamy.
Julie does better with minimal to none added humidity.

I would suggest trying both lower and higher setting to see which your nose prefers especially since you are saying the congestion started with the start of cpap.
Google "cpap rhinitis"....it is a common complaint.
Which way to try first? If playing the odds...most people need a little more but it wouldn't be a big surprise if you needed less. Read up on what you find with that cpap rhinitis google search.

[robysue]

Looking at a month's overall data, it seems there is a rising trend in AHI in the second half of my night's sleep. Not every night, but most. Seems to climb from around 3-6am.

REM cycles get progressively longer as the night goes on. And some of that late night ugliness could be due to hitting REM for some extended periods.

Out of curiosity: How much REM did you get on your diagnostic sleep study? And how much did you get on your titration study?

I also wonder how much sleep position is involved. I start on my side and perhaps shift to my back at some point.

Many people's OSA is worse on their back and they need more pressure when they're on their back to control the OSA. How much supine sleep was recorded in your diagnostic sleep study? And how much supine sleep was recorded on the titration study?

If you are sleeping on your back in longer REM cycles between 3 and 6 am, that could very well explain the ugliness. And indicate that you were under titrated on your diagnostic sleep study. The most obvious causes for an under titration are lack of sufficient REM and lack of sufficient supine sleep during the titration sleep study.

But I've had a stuffy nose essentially the entire month I've been on CPAP. So maybe this is the main factor.

While the stuffy nose may be making things worse, I think that's not the main problem. I think you probably do need some additional pressure to control what's going on late in the night.

That said, it is worth trying to deal much more proactively with the congestion problem. If you can take a daily antihistamine during your allergy season, you will probably breathe better both during the day and at night. If OTC antihistamines don't work, you might want to talk to your regular doctor about a steroid nose spray like Flonase. Daily use of a neti pot or saline rinse can also make a big difference.

The machine has been indicating a lot of periodic breathing (3-6%). That's essentially centrals, yes?

No, periodic breathing is not the same as central apneas. Periodic breathing is a distinctive waxing and waning pattern in the size of the inhalations. It is possible for the waxing/waning cycle to be so pronounced that the nadir of each cycle results in a central apnea being scored. But a lot of times the PR machines will score things as PB that do not come close to bottoming out in a CA.

Given that you are seeing 3-6% PB on some nights, you should zoom in on the parts of the flow rate that are flagged. Looking at the flow rate itself is usually the only way to really figure out whether the PB is something you need to worry a lot about. If you don't know what you are looking at when you zoom in, post some pictures showing us what the PB looks like when you zoom in far enough to see individual breaths. And also post some pictures of what your breathing looks like when there's nothing being flagged so we can see what your normal sleep breathing usually looks like.

[tbirdwilson]

I unfortunately don't have any of my sleep study info. I'll make sure to ask at the next meeting.

I know this has been asked many times, and I've done some research on it, but I'm wondering at what point, and by what criteria, is complex sleep apnea judged as such? I know it's early in the game, and I haven't even really had pressure adjustments above 8cm yet, but I do know that the home study I did suggested complex sleep apnea. But the folks at my sleep study, and my sleep doc, seemed to naysay that. So I'd love to know what diagnostic criteria would rule it in or out.

[Pugsy]

Home sleep studies sometimes aren't the best at distinguishing centrals as in which central is a real central or which central is really an awake pause in breathing which isn't real and of course there are the centrals that are normal occurrence during sleep stage transition or what we often call sleep onset centrals.
Obviously the awake central is omitted from evaluations.
Sleep onset centrals are usually set aside unless there's a large number that are causing desats or trouble staying asleep. Those are usually evaluated on a case by case basis and hard to give a numerical data point that covers all the bases.

People see centrals and the knee jerk reaction is "OMG I have obstructive sleep apnea and now I see centrals so I must have Complex sleep apnea" and they start worrying and often worrying needlessly.

Usually when centrals are considered problematic we see a high proportion of the AHI being central and of course won't respond to the pressures or the centrals are made worse by pressure increases. Also the centrals that are considered problematic seem to occur all night long in relative high numbers every hour...every night....and they have to be real centrals as opposed to awake/semi awake breathing irregularity getting flagged by mistake.

So maybe 5 centrals per hour...every hour for the most part and every night and you were for sure sleeping...would warrant some concern.

I don't see your report screaming out "compSA" at this point. Not enough centrals on a consistent basis that can't be explained away easily.
I once saw a report from a guy who we thought for sure had compSA because his AHI was 20 and the majority of the events were central and he had some really ugly reports. We did some fact gathering and it was noticed that we saw some breaks in therapy which means awake and turned the machine off. So more fact finding and it was discovered he was spending a LOT of time awake and trying to get to sleep and lots of tossing and turning with the mask and machine on..
So we did an experiment where he made sure that if he was awake for more than 10 minutes the machine got turned off and he no longer spent hours awake with the machine on. His AHI dropped to just a little over 2 per hour and no centrals at all.

[robysue]

So maybe 5 centrals per hour...every hour for the most part and every night and you were for sure sleeping...would warrant some concern.

I don't see your report screaming out "compSA" at this point. Not enough centrals on a consistent basis that can't be explained away easily.

I agree completely. There's nothing in your report that screams out "compSA". There are things that suggest that you might need a bit more pressure in the later half of the night when REM is more common, particularly if you have a tendency to flip on your back.

Same thing with the PB: Unless a zoomed in view of the PB shows something clearly alarming, the 3-6% PB being scored is not something to lose sleep over.

[palerider]

how about switching over to auto min 8, max 10 and seeing if a little more pressure will tame the rem hypos and apneas, hopefully without exacerbating the centrals?