Have you ever woken up from an obstructive apnea?

Had a strange experience last night around 3:30 in the morning. I was dreaming I was suffocating, like my nasal passages were closed up and I was inhaling as hard as I could and could not get any air. I woke up and still felt like this in my half-awake state. The memory is not clear. The machine was on and air was blowing out the vent so I don't think there was anything wrong with the machine nor did the tube seem clogged. I took off the mask and my sinuses were clear - I could inhale easily. So it was not obviously the machine nor was it obviously my sinuses. (I use nasal pillows and mouth tape.)

Looking at the data this morning I can see a number of obstructive apneas and the machine going pretty high trying to open my air passages before I woke up.

I guess this means my throat closed up while I was asleep and the machine could not force it open before the suffocation woke me up?

Here is an OSCAR graph showing the whole night. I had problems later relating to the mouth tape coming undone and air blasting out, waking me up, but that seems unrelated.

Curious if you've ever had an apnea so severe it woke you up while the machine was trying and failing to open it.

Is it possible bedding (or your cat) just blocked things for a minute but was gone by the time you were awake?

Blocked what? The air intake for the machine couldn't be blocked, the machine is on a shelf on my nightstand. I don't have a cat. If the intake was blocked I don't see why OSCAR would show it blowing at high pressure nor the obstructive apneas, of which there are a bunch around that time.

The output wasn't obviously blocked because air was still blowing out the mask vent. Unless a very large insect crawled somehow into the tube and blocked it enough to reduce airflow, I don't see how output could be blocked or reduced. It's kind of creepy thinking about it. I take the water tank out every day to dump it out and let it dry out, so I guess it's possible something crawled into the machine. Ugh.

Before I started using a PAP it wasn’t uncommon to be woken up by an apnea. Since using a PAP, as an allergy sufferer I sometimes get woken up because nasal congestion/ irritation sometimes prevents me from getting enough air through my nasal mask (sounds like your nose was clear).
I’ve also had a few occasions where really bad nightmares have caused me to wake up gasping for breath with heart pounding. A such incident that happened very recently was when I had to chase a black bear of my front porch right before going to bed, that night I awoke in a panic and gasping for air because I had a horrible dream that the bear killed my dogs.

I’ve heard stories of people dreaming about suffocating when their OSA is untreated, so perhaps the apneas led to the dream and the physical feeling of not getting enough air in your case. But another possibility perhaps is that a bad dream could have led to panicked breathing which possibly caused your machine to flag a bunch of events. Perhaps the combination of a horrible dream and panicked breathing could have been what woke you up.

Well looking through the past month the pressure never went above 13. This time it skyrocketed to 17 before I woke up and took it off. Something strange definitely happened.

I have noticed a correlation between nightmares and difficulty breathing.
The content of the disturbing dreams include running,
trying to complete an impossible task, and drowning.

Have you forgotten that apap mode machines don't do a damn thing during the apnea event(s). They sit by and twiddle their little thumbs waiting for the apnea to end and THEN they will evaluate things and increase the pressure in an effort to PREVENT further airway collapses. They can't blow past the obstruction with higher pressures and they won't/don't even try.

I suspect the increase in pressure was likely because of the past (but resolved) OAs along with the increases we see at times in the flow limitation graphs. Flow limitations and snores (you don't seem to have a problem with snores) will also drive the pressures upwards because they are the very early warning signs that the airway is trying to collapse.

If what happened last night is something you have occur on a fairly regular basis then I would suggest maybe a little more minimum pressure to better prevent that clustering of OAs and it would help with the flow limitations as well.
Or maybe add in a bit of EPR if the FLs persist with clustering.
If a one off weird fluke night I would just ignore it.

Couple of things that might cause a weird fluke night.
Perhaps you were on your back more when those clusters occurred.
Perhaps you did the chin tuck thing that seems to narrow the airway even more and increases the chances of the airway tissues collapsing more from that already narrow passageway.
Perhaps even REM related clustering or a combination of REM or supine sleeping or chin tucking.

Thanks for the replies. The more I think about it the more it sounds like it was caused by a nightmare. About ten days ago I stopped using (legal) hemp products because I was starting to develop symptoms that I recognized as being the prodromal phase of CHS. I have been having withdrawal effects but had not had serious dream disturbances until now. But the timeline fits.

"Nightmares: Nightmares and other forms of vivid dreams are also common in the later stages of withdrawal. They typically start about a week after last use and last anywhere from a week to a month."

Just another batch of fun from this process I guess. Well it is less scary now that I know what it is. Thanks again all.

Suffocation nightmares were really common for me before CPAP treatment. Used to have a recurring one with a coffin where I had been buried and only had a straw from the coffin to the surface to breathe through that occasionally was clogged. In retrospect was probably a mix of sleep paralysis and apnea a mixed state waking from the nightmare. I can say that losing those nightmares was one of the nicer benefits of CPAP treatment.

By the way congrats on recognizing CHS and taking action on that - CHS can take some time to settle down too episodes don't usually vanish for a couple of weeks at least but slowly get better - and during withdrawal tendency towards nightmares does slowly recede as well. We have seen a lot more of it in clinic the last couple years. Most of the time patients don't want to try without the cannabinoids until we have ruled out every other GI issue imaginable that might be responsible for the vomiting, especially since they remember starting something like CBD might have initially settled down some nausea. If it initially helped nausea how could it be the cause of vomiting now? Of course keep an eye on it - cannabanoids aren't the only thing that can cause vomiting.

Thanks. I never got to the vomiting stage fortunately. Just other strange symptoms - feelings like hunger pangs (after I had eaten and was full), weird moving little stomach cramps that would move moment by moment from one area to another, occasional random queasiness that I always would think was covid coming on (but always tested negative).

The nausea did not start until 4 days after I quit. I had no idea cannabis withdrawal was a thing. Well it is.

My apnea events in the last three days have doubled from 2 to 4 AHI as I have entered the "return of REM sleep" phase. Average pressure is up from 11 to 13.5.

Has your clinic seen CHS just from CBD usage? Or was THC always involved?

This is getting quite extraordinary. Machine said 5.9 events per hour (0.5 central). I've never seen a number over 5 the whole time I've used CPAP (since early 2017). I usually am at 1 or 2. Last 4 nights have been 3.6, 3.6, 4, and now 5.6. Leak 2L which is nothing. Pressure was 16.2 on the machine sleep report, usually it's around 11. Surprised the nasal pillows have not leaked more with that pressure. The aerophagia and morning tooting are naturally also quite high.

Unfortunately the blue sensitive skin tape I am using tends to start coming off due to saliva, and air blowing out the corner of my mouth keeps waking me up until I am fully awake enough to put a third or fourth piece on the area. This is with several pieces of tape, one partially layered over the other. I will have to start putting on 4 or 5 pieces using the bathroom mirror to set it up before I go to bed. Don't think I should be using the white tape right now since I don't think I could force my mouth open with the white tape on, would have to use my hands to peel off the tape, and if I get a surprise nausea/vomiting episode (would be the first one, but you never know) I might not have time/awakeness to be able to do that. Wish they made the blue tape in 2 inch wide width, a longtime frustration.

I wonder if I should raise the machine's minimum pressure. Currently set at 8 which used to be fine.

If I fall asleep without my CPAP, an apnea will wake me up pretty quickly--within a minute or two. I really don't know how I ever managed to sleep before CPAP.

For the benefit of anyone Googling "cpap" and "CHS" in the future....here are some graphs.

Last day I took hemp gummies was August 8. Sleep disturbances begin about ten days later.






Last night was the worst yet for pressure and AHI.







I think I will adjust minimum pressure to 11 for awhile. 8 seems too low for what I am going through with this right now.