Polysomnography

[dbebz]

Hello everyone,

Last night, I did the full-on polysomnography inside a hospital's sleep lab. I work evenings so I usually sleep around 1AM, but I had to go to bed at 9pm for this test. I tossed and turned with all the wires on me and uncomfortable bed before falling asleep. Then I woke up at midnight hearing "Code blue blah blah" on the hospital intercom" and tossed and turned for a little while again. At 5:45AM, the technician woke me up and disconnected me. He stated I appear to be in the "moderate to severe" category, but it needs to be scored at a later date. He mentioned I'm having obstructive events, but also mentioned I had a bunch of central apnea events. He stated that it looked like they were only happening "just as you were falling asleep."

I remember the sleep physician telling me a week ago that my at-home test showed some clusters of centrals and that it isn't a concern unless I have an associated medical condition or if they aren't happening during the change between awake and falling asleep. My question is, are they going to "delete" these centrals from my polysomnography if they were occurring just as I was falling asleep? It seems kind of odd for them to include them because I probably was dozing in and out of sleep tons due to sleeping in a hospital bed (I usually sleep straight through the night or only briefly wake up once). Also, should I be concerned about these centrals? I wish I asked more but I was so groggy in the morning from sleeping like a lab rat and the technician had to leave. I had extremely interrupted sleep due to anxiety of the test, the hospital environment, wearing 2 dozen wires and trying to sleep 4-5 hours earlier than I normally do. I am sure I had a good solid sleep between 1am-5:45am though so hopefully that part is accurate.

Thanks for the help!

[khauser]

As part of your test you had an EEG. From that they will be able to tell exactly what state you were when the events occur.

I'm not a sleep tech so I can't give you an absolute answer, but that is my belief ... they will tend to discount events around wake <--> sleep transitions...

[dbebz]

Yes, I had an EEG, hence why I think the tech was saying "around the time you were just falling asleep." I was just worried hearing about central apnea and crap because I read about all the serious medical conditions it can be caused by. Talk about anxiety inducing!

Also, I did the polysomnography because I wasn't feeling much of a difference when I started CPAP and wanted to do the "gold standard" test. In hindsight, I honestly do think the CPAP helped me (I stopped 2 weeks before the polysomnography). I don't have severe symptoms (I don't feel like falling asleep everywhere during the day), but I realized that without CPAP, 8 hours of sleep I feel somewhat groggy in the morning and feel like I could have gotten better sleep. on CPAP, 6 hours of sleep seemed to make me feel a bit better than the 8 hours without CPAP. On 6 hours of sleep without CPAP, I definitely feel it.

Thanks for the reply!

[khauser]

You have to have a bunch of centrals not associated with sleep-wake junk before anyone even blinks.

Interesting, your experience with your temporary stoppage. I'll tell you that before I got my diagnosis and began treatment, I did not feel like falling asleep most of the time. BUT put me in the right conditions (driving home at night after a day out walking in the woods, for example) and I would start to drop off. Lucky for me I have a pretty good driving while asleep response, and even more luckily, I got diagnosed and treated! That NEVER happens now, even if I am otherwise dog tired. The day to day changes in how we feel are subtle, which is why most don't even realize there IS a problem. Some fine out about it after a triggering event (like falling asleep and not being so lucky while driving, or bad effects on the heart after a long time, etc). I consider my path to treatment to be fairly lucky.

Oh yeah, there was my spouse telling me that I snored loud enough to wake the neighborhood, and often gasped! But I don't want to give her any credit because she's now my ex (LOL!)

[dbebz]

Hopefully she didn’t become an ex due to the snoring! And yeah I guess you have to give her some credit. Interestingly enough, prior to my first sleep study I was expecting maybe mild or no sleep apnea, due to the fact that I don’t have any glaring symptoms. The reason I got checked was I’ve been told I snore and make sounds when I sleep, particularly more if I’ve had alcohol. My friend said his brother has sleep apnea so he got me to get it checked out. Surprise. Moderate or even possibly severe.

As a 27 year old male with a relatively normal BMI (I’m definitely not a lean body mass but not overweight for my 6’2” height) I was surprised to find out.

[Julie]

Tip - save your fingers and just type PSG - I can't imagine writing poly... blah blah all day.

[Pugsy]

A few sleep onset centrals are normal to see. They will be counted in the results.
Any centrals flagged when you were obviously awake won't be counted but during the transition...they will be counted. Unless you have a really large number and they keep bouncing you out of sleep or they cause massive desats...docs don't get alarmed with a few centrals.
With the EEG being done in the lab as well they will know for sure if you were asleep or not.
A few central apneas...normal.

Even if you have enough centrals to be a worry....there are ways to deal with them if they number enough to be a problem.
Try not to worry if you can. I know it's difficult but some people just have centrals that are numerous and there are no underlying medical conditions to cause them and they are just dealt with.

The only real negative about having centrals...the cost of the machine to deal with them. It costs a lot more than a cpap/apap machine costs.

[dbebz]

Hi pugsy,

I already have a machine, the ResMed Airsense 10, and have been using it for over a month before my PSG test. My average AHI has been about between 3.0 to 3.5 per hour over the period of that month. If I were having tons of centrals wouldn’t my AHI on CPAP be a lot higher? I believe the doctor mentioned that CPAP devices tend to be quite good at detecting AHI accurately.

When I did the at home tests, it seems like on the first sleep onset at the beginning of the night , I had a bunch of centrals and my oxygen saturation dropped briefly to 83% before jumping back up to 97%. Then the rest of the night it showed a coupe clusters of centrals, but my oxygen didn’t really appear to changed. Other than that big drop at the beginning, my oxygen was usually in the mid 90s and never dropped below 90 the rest of the night.

During the PSG, it was so difficult to stay asleep due to the issues I mentioned before so I’m curious if maybe I had more centrals because I kept waking up and having to go to sleep again. It was so difficult to sleep 5 hours earlier than I usually do so I’m wondering if I was bouncing between that sleep wake time for a prolonged period which maybe showed more. Or maybe the technologist was just curious about I.

FYI, I did the PSG test on MY OWN request. I wanted to know exactly what was going on. The respiratory therapist was not concerned with my sleep study tests because when I started CPAP it appeared to be working.

[Pugsy]

If you were having an alarming number of central apneas your machine would have flagged them.
You would need to be having greater than 5 central apneas per hour (for many nights) average before the doctor would even raise an eyebrow and for sure be asleep or right at the sleep/wake transition.
And yes...if you were having tons of them it would be reflected in the AHI.

Wait to see what the official report says and then talk to your doctor about your concerns.
Your experience with the tech giving you little tidbits...he's not supposed to be telling you anything because he's not the one who does the overall evaluation and what he might think is a "ton" of something doesn't mean it is. The doctor has the final say so.

[dbebz]

Thanks again Pugsy (and everyone else) for all of the informative replies. I definitely have anxiety issues when it comes to personal stuff like my health so you’ve definitely helped chill me out a bit. It’s nice to see so many people on here who have similar experiences and to learn from each other.

[ChicagoGranny]

I definitely have anxiety issues when it comes to personal stuff like my health

It's not clear whether you mean just normal concern or unhealthy anxiety. If it's the latter, you may like to hear that untreated or poorly treated sleep apnea is a major cause of anxiety. You have a lot of good things to look forward to as your CPAP usage progresses.

[chunkyfrog]

The line between normal anxiety and unhealthy obsession has been moved lately.
Updates are irregular and not always reliable.
Always keep saying, "This too shall pass."
Because in similar times in the past, it has.

[dbebz]

Thanks for the wisdom everyone!

On the bright side, last night was the first full night using the machine since I stopped for the PSG. I’ve been tracking closely how I feel to measure the CPAP benefits.

I’ve realized that on 8 hours of sleep WITHOUT CPAP, I was feeling somewhat groggy and felt like I could have gotten a better sleep. With only 6 hours, I am extremely tired.

Last night I slept for barely 6 hours WITH CPAP, and even with interruptions in sleep caused by waking up from not being used to wearing a mask, I woke up refreshed. Barely 6 hours of sleep and I feel ready to go. Wow. And AHI was 2.6 last night.

[dbebz]

Here’s an update (I only received official results from the sleep specialist a couple weeks ago!):

The doctor says I have severe obstructive sleep apnea (AHI 50). Said it’s the worst on my back, slightly better on my left side, and much better on my right side (but still considered moderate if on my right side).

I asked about the central apneas and how the technician said I have central sleep apnea. The doctor said “you did have some clusters of central apneas, but these were only happening around the sleep wake transition. They are also slightly more elevated because when you have an instructive event, you over breathe and when you fall asleep again you’ll have more central apneas. So yes, you did have some central apneas during the study, but you do not have central sleep apneas. Those central apneas are not a sign of disease, it’s normal.”

So that was comforting to hear. But yeah at least I have the official test results.

[Pugsy]

I asked about the central apneas and how the technician said I have central sleep apnea. The doctor said “you did have some clusters of central apneas, but these were only happening around the sleep wake transition. They are also slightly more elevated because when you have an instructive event, you over breathe and when you fall asleep again you’ll have more central apneas. So yes, you did have some central apneas during the study, but you do not have central sleep apneas. Those central apneas are not a sign of disease, it’s normal.”

We call those sleep onset centrals or transitional sleep stage centrals and they are indeed normal and not a big deal unless someone is having a truckload of them causing desats or keeping a person from proceeding into sleep itself. In other words if they keep bouncing a person out of sleep so they don't get to sleep then they are a problem. So it's not so much that you had them that is the potential issue but the number of them that you might have had and did they cause a problem that we worry about.
A few centrals here and there...not a big deal and it's normal and we shrug our shoulders and move on.

Sounds like you didn't have a large number and they didn't seem to cause any problem with desats or prevent you from actually transitioning into sleep so the doctor isn't concerned.