High Central AI on Resmed sleep report

If this topic has been broached before I apologize. I did a search for it and was unable to find a satisfactory explanation for my results.

Admittedly I have not been the most compliant APAP user despite being a physician. I'm trying to change that.

Despite being diagnosed a year ago and being an irregular user there is one trend I've noticed from the reports that bothers me. When I look at the report a night, a week or a month the majority of my AIs are labelled as central.

Unfortunately I don't have my sleep report readily on hand. I do know my AHI was approximately 13. So I'm trying to acquire another copy of it but I read it and I was diagnosed was plain old vanilla OSA--not Central or mixed complex.

Is there some confounding factor here to account for the machine interpreting my AIs as central? It is quite possible I am opening my mouth. I have allergic rhinitis and use fluticasone daily. I also know I'm a restless sleeper. I tend to toss and turn, sleep in odd positions and rarely sleep on my back.

I'm questing whether or not to get a full face mask to at least rule out in mouth breathing.

I suppose my old medical student hypochondriac is rearing it's head...I know how serious central sleep apnea is and I should it be the case that I have it I want to treat it properly.

Thank you for any advice or feedback you can give me.

You said you don't have your report 'on hand', but if it's at home, can you post it (using e.g. Photobucket) from there? It would certainly help, but at least if you can get tell us the leak rates averaged over a couple of nights, and a few of the other parameters (off the screen prn), we could maybe guess at things.

So how high is the AHI now when you do use the machine and how much of that AHI is the Central index?
How come you are admittedly not the best compliant cpap user? Spend much time on the machine and not being able to go to sleep or stay asleep?

The machine can and will flag awake/semi awake breathing irregularities as some sort of event and typically a central. So if you are seeing centrals flagged in close proximity to known awake times on the machine then it is possible that the centrals are related to awake/semi awake breathing.
Also it is normal to have a few sleep onset (sleep stage transition) centrals that are the real deal and normally they don't present a problem unless they are present in huge numbers or significantly impact sleep as in they keep kicking you out of sleep back to the awake/semi awake stage so that you don't get the needed deeper sleep.

These cpap machines don't know if we are asleep or not so they just flag the related disruption in air flow as they sense what it might be. When awake our breathing is much more irregular with pauses that we don't realize we are doing and the machine can flag these pauses by mistake from our perspective but not from its perspective. It just calls them like it sees them and we have to decide if what it sees is worthy or worry or not. Kinda hard to do sometimes because we can't always identify when we for sure was asleep or not ourselves. Sometimes we can spot asleep breathing by the change in breathing flow rate on the graphs if we zoom in to a breath by breath level but even then it isn't always cut and dry easy to spot.

Finally...it is possible for some people to develop centrals in response to cpap pressures when they didn't really have many or any to mention on the diagnostic sleep study. Sometimes the cpap pressures can be fine tuned to where the obstructive apneas are effectively dealt with and yet keep the centrals from happening in numbers that are problematic. This would be Complex Sleep Apnea and this doesn't happen often. Sometimes CompSA will resolve with a bit of time on cpap...like maybe 6 months or so. Sometimes it doesn't and a different machine is needed. Centrals aren't something that we need to go into panic mode immediately and start imagining all sorts of horrible things.
First we figure out if the number of them is a problem and/or are they creating a problem with sleep architecture or O2 levels and then consider the options available to help reduce them if need be but if they aren't a problem we shrug our shoulders and move on. Awake centrals...we shrug our shoulders and move on.

Pugsy wrote:So how high is the AHI now when you do use the machine and how much of that AHI is the Central index?
How come you are admittedly not the best compliant cpap user? Spend much time on the machine and not being able to go to sleep or stay asleep?

The machine can and will flag awake/semi awake breathing irregularities as some sort of event and typically a central. So if you are seeing centrals flagged in close proximity to known awake times on the machine then it is possible that the centrals are related to awake/semi awake breathing.
Also it is normal to have a few sleep onset (sleep stage transition) centrals that are the real deal and normally they don't present a problem unless they are present in huge numbers or significantly impact sleep as in they keep kicking you out of sleep back to the awake/semi awake stage so that you don't get the needed deeper sleep.

These cpap machines don't know if we are asleep or not so they just flag the related disruption in air flow as they sense what it might be. When awake our breathing is much more irregular with pauses that we don't realize we are doing and the machine can flag these pauses by mistake from our perspective but not from its perspective. It just calls them like it sees them and we have to decide if what it sees is worthy or worry or not. Kinda hard to do sometimes because we can't always identify when we for sure was asleep or not ourselves. Sometimes we can spot asleep breathing by the change in breathing flow rate on the graphs if we zoom in to a breath by breath level but even then it isn't always cut and dry easy to spot.

Finally...it is possible for some people to develop centrals in response to cpap pressures when they didn't really have many or any to mention on the diagnostic sleep study. Sometimes the cpap pressures can be fine tuned to where the obstructive apneas are effectively dealt with and yet keep the centrals from happening in numbers that are problematic. This would be Complex Sleep Apnea and this doesn't happen often. Sometimes CompSA will resolve with a bit of time on cpap...like maybe 6 months or so. Sometimes it doesn't and a different machine is needed. Centrals aren't something that we need to go into panic mode immediately and start imagining all sorts of horrible things.
First we figure out if the number of them is a problem and/or are they creating a problem with sleep architecture or O2 levels and then consider the options available to help reduce them if need be but if they aren't a problem we shrug our shoulders and move on. Awake centrals...we shrug our shoulders and move on.

Thank you for the explanation Pugsy.

My AHI tends to hover around 4-6.5. And it would appear a large portion (approximately 90%) of those events are centrals according to the reports for 1 day and 1 week.

I really don't have a good reason why I haven't been compliant. I'll give you my excuses. I typically listen to medical audiobooks before I fall asleep (poor sleep hygiene I know) and I'll wait to put the mask on and before I know it I'm asleep.

Secondly, in the short term sometimes I feel better when using my CPAP. Sometimes it seems to actually make me sleep and feel worse. And other times, like last night, It makes me feel a qualitatively different kind of tired. For as long as I can remember I've never woke up and felt well rested. This morning I woke and felt less of that "I just want to roll back over and sleep another hour" and just more of this background tiredness. It still seems to resolve after approximately 4 hours...like my circadian rhythms are shifted...

Luckily I do not have trouble falling asleep with the mask on. At times it does seem like I might have a little more difficult staying asleep but not to the degree that I could be certain these events are result of it.

So I recognize that it's unrealistic to expect something I've likely been dealing with for the last decade or so to resolved after a few nights of use. And I know as a physician who myself gets annoyed with patient noncompliance that it is completely hypocritical for me to not use my CPAP as Rx'd.

I suppose I am more motivated now because I'm about to start residency and be working 80 hours a week. That will light a fire under your posterior when nothing else will....

Again it is very possible these are awake irregularities as I've always been a "deep" sleeper who people could wake up in the middle of the night, have a conversation with, bring it up the next morning and I'll have no recollection of it.

Julie,

I'm not familiar with the software I have and if I could use a USB to get photos of the report or if I should just use my Iphone to take some shots of the report?

As soon as I get a copy of my original sleep study I'll scan it and post it.

Whatever software you are using you can just grab a screen shot of the detailed report and post that screen shot image link in some place like Photobucket.
Explained in this thread along with examples.
Screen shot thread viewtopic.php?f=1&t=81072&p=737779#p737779

somnolentdoc wrote:My AHI tends to hover around 4-6.5. And it would appear a large portion (approximately 90%) of those events are centrals according to the reports for 1 day and 1 week.

It would be nice to see a typical detailed report to get a feel for what you are seeing.

Couple of questions that need specific answers as best you can.
1..Do you spend much time awake when using the mask and machine? Need this to have any idea if we can pooh pooh off a few of your centrals as being awake centrals.

2..Do you ever wake up and remove the mask and go back to sleep? Bad, bad habit to start if you are doing that. Guess which sleep the body remembers? How many hours of sleep using the mask and machine do you average? How many hours without mask do you average...okay..that's multiple questions in 1 but they all fit together.


But if your centrals...if they happen to be the real deal centrals and you are having 4 or 5 every hour all night long...it is possible that the centrals are numerous enough and if prolonged can cause a drop in O2. If this happens then your sleep quality could very well be negatively impacted by the centrals (assuming you didn't have them on diagnostic study) if they are a result of cpap pressure itself. Lots of IFS...so need more information before hitting the panic button.

I do understand the typical medical hypochondriac thing...everything we read about we get.
And because we know we do...we never know for sure how much credibility we need to place on things we see or feel now.

4 to 5 centrals per hour if related to cpap pressure for some reason (i.e CompSA) or if they are all sleep onset centrals...might be enough to explain why you think you might actually feel worse on cpap than without it. I can't say for sure but it's possible.
Of course it is also possible that you simply aren't doing the good sleep hygiene things and aren't getting enough sleep and for sure not enough quality sleep.
5 centrals per hour average is worthy of a worry as that technically meets criteria for central sleep apnea if they are for sure occurring in sleep.

Pugsy wrote:Whatever software you are using you can just grab a screen shot of the detailed report and post that screen shot image link in some place like Photobucket.
Explained in this thread along with examples.
Screen shot thread viewtopic.php?f=1&t=81072&p=737779#p737779

somnolentdoc wrote:My AHI tends to hover around 4-6.5. And it would appear a large portion (approximately 90%) of those events are centrals according to the reports for 1 day and 1 week.

It would be nice to see a typical detailed report to get a feel for what you are seeing.

Couple of questions that need specific answers as best you can.
1..Do you spend much time awake when using the mask and machine? Need this to have any idea if we can pooh pooh off a few of your centrals as being awake centrals.

2..Do you ever wake up and remove the mask and go back to sleep? Bad, bad habit to start if you are doing that. Guess which sleep the body remembers? How many hours of sleep using the mask and machine do you average? How many hours without mask do you average...okay..that's multiple questions in 1 but they all fit together.


But if your centrals...if they happen to be the real deal centrals and you are having 4 or 5 every hour all night long...it is possible that the centrals are numerous enough and if prolonged can cause a drop in O2. If this happens then your sleep quality could very well be negatively impacted by the centrals (assuming you didn't have them on diagnostic study) if they are a result of cpap pressure itself. Lots of IFS...so need more information before hitting the panic button.

I do understand the typical medical hypochondriac thing...everything we read about we get.
And because we know we do...we never know for sure how much credibility we need to place on things we see or feel now.

4 to 5 centrals per hour if related to cpap pressure for some reason (i.e CompSA) or if they are all sleep onset centrals...might be enough to explain why you think you might actually feel worse on cpap than without it. I can't say for sure but it's possible.
Of course it is also possible that you simply aren't doing the good sleep hygiene things and aren't getting enough sleep and for sure not enough quality sleep.
5 centrals per hour average is worthy of a worry as that technically meets criteria for central sleep apnea if they are for sure occurring in sleep.

I downloaded Sleepyhead. I don't know what I'm supposed to do to get the information off of the CPAP and on to my mac so I can post an image.

1). I typically spend almost no time prior to falling asleep with the mask on. That's one of the main reasons I'm not as compliant as I should be. I wait until I am about to fall asleep. I am stopping this all together. From now on I'm put the mask on as soon as I go to bed. And no more audiobooks at night.

My sleep patterns are such that I typically sleep sound for the first 2/3rds of the night then I'll wake up about 3 hours prior to rising, fall back asleep and then maybe do this one more time. Obviously if I could get the graphical representation of this from the CPAP it would help pin this down as the source of the central AIs.

2). Yes I've done this in the past but not recently. In the past few months when I do wake up and take the mask off. I'm done. I get up.

If anything I sometimes do the opposite. I fall asleep, wake up in the middle of the night, and put the mask on. Then i'll get maybe 3-4 hours with the hose on. This happens maybe twice a month.

Surprisingly I average a lot of sleep with the mask on. Last night was 8 1/2 hours. So it would seem 7-8 hours.

It's interesting. I really REALLY need that study I know. At the time I didn't take a huge interesting in it. I think we spent all of 1/3 of a lecture on OSA in medical school. I knew I needed to research it but i didn't have the time and didn't take the initiative. Now that I have a month and a half off I'm going full throttle.

What actually made me pull the trigger and get a sleep study in the first place was going to my PCP and noticing that although I had woke up 45 minutes ago my pulse ox reading was in the high 80s. I reasoned I must be having sleep disordered breathing to see that degree of desat after being awake for that long. Since the brain is a sentinel organ for hypoxia I figured that must be the explanation for my lack of energy in the morning.

So right now I am getting enough sleep. I wake when I feel like it. My sleep hygiene is poor. At some point in medical school I developed the bad habit of listening to study material as I fell asleep. It's become an ingrained habit but I suspect it's time to rip the band-aid off.

So I'm not the most tech savvy individual is there I link for figuring how to get the data off of the CPAP to my computer?

Thanks again for your help.

I don't have a Mac so I can't help with the direct steps involved with a Mac because I don't know the navigation process involved or the terminology.

The basic import navigation is point to the root drive where the SD card sits...don't attempt to go into the folder on the SD card as that's going to far. SleepyHead looks in the root drive for a SD card and knows to look for more than one kind.

I don't know how much of the import/download for Macs information is current here...it should be close though
http://sourceforge.net/apps/mediawiki/s ... sers_Guide
but give it a shot and if you get stumped come back with where you are stumped at and one of the Mac users will chime in with more specific help.

When you get a chance you need to get a hold of that diagnostic sleep study to see if you had any centrals noted then.
And if you had an in lab titration for pressure...any centrals noted then.
If you don't lay away tossing and turning with lots of time awake on the machine then we can pretty much rule out awake centrals and if you don't awaken often during the night and generally sleep fairly soundly..then we can rule out tossing and turning hold your breath centrals.

Great.

I installed sleepyhead, figured out where the SD card is on the S9 and where the SD card slot is on my macbook.

I contacted the sleep center via email and hopefully I'll have it soon.

I'm going to attempt to move the data to sleepyhead and take some screenshots. Hopefully I'll have them posted within an hour.

So as you can see my AHI crescendos at about 5am.

Not sure if it fully explains the clear AIs but this seems to correlate with what I'd just told you. I do have this tendency to wake up briefly and then fall back asleep 2-3 hours before I get out of bed...

I meant to tell you that we only needed the stuff on the left side like you have it and these graphs on the right
Events
Flow Rate
Pressure
Leak
Flow limitations if they are rather active and while yours isn't horribly active it is more active than mine.
You can turn off AHI and Mask pressure graphs in Preferences/Graphs by removing the check mark.
This will allow leak and maybe FL graph to move up so you only have to do one screen shot. That other stuff really isn't needed at this time.
So in the future to save yourself some work you might do that.

You really need to get that original diagnostic sleep study report to see the status of centrals then. Did you have these then or did they just pop up now?
Did you have an in lab titration or did they send you home with the APAP to let the machine decide pressure needs?
Your OAs aren't anything to worry about and I suspect the machine is responding to flow limitations when you see the increases in pressure.

Oh...here's my Flow limitation graph. Yours isn't horribly horrible as I have seen much worse but you do have a lot more FLs showing up than I do...and this is one of my "worse" ones.

Pugsy,

Honestly I can't remember these being on the study. I searched my file cabinet high and low for that report but everything is a mess right now. I'm getting ready to move up to Michigan here in 2 weeks.

I didn't do any lab titration test. There wasn't even any follow up. My PCP is a family friend who trusts me to make 90% of my own health decisions. I'm not convinced that's a good thing since its well known doctors make the worst patients.

So they pretty much let me decide to purchase an APAP and that was it. My sleep doc is one of those entrepreneurs with sleep centers in multiple states. So was pretty much given enough rope to hang myself.

Anyway, I'll be sure to give you the quick and dirty info from now on

I'm hoping to have a copy of that report by tomorrow. d

Yeah, I know about doctor's not making the greatest of patients and they don't always practice what they preach.

I ask a lot of questions to try to get a sense of what is going on. If this report above is a typical report and you say you rarely wake once you go to sleep then if this were my typical report I would also be concerned but I wouldn't be in panic mode regarding the number of centrals I was seeing.

Now I am NOT saying that you have Complex Sleep Apnea but from what you describe...it is a bit suspicious for it. This would be assuming that you didn't have many centrals on that diagnostic sleep study...so bear that in mind. If you had these centrals on the diagnostic sleep study then that's a whole different ball game.
I don't know how much you know about Complex Sleep Apnea but this video gives a good down to earth easy to understand how and why
https://www.youtube.com/watch?v=CU-XTcf ... e=youtu.be
If you had done the in lab titration study if these centrals were related to CPAP pressure itself then it most likely would have shown up at that time but what you did with getting the APAP and self titrating really wasn't that unusual. The number of people who develop centrals as a result of cpap therapy itself is a relatively low % like 10% or so depending on which study you read so the bulk of the people do quite well with letting the machine set the pressures and one goes from there. In fact in some places that way is the normal way to do it and then if there is a problem then they bring the person in for an in lab titration.

Clinically I don't know how significant your numbers really are. The fact that you aren't improving and say you feel worse when using the machine gives me cause for concern. Meaning while not horribly horrible they could be impacting your sleep quality and/or even O2 levels depending on how long those centrals are lasting. To see the duration in SleepyHead click on the Events tab and then the Central category and you will see all the centrals you had and the time you had them and the number in parentheses by each event is duration of event in seconds. They have to be 10 seconds long at least to earn a flag and while we can easily hold our breath for 10 seconds and it not be a problem if you start doing that a whole bunch of times back to back it can cause a drop in O2.

People often associate pressure related centrals to high pressures but in truth they can happen at any pressure even a little pressure like 5 cm but as pressures increase they can be made worse.

So what to do...again taking some liberties with what might be going on assuming no centrals of importance on the diagnostic study and assuming this looks sort of like a mild CompSA situation.
When you look at your reports....are the bulk of them like this one above with nothing going on much for the first 60 to 90 minutes and then as the pressure goes up the centrals start to increase?
If you want to experiment...you might try cpap mode at 6 cm pressure and see what happens both with the OAs and the centrals.
Sometimes there is a fine line with CompSA where the centrals don't emerge and OAs are well controlled. Maybe you are one of those people.
Sometimes people who do have CompSA will have it go away after a period of time on the cpap machine....from what I have read..takes months though.
Sometimes people need a different machine.

The pressure increases seem to sort of correlate to maybe REM stage sleep where it is common to need more pressure in response to collapse of the airway. My own OSA is REM stage sleep much worse. That and supine sleeping are well known culprits. As you know we have the most REM in those wee hours of the morning before we wake up.

I can't help but wonder if a mild CompSA issue is going on here and if it were me I would try the simplest thing first just to see what happens...that being don't let the machine increase the pressure so much just to see if the centrals reduce in numbers and cross my fingers that the OAs didn't go wild.

I also think that the doctor needs to be made aware of the situation. Maybe not immediately right this very minute but after you have seen the diagnostic sleep study report and maybe tried a lower pressure to see what happens.
Now the sleep doctor might be okay with what is going on here and willing to give it time ...if that's what's going on here. The docs get the final say so and if your AHI was 10 with 90 % being centrals that would be more exciting than 5 or 6...but there's too many to pooh pooh off unless someone who knows a lot more than me wants to pooh pooh them off.

Again I don't know that is what is going on here but my gut says there is a chance that CompSA may be going on here so I prefer to be cautious and assume it is until proven different. Never hurts to be extra careful. Using APAP mode isn't always the best thing to do with CompSA unless we use a tiny range...like 1 to 2 cm and barely use enough to keep the OAs under control.

If your diagnostic sleep study said you had 90% centrals then I wore my fingers out typing all this for nothing and we get to have a different discussion.

Okay I went to my PCP and retrieved the report. I was way off on a lot of the info.

Moderate OSA with AHI of 23.6 events/hr
Total apnea index 5.5/hr
hypopnea index 18.1/hr

I also have poor sleep architecture
REM latency 226.0 minutes
Sleep efficiency 69.5%

sleep was severely fragmented 66 arousals and 36.2/hr
9.3 Respiratory related arousals and 26.9 spontaneous

Mean baseline O2 sat 91.9% with 5.9 min below 88% low 02 is 84%

Titrated to 11 cm H20 w/o supplemental 02 AHI was 6.5/hr mean 02 was 94.6 %

Official diagnosis is Moderate OSA

no mention of central events however the Respiratory Events graph shows a smattering of central apnea events.

Apparently it's my fault since I missed the part where he recommend a C-Flex at a setting of 3.

They had my put on the CPAP at 1:18 and it appears to me there are more central events after initating the CPAP. Every cluster after the first one is with the CPAP on.