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[Treatment] AHI starts very low increases a lot during nite - Printable Version

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AHI starts very low increases a lot during nite - ricknfli - 12-17-2016

Hello,

I have noticed an unusual pattern to my apnea episodes. They are rare in the first 1-3 hours, then become much more frequent in the last half or so of my sleep time. My nightly AHI tends to run 8-14 no matter what pressures I try. My pulmonologist does not know why the apneas increase later in the night. Does anyone have a reason for this effect?

Background: Almost all of my apneas are central. I do not have congestive heart failure, use drugs that typically would cause this. I do not have Cheyne-Stokes breathing and I am not at high altitude.

I am overweight though. BMI 34.9 Estimated body fat 44%.

I have used the ResMed for about one year. I've been on CPAP for about thirty years. The pressures that work best are highly unusual: I know: IPAP 11 cm H20, EPAP 10 cm H20. Pressure support of Zero. I have had a night where AHI was as low as 3 with this setting, but that is very rare.

I have a Sleepyhead view on IMGUR. If you will PM me I will send the link. Since this is my first post, I am not allowed to post a link.

I would appreciate your feedback.

Thanks much!

I would appreciate feedback.

Thanks much!


RE: AHI starts very low increases a lot during nite - DeepBreathing - 12-18-2016

G'day ricknfli, welcome to Apnea Board.

With your settings like that, your machine is probably just operating like a straight CPAP. Normally for central apnea the required treatment is an ASV machine, which is somewhat more sophisticated (and expensive) than your VAuto. You might want to discuss that option with your doc.

As for having more apneas later in the night, I don't think that is uncommon - it used to happen to me before I got my treatment dialled in. I think it just relates to the various stages of sleep.


RE: AHI starts very low increases a lot during nite - E.W. - 12-18-2016

To a lesser degree mine shows that pattern too. That is in my first hour to hour and 1/2 my AHI is usually between 0 and 2 but for the remainder of the night it usually shows 3 to 6. I have also noticed something different if I fast for a day the AHI goes rather hi. On the other hand if I go to bed with a full stomach my AHI seems to be better. I realy hate that because eating right before bed is bad for my diabetes.


RE: AHI starts very low increases a lot during nite - mcsheltie - 12-18-2016

From what I have read this could be related to REM sleep. Which happens more often later in the night. Looking at my sleep study I have more OAs during REM sleep than any other time.

If you use a wider pressure setting does your AHI increase?


RE: AHI starts very low increases a lot during nite - ricknfli - 12-18-2016

(12-18-2016, 05:18 AM)DeepBreathing Wrote: G'day ricknfli, welcome to Apnea Board.

With your settings like that, your machine is probably just operating like a straight CPAP. Normally for central apnea the required treatment is an ASV machine, which is somewhat more sophisticated (and expensive) than your VAuto. You might want to discuss that option with your doc.

As for having more apneas later in the night, I don't think that is uncommon - it used to happen to me before I got my treatment dialled in. I think it just relates to the various stages of sleep.

Thanks for replying DeepBreathingThanks

Yes, the ASV machine is something I need to talk to my new sleep Dr about. The last sleep doctor said the ASV machine might not help much. I would like a second opinion.

I also a read a note last night where someone said the Central events that lasted 10 seconds or less could be normal for me. I plan to see if SleepyHead has a setting that would let me modify the threshhold for detecting Open Airway events.

And yes, I think my REM sleep is a lot more frequent later in the night.

Thanks again!



RE: AHI starts very low increases a lot during nite - DeepBreathing - 12-19-2016

Quote:I plan to see if SleepyHead has a setting that would let me modify the threshold for detecting Open Airway events.

Not specifically for open airway event, but #SleepyHead does allow users to set modified thresholds. Go to File > Preferences > CPAP > Custom CPAP User Event Flagging. From there you can set various options for flow restriction and duration thresholds. It will probably take a bit of trial and error to get the outputs you want.



RE: AHI starts very low increases a lot during nite - ricknfli - 12-19-2016

Many multiple thank yous!! ThanksThanksThanks

Thank you DeepBreathing It appears that SleepyHead has many times the capability than me. I tried changing the User event flagging without much success. It appears that the software would be a PhD Sleep physiologist's tool. However, just checking the events manually showed many, many central apneas > 11 seconds, so I have my answer.

Thanks mcsheltie - To reply to you, Yes, a wider pressure setting increases my AHI.

Thanks E.W. - I feel like I sleep better with a full stomach tooEat-popcorn, but it aggravates my reflux problem.

And yes, I think the increased AHI does correspond to increased REM sleep.

I guess I will check out the ASV idea with the new sleep doctor and report back later. Smile

Thanks much to everyone for your help! Sleep-well


RE: AHI starts very low increases a lot during nite - PaulaO2 - 12-19-2016

Is your diagnosis purely CSA? Or do you also have OSA?

If your pulmologist said he/she didn't know why the AHI does this, then you need to drop that person like a hot rock and go elsewhere.

If your CI (central index) is consistently over 5, you have the wrong machine.
If you have OSA and it is being treated by the current machine, great! But you still have the wrong machine.
If you do not have OSA and your high AHI is all central events, you have the wrong machine.




RE: AHI starts very low increases a lot during nite - ricknfli - 12-21-2016

Hi PaulaO2,

Thanks for your reply. I have the name of another pulmonologist. I'll see how he can help.

I do have a very few OSA. I'll have to find the last test. I think the last lab said, Oh you have CSA so you need a BiPAP. Oh well. This new machine has given me feedback of what is actually happening at night. Maybe Medicare will pay for an ASV machine. I bought the BiPAP machine since I was falling asleep while at work and when driving. Those symptoms are better, but not gone.

Thanks again for your reply!

Rick


RE: AHI starts very low increases a lot during nite - richb - 12-21-2016

Hi ricjinfly. Welcome to the Apnea Board. You are going to be able to post links to some Sleepyhead screenshots by now. Consider that if your primary concern is Central Apnea you don't want to reduce what Sleepyhead sees of it. For insurance purposes (Medicare) you are first going to have to fail at traditional CPAP/BiPAP in order to qualify for an ASV machine. ASV machines are expensive and insurance requires lots of documentation to show that your present machine doesn't work. Your present machine is probably aggravating whatever your Central Apnea issues really are. Post those screenshots including some 7 to 10 minute snippets around scored events and during non-scored breathing. We can help with advice regarding reducing your pressures to see if you can reduce the Central type events (Clear Airway/Central Apneas, Central Hypopneas, Periodic Breathing and Cheyne Stokes type Respiration not associated with Congestive Heart Failure). If you really do have Central apnea with a few OSA events you are not going to be able to get rid of the Centrals with fine tuning. You will be able to see at what pressure OSA events start to appear and at what pressure you can reduce full blown Centrals to Hypopnea events. These would eventually be your starting settings with an ASV machine.

Rich