Stubborn Centrals

[kevrx]

Hello all,

I am impressed with the amount of knowledge I see passed on through this forum.  I am hoping someone may be able to shed some light for me on a few things.  Does Ipap or Epap contribute more to pressure sensitive central apneas?  I have had EPR set to 1, but I think I like it set to 2 better to help with my air flow.  I often have nasal congestion, and a higher pressure support seems to help keep my nasal passages open better; although it may also be higher humidity that helps.  When my machine was set up, EPR was set to 1, but the min/max was not set to compensate so I think my EPAP drops too low and I desat.  It seems that IPAP pressures over 8.6 or so increase centrals, but I am not sure if I should look at EPAP or IPAP pressures since I have had EPR at 1, 2 or 3.  I was titrated in my sleep study to 8 with no EPR and I had the fewest incidents at a pressure of 7 and 8, but I like the idea of having and adjustable machine to compensate for various circumstance.  The pressure  may be going to high, or I may need to lower the EPR.  I did have EPR set to 3 and at first I felt great, but then one night I felt like I over ventilated and did not feel well the next day.  I did not realize till yesterday that I needed to raise my levels to compensate for EPR and I think a min EPAP of 7 helps with my o2 level.  I have had settings between 6 and 12 with various EPR and my centrals vary greatly.  My oa ahi is normally in the 1's, hypopnia < 1, and centrals between 3 and 8.  Sometimes the centrals come in clusters it seems as I am waking up in the morning or if I am being woken up by my wife or cat.  Others are by themselves and may be pressure related.  When I had my first sleep study, I had more centrals and mixed than obstructive, but I am known to snore quite a bit and for at least one nostril to be totally blocked.  I tried setting the machine to CPAP mode with a pressure of 8 with and without 1 EPR, and I still had a central ahi of 4 to 4.5 with a total ahi of 5.7 and 6.6.  I know I have tried a lot of things and been accross the board.  My total AHI seems to vary between 5 and 10 no matter what I do.  Does anyone have any suggestions on a path I might take to improved breathing at night?

Thank you,
kevrx

[Gideon]

Welcome to the forum.

You said you were titrated to 8 cmw.  This means your CPAP pressure should be 8+EPR as your exhale pressure is what supports obstructive events.
for a range, I would use 8-12 EPR=2 full time.

You talk about centrals.  The question is what is the cause of the centrals?
Were centrals present on your diagnostic study?
On your titration study?

It would help if you posted redacted, we don't need personal info, full copies, not just the summaries, of both studies.  Yes the tables and charts.
Also OSCAR daily charts of a recent typical night.


Now speaking in generalities and not your specific case.
It is not uncommon to have the CPAP actually cause centrals, thus the need to see if they are pre-existing.  What happens is the CPAP improves the breathing efficiency with improved oxygen exchange and improved CO2 clearing out.  The later is very important as the CO2 level in the blood is the major driver for breathing.  What happens is the CO2 is washed out of the blood to a level below your apneic threshold resulting in a central apnea.  With CPAP or BiLevel machines, we reduce EPR or pressure support to increase the amount of CO2 in the blood and eliminate the centrals.  We also do that as a test to see if this is the case.  If this is the case sometimes time, getting 'used to' the new CO2 levels reduces the apnea over 2-3 months.

Yes, increased pressure may also cause centrals but the EPR is a more important factor.

Or you may have Idiopathic Central Apneas, in which case an ASV may be in your future.  

Your current machine is not capable of treating central apnea, we can avoid it and maintain a balance between central and obstructive apnea.

[kevrx]

I forgot to mention that I was diagnosed with PLM and I have been given clonazepam 0.5 mg at night and it seems to help quite well.  Here is my latest chart.  I actually felt pretty good today, but my AHI was high.  My pulse ox was average 95% with a low of 89, but this is only from a garmin watch.  The average is often around 89-90.  If it is in the 94-95 range, I feel pretty good.  Here is my most recent Oscar chart.

   

[SarcasticDave94]

I agree with what bonjour is saying. Best practice is to have your detailed sleep study for 2 reasons. You need this in your personal health file and you can post the redacted of personal info copy here for us to help decipher what kind of Central and other events you're having. The basic CA types we may see are predominant/pre-existing, treatment emergent, and idiopathic. Each can require different actions to treat.

I'd suggest doing as bonjour mentions. Get the sleep study report in a multi-paged detailed format, redact your personal info, and post it here within this thread. We can help decode it.

[Gideon]

Kevin read my above post, I had to edit it.

Seeing your daily charts I suggest setting EPR = 0 or off to see if we can lower the centrals.

[kevrx]

Thank you for the information.  Are you then suggesting a pressure of 6-10 with EPR off?  Here are my studies.

Thank you,

kevrx


  SST.pdf (Size: 816.19 KB / Downloads: 36)

  TT.pdf (Size: 984.77 KB / Downloads: 31)

[Sleeprider]

Complex apnea with moderate PLM. You have had central apnea before and during CPAP. bonjour is on the right path with simplified pressure without EPR, but only time will tell if it is effective. Your centrals were present all along at twice (or more) the frequence of obstructive events, and I suspect their resolution will require ASV. There is no CPAP or bilevel setting to resolve them, it requires adaptive servo ventilation.

[kevrx]

Thank you all for your help and thoughts on my situation.  After I gathered all of my information last night, I forgot to put the card back into my machine.  With no EPR, I struggled greatly with nasal congestion and trying to get to sleep.  I raised my ramp pressure twice, then turned it off.  I had my pressure set from 7-10.  I was able to breath a little better at the pressure of 7.  At 4:30 I woke up with my mouth dry and nasal passages completely blocked.  Central AHI was only 2 and total was around 3-4 (I can't remember exactly).  It said the pressure was 9.8.  I changed my pressure to 9-12 with EPR 2 and eventually my nasal passages opened up, but I wasn't really able to sleep more.  Central ahi went up to 2.6 and total ahi 3.2.  I did not suffer from nasal congestion at during either sleep study, but at home, it has been refractory to steroid sprays, antihistamine sprays, antihistamines, singulair, and nasal rinses.  The only thing that has kept them open is pressure support of 2 or more.  Even at lower pressures, while on the ramp ei 6 with EPR 2, I still stay congestion free.  I am including an Oscar picture from the other day when I had EPR set to 2 all night; however, I had not adjusted the pressure up by 2 as I should have.  Also, one day I had EPR set to 3 pressure 7-11 and ended with a central ahi of 2.9 with total 4.7 and I felt great the next day; however, the next night, centrals were ahi 8.21 and total 10.38.  Subsequently, I felt over ventilated when I tried EPR 3 again at a pressure of 8-12.  I did notice that during my titration study, I had few events on a pressure of 7 and 9.  Does anyone think keeping an EPR of 2 and a set pressure at 10, or between 9 and 10 may help decrease some of the centrals?   Alternatively, is it possible my body may adjust some to and EPR 2 with pressure 9-12?  I breath and sleep so much better with EPR 2, it just increases the centrals.  Any other thoughts? 

Thank you, 

Kevin

   

[Sleeprider]

Those results look more encouaging with EPR than I would have anticipaated. I wonder why we are only seeing the EPAP pressure?

[SarcasticDave94]

Not as bad on the data results as I'd have expected while using EPR. It will be interesting what tomorrow's results show. CA are notorious for being consistently inconsistent.