[Pressure] Same pressure produced best and worst AHI. BiPAP hasn't been helping.

[winston17]

Hello everyone,

History
I have been using BiPAP every night for the past five months but it hasn't helped to resolve my ongoing fatigue, concentration issues, and poor mood. I was originally diagnosed with UARS and "nonspecific sleep architectural impairment". Only 6% of my total sleep time was REM. My sleep doctor originally recommended APAP 5-20 and after two months of no improvement said "if it's not helping than don't use it" and basically said my fatigue was psychiatric in nature. I stopped using CPAP for 6 months, didn't get any better, and eventually purchased a BiPAP out of frustration. I have done numerous labs, seen many specialists, and have been in therapy and on psychiatric medication for two years. I haven't responded to numerous antidepressants and high dose stimulants and my fatigue hasn't improved.

Current Settings
I have been able to get my 99.5% FL consistently under .1 and recently under .05. My CA seem to remain a problem and my flow rate graph still looks choppy. Trigger is high. It appears to me that I have arousals that aren't marked as events and don't correspond with any leaks or FLs (see image). My flow rate looks good then spikes randomly. 

What Now?
I raised my pressure to 7 Epap 11 Ipap which gave me 0.0 99.5% FL but my flow rate still looked choppy so I raised Ipap to 11.4 which produced many CA's. I lowered it back down to 11 Ipap which gave me even MORE CA's. Where do I go from here? Is my tidal volume low for my (male) height 5'8"? Do you think my sleep could be causing my fatigue or something else? I can post my PSG or zoom in on the flow rate if helpful.

I am feeling desperate so any help is very appreciated. Thank you all!

[staceyburke]

I would move the trigger to very high and see if that limits the centrals. Your centrals are grouped together then none then grouped. IF they were O or H events we would call them positional apnea. The cpap is not like at a sleep lab they a bunch of wires recording and belt around you chest all looking at every aspect of the events and a sleep lab is good at recognizing Centrals but the cpap machine just blows a little air and if the air is returned it obstructive and if it does not return it is a central... NOT a great way to diagnose. So I would also look if what you have is at least partly positional apnea.

If it is not positional the collar is less than 25$ and I think it would be good to check it out.
Positional apnea can NOT be controlled by pressure changes. You have to find out what position you are getting into and cutting off your own airway. Have you changed your sleep position? Sleeping on your back? Using more (or new) pillows? These things can cause positional apnea by chin dropping to your sternum and cutting your airway. Think of it of a kinked hose – nothing can get through – you have to unkink the hose…
IF you can’t make a simple change like changing to a flatter pillow helps then you will need a collar. I have a link to collars in my signature at the bottom of the page. It shows people who are not wearing a collar and the SAME person wearing a collar. There is a huge difference between the two.

[DaveSkvn]

Hi Winston17,

That certainly doesn't look like OSA / UARS to me. One thing I would suggest, that I've been doing for a few weeks, is getting an infrared security webcam off ebay/amazon for $30ish and recording yourself sleeping. It lets you determine which side you are sleeping on when the issues occur.

I am entirely unqualified to say anything about this but any meaningful CA episodes (like yours - i.e. not holding your breath whilst adjusting a pillow) that I've heard about are related to heart issues. It might be that you have something like a leaky heart valve that hates you sleeping on a particular side and results in you being woken up / having to move position. If the events all happen in the one position it would give you something to go on,

Good luck

[PeaceLoveAndPizza]

Quite a bit to unpack there. Note that you are in the fine-tuning stage of CPAP setup, so things move a bit more slowly than the honeymoon period of first receiving it.

• Your flow rate whilst choppy is not that bad. You have some arousals, but they look to be more related to falling asleep in the first chart and to the CA's causing arousals in the second chart.
  
• I think your tidal volume is fine. A bit on the low side, but nothing that would concern me.
  
• Stacey made a good suggestion to try a soft cervical collar and set your trigger to be more sensitive. I suggest going to high to leave some headroom if you need to go to very high.
  
• Post your sleep study with personal data redacted. It never hurts to review things.
  
• Have you tried self-titration? If not consider trying this:
  

Mode VPAPauto
EPAPmin 5
IPAPmax 15
PS 3

I suggest starting with PS=3 for a few nights, then go to PS=4. Once you have a few nights in you can raise EPAPmin to the median and set IPAPmax to the 99.5%.

There is nothing wrong with your settings, other than Stacey's suggestion of trigger=high. Whether the pressure and pressure support is proper for you will require further analysis and testing.

[winston17]

I would move the trigger to very high and see if that limits the centrals.  Your centrals are grouped together then none then grouped.  IF they were O or H events we would call them positional apnea.

I will change my trigger to very high to see if that helps. My PSG only noted one central apnea, therefore these CA are most likely TECSAs or Positional Apneas? There's no way to tell the difference from the flow rate or context? I'm a side sleeper with a relatively flat pillow trying to keep my neck in line with my spine. I will try a collar. Thank you.

[winston17]

I used APAP on my old Airsense 10 (PS 3) and used the method you mentioned of EPAPmin to median and IPAPmax to 99.5% for EPAPmin 4.2 IPAPmax 6 but this didn't adequately resolve FLs or CAs. I eventually got a bilevel and continued to use similar settings but I don't understand the significant nightly variations in FLs, CAs, and RDI given the stable pressures, leak rate, etc. shown in picture 1.

My trigger has been on high for the past month. I will leave it here for now. Do you recommend I redo titration using VPAPauto and your settings?


Given the nightly variability and that I have been at around these pressures for 4 months, could this be evidence of positional CAs? I will try a cervical collar as I cannot find a pattern as to why my number of CAs, FLs, and RDI fluctuates so much. I appreciate your help.

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[*]Post your sleep study with personal data redacted. It never hurts to review things.

[*]

Here is the additional PSG information.

[winston17]

Hey Dave,

I had a PSG done and was diagnosed with UARS with an RDI of 6. I didn't see significant positional variance on RDI  but I only slept on my back and left side. I don't think I have true CSA given I only had 1 central apnea on my PSG. However, I like your idea on the camera which might give me insight on positional CAs marked in OSCAR, thanks.