I need some guidance [TennisTom's therapy thread]

[TennisTom]

Hi Gideon and all,  Here are charts from last night's sleep.  Seems the same patterns of not-normal breathing, which is beginning  to concern me.  I took the mask off to scratch an itch, and apparently fell asleep for a bit with the mask off.  Also, I awoke with a slight headache today.

   

   

Thanks again for all input.

Tom

[TennisTom]

Hi Gideon, others have intimated (as you did) that maybe I have the wrong machine.  I do have another machine that was given to me for no particular reason a couple years ago--before I even knew I'd be a user (but I've had an inkling for a long while).  Its a Resmed AirCurve 10 ASV machine.  I fired it up last night, just to see the difference, and it was dramatically different.  I used it for 5 hours and got an AHI of 1.61.  With the Remed Airsense 11 I've never had a score lower than 7.7 and its usually 12 or 13.

Unlike the '11, where every breath felt forced, this was almost like breathing normally.  Every so often it would give me a burst of air (I assume this happens when it senses I've either stopped breathing or I'm breathing very shallow.  Aside from those bursts, I barely knew I was on a cpap.

I still had a couple hypopneas and some apneas, but it happened amongst some significant leaks.  Can those be discounted?

It looks to me like I have the wrong machine--what do you think?

Here is what it looked like via OSCAR
   

Short breathing segment
   

Leaks and AHIs
   

Many thanks for your kind support.

Tom

[TennisTom]

Just trying to understand how this works: BIPAP machine reduces the pressure on exhalation, so two different pressures, one for inhale, and another for exhale
On regular CPAP its one constant pressure BUT if you activate EPR, you reduce the exhalation pressure by 1, 2 or 3 cmH2O.
Yet, reading through this forum and others, its often noted that using EPR is risky because it can contribute to CAs.
Help, confused.

[Crimson Nape]

The Bi-level machine can cause CAs as well.  One major difference in using an actual bi-level is it has a "Trigger" sensitivity setting that can help reduce the CAs caused by the pressure difference.  The trigger will end EPAP and initiate IPAP pressure at the slightest breath change.  

The CAs are caused by CO₂ washout. This is the caution when using a pressure difference. The upside of a higher IPAP pressure is it will reduce flow limits. It's kind of a double-edged sword, and is a balancing act.

CPAPs are limited to whole number pressure differences up to 3 cm.  The AirCurve (bi-level) can go all the way up to 8 cm difference, in .2 cm increments.

[Sleeprider]

The CPAP model does not report flow limitation, but the flattening and irregularity of the inspiration wave is remarkable. You would do so much better with a bilevel machine that would increase pressure during inspiration to overcome the flow limits. At the same time, you have a very healthy tidal volume and respiratory volume, so although your expend a lot of effort to suck in a breath of air, and inspiration time is relatively long, it will be hard to obtain a bilevel machine, just because the medical and insurance system is so determined to issue the least expensive device shown to be medically necessary.

The ASV is an interesting twist. I'd like to suggest some changes to the settings and see if that takes care of these issues. Your ASV is currently set to default values at EPAP min 4.0, EPAP max 15.0, PS min 3.0 and PS max 15.0. I'd like to see EPAP min 5.0, EPAP max 8.0, PS min 5.0, PS max 10.0. This may help with the obstructive and flow limit aspects of your therapy, and should still stop any central events.

[TennisTom]

Hi Sleeprider, I set the ASV machine to your suggested settings with phenominal results:  AHI score of .54!! Only 4 H's all night and no OAs, no leaks.  Check it out:

   

I also slept longer than I have in a long while, 3 hours 52 minutes.  Prior to last night, I was usually only good for an hour or maybe an hour and a half per session.  Still getting up too often to be rested in the morning, but that is the right direction.

So now I know the CAs can be controlled by the ASVauto feature, but I also read through another post about member "letsrun100", who battled CAs for months but ultimately was able to control them with a regular cpap machine with pretty low pressure, presumably because his CAs were therapy-onset related.  Maybe my CAs are therapy related, also, could that be?  I've been on cpap every night since March 7th.  Thats' just shy of 8 weeks right now.

So I'll use my Airsense 11 cpap 'til my next follow up on May 23rd.  That will give the Doc plenty of data at 15 cmH2O and also show him the data from the 2 nights I used the ASV machine (AHI 1.61 and .54).  I'm sure I'll end up with another study, looking for Centrals.  That's just short of 8 weeks at this point.