Long time CPAP user still fatigued

[Bhante]

My nose also felt plugged

For me that is invariably a sign that my humidity is too high, reduce humidity and it goes away. I need very high humidity otherwise I get problems with my mucosal membranes, but sometimes particular weather conditions lead to higher humidity than expected.

[Bhante]

Take calm [magnesium] and 1mg meletonin, to help fall asleep faster but maybe that's adding to the morning grogginess.

I tried using melatonin at one time, it was a disaster. Just made me extremely groggy; well that's not quite true - it was a long time ago (around 2008) but I think I did sleep more, but felt terrible after. For a short while I tried reducing the dose (manually taking about 1/10th of the capsule!), but ultimately I decided the melatonin wasn't really useful for me.

What I did find helped tremendously at that time was L-Carnitine, which is a precursor for melatonin (but also has other functions in its own right). Are you by any chance vegetarian, or taking relatively little meat? If you take lots of meat you should have enough L-Carnitine, but if you take very little you might easily have a shortage. Having sufficient L-Carnitine is essential for sleep. Another thing you might try is extra biotin which I found essential at the same time as I found L-Carnitine essential. Sounds like you probably need to continue taking the magnesium.

[Bhante]

Notice both tidal vol and leak rate dropped dramatically around june 28. 

Leak rate dropped - probably because the pressure was low. Maybe because the OEM fan was too weak; but in theory as far as I know the Resmed measures pressure supposedly to correct it automatically, so a weak fan ought to be compensated for by ramping up pressure (fan speed). Or maybe because in one of its typical misdemeanors Resmed - before the OEM fan came in - was ramping up pressure causing the high pitched noise and high leak, which was "corrected" by the OEM. Just an "alternative" viewpoint. The new machine doesn't sound like a great success to me - maybe you need to reign it in and clip its wings by tying down maximum pressure?

[enigmatic]

   
   
So, tidal vol is still much better with new machine at around 400 median (low end of my expected wt/ht range 400 to 600). Went back to original titration numbers (no EPR 7/16, purely for experiment dropped a little to 6.8/16).

Although numbers look good (as usual), I'm still waking up pretty lethargic (not tired enough to sleep but eyes alertness very fatigued head pressure).

1) I thought someone here mentioned EPR increases tidal vol. Is this true? Any idea of the relationship offset? I was watching lankylefty video where he said EPR not good because not properly releasing CO2 or something about the mixture O2/CO2 (not debating or anything, just thought to try without, because I think somehow the gas mixtures got screwed up with old machine/blower replacement).
2) Any thoughts on further adjustments given the feedback?

* got cpap chap, nose bridge and inside still itch on occation causing arousals. Using dreamware silicon pillow small with med headpiece. Working on trying to minimize turning surrounding with pillows, edge of bed. Going to bed fairly fast now (compared to 2 hour insomnia onsets before).
*sleep state legend. 0=deep sleep, 1=core sleep, 2 = REM, 3= awake

[SarcasticDave94]

Admitted I've not been on Apnea Board for a while, however I'm sure the belief that EPR is still a good bit of ammo in the CPAP arsenal is still valid. EPR gives you PS (pressure support) from the bilevel like a VAuto and others higher up, without being bilevel.

Similar benefits with more limited control.

Lefty lanky has helpful tips in most cases, however his thoughts on EPR not being useful is something I won't agree with.

[enigmatic]

   

I'm starting to strongly believe it is hypoventilation. Notice in the attached graph of tidal volume, the three red bands indicate lower and upper range (and mean) of normal tidal volume. These are numbers after the brand new apap machine. They were far worse before. I also believe this explains much of the fog, dizziness, lethargy, etc unexplained by good AHI. None of my doctors or sleep doctors ever even looked at any of this - everything was AHI is great, go get checked for depression.

That being said, it looks like the best solution to control tidal volume is iVAP. Now that I know what to look for I've seen some posters discuss this in the past. Can anyone tell what a good machine is and cost (I was already cringing over ASV and can barely find any new iVAP online). Pros/Cons? Would ASV solve the low tidal volume reasonably? Any additional info? thanks.

[SarcasticDave94]

FWIW, ASV stands for Adaptive Servo Ventilator. While it's in the ventilator class, it's also only a sort of ventilator and sort of CPAP, a tweener.

ST-A is what I call the first ventilator within ResMed. It's moreso a ventilator than ASV is. It does iVAPS, ResMed's take on AVAPS and that is a mode the bigger ventilators do as well.

ST-A and ASV are similar priced mostly, and will depend on where you buy. Stellar and Astral will be more. Actual values change constantly.

Besides mode differences, ST-A is a static EPAP, unless ResMed added Auto EPAP (available in Lumis models), ASV Auto has EPAP range. Due to purpose, ASV and ST-A algorithms are acting on different things as I recall. Astral maybe Stellar have auto EPAP.

ResMed ST-A, Stellar 100 and 150, and Astral 100 and 150 are progressively bigger and more powerful ventilators. All have same modes I think, however physical pressures are capped at different values.

Thinking that Astral goes up to 50 IPAP, as example, Stellar at 40. I think ST-A stops at IPAP 30.

Astral and maybe Stellar have 3 different limb circuits got different need setups, 1 of which is a single limb leak equal to a CPAP setup, and can use your current CPAP mask.

Stellar can use a ResMed H4i humidifier that snaps on the front, otherwise Stellar and Astral have need of external humidifiers from ResMed or F&P. Heated hose is another thing, Stellar might support it but Astral is a separate external unit, thinking F&P has that too.

If you're just needing to step into a ventilator class unless you're needing the bigger guns,
ST-A is best bet in some ways. Humidifier and heated hose identical to ASV and lower, smaller unit, pricing close to ASV, same access to clinical menu with familiar setup.

Astral modes as example...

   

ST-A modes as example

   


Probably too much info, but hopefully something was useful.

[Jay51]

Fantastic explanation by Dave.  

In order for ASV to work, you would need both:  1.  A high enough respiratory rate (if your is too low, then ASV simply uses your average respiratory rate to calculate it's respiratory rate).  

2.  You would need a high enough "natural" tidal volume since, again, ASV uses your average tidal volume to calculate it's tidal volume rate.  

ASV uses a rolling average (either 1 minute or 3 minutes) and will tend to keep your natural respiratory rate and natural tidal volume the same.  ASV is contraindicated for hypoventilation patients.  

Dave has explained ST (both S (uses your spontaneous respiratory rate) (and T - gives a timed back up rate), and ST (A) - IVAPS.  IVAPS and AVAPS can increase your natural tidal volume.  Whatever your natural tidal volume is on a particular breath, say it's 300.  If IVAPS is set to 500, then IVAPS or AVAPS will make up the difference with every breath - i.e. - it will add 200 to that particular breath to bring you to 500).  This works with every breath.  If your breath is naturally over 500, then the machine adds zero to that particular breath's tidal volume.  ASV doesn't do this.  ASV will give you the same natural tidal volume you used in the last minute or 3 minutes. 

Cheapest VAPS option would be either the ST (A) or Philips Dreamstation Bipap Avaps.  The Astral and Evo are much more expensive.  And the ST (A) IVAPS data will work with OSCAR.  Philips encrypts the data on this Evo ventilator.  I am not sure if the Dreamstation AVAPS would work with OSCAR.  

I know Dave is waiting on a ventilator right now.

[enigmatic]

@Dave & Jay.  Thanks to both of you for that.

@Jay, you say it will do a 3 min rolling average of your natural tidal volume. How does it determine the natural tidal volume? When I first go to bed it's really high,
then when I fall asleep it rolls off way too low. I would ideally want to target volumes within my ideal BMI tidal volume range, and that's where I read about iVap.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8116389/ paper is here, I just don't have enough experience nor money to sort out the minutia and if ASV could solve my problem, without exactly guessing. Reading your post again, seems like ASV not really going to do much, it looks like it's more about constraining variability in the tidal vol rather than offsetting to desired target/range.

I'm leary of phillips after the black foam incident.

I can't just keep 'trying' machines out of pocket. Especially at the increased costs. I really wish my sleep dr. knew how to get me through this. 
And after all I've been through, I certainly want access to monitor my data and progress, no edf files available equal no way.

It would be great if the lab could freely loan them for a month to try and verify first. Although, he mentioned there's an option to try and buy, I imagine the final price is 
going to be astronomical relative to online vendors. I'm liking the card to cloud options for price but can't find many online.

[Jay51]

With the ASV, it will calculate your tidal volume when you fall asleep (which you say is higher and close to normal).  It would probably stay high for a little bit.  But every  1 minute or 3 minutes it recalculates it; so your tidal volume would eventually start getting lower and lower and lower during the night.  The same thing with your respiratory rate (it is calculated and recalculates continuously during the night).  That is why it is contraindicated for hypoventilation patients.  It can work well for CA's, but not that well for someone that hypoventilates.  It can't continuously, all night, keep tidal volume up in a person who hypoventilates. 

I understand your being leary of Phillips products.  I think they got this Evo right though IMO.  

The most low risk way to approach this IMO is try a used ST (A) with IVAPS, if you want to.  If it doesn't work out, you could probably be able to resell it and recoup some or most of your money.  You could try the sleep study/insurance route; if you have the patience for it.  100% your decision here though Enigmatic.