Central SA / disordered breathing / hypopneas / POTS / air hunger

[Madhi]

Hello

Relevant health stuff (or key words for anyone else searching for these things): Central Sleep Apnea, hypopneas, POTS/dysautonomia, cerebral hypoperfusion, air hunger, breathing pattern disorder

After using CPAP for about a year and a half for central sleep apnea (where hypopneas are my main problem), I have just discovered OSCAR, and it's amazing.  The graphs pick up my disordered breathing so well!

Specialist had me trial CPAP just in case it helped with the CSA, knowing that in most people it doesn't.  Turns out it did actually reduce my hypopneas a bit, so I've been using it for over a year now.  I see a CPAP clinic nurse a few times a year, but she just looks at an automatic summary report that gives her a summary of average numbers.  No one has been looking at my actual daily info!
I'm fascinated by what I'm seeing, and wanted to post my graphs, because it would be interesting to see if anyone has seen other graphs that look like mine.  Or if people with a similar health profile to mine might see something similar in their own data.


Quick explainer for those interested:
When I'm awake I have hyperpnea (excessive deep breaths), as a result of cerebral hypoperfusion (reduced blood flow to brain) and air hunger.
This is the body's natural response to reduced blood flow to the brain.  Chemoreceptors in the neck mistake it for hypocapnia (reduced c02), so the body responds with hyperventilation or hyperpnea, and constricting cerebral blood vessels, which just makes it worse of course.  Air hunger means every waking minute I feel like I'm suffocating and can't get enough air even though technically I am.

To the graphs:
I have included 4 graphs as example.  3 of them are pretty normal and average for me (AHI of 8.27, 9.59, and 10.69).  One of them was a bad night (AHI 18.69) just for comparison.
The AHI 9.59 night I'll attach to another post below accompanied by a zoomed in section.

I find it interesting that it picks up hypopneas when I'm awake around the same rate as when I'm asleep.  I'm not surprised by this, as I often find myself holding my breath and have to remember to keep breathing.  It's validating to actually see it.

Because of my hyperpnea (excessive deep breathing), it's really obvious when I fall asleep lol.  Just look at the Tidal Volume, Resp Rate, Minute Vent, Inspiration Time and Expiration Time.  They all have sudden and drastic changes all at once.  Once asleep, my body starts breathing really shallow in comparison to when I'm awake!


Question:  Does this look like possible 'positional' hypopneas?  I've been reading a bunch of posts and sometimes see comments about that.

[Madhi]

On this example night (AHI 9.59) from a few nights ago, I have also selected and screenshotted the 30 minute window where I fell asleep, where the sudden change in breathing occurs right in the middle.
Here are some of the changes just in that 30 minute period from the graph.

MY TIDAL VOLUME
(Calculated ideal tidal volume from apneaboard wiki gave me a range of 359-480 ml/kg)


My awake range is super high, which I'm not surprised by, given I have hyperpnea.  Sleeping range seems a bit low though.

Awake: 450-1018
Asleep: 250-320  


MY INSPIRATION TIME

Awake: 1.7-6.6 sec  (excessive, but again not surprised)
Asleep: 1-2.1 sec

-----------

This has all motivated me to get another referral to see the sleep/respiratory specialist again, because I think there's more to talk about...

[Jay51]

Your tidal volume appears to be the most concerning thing IMO.  I have used several ventilators during sleep.  A machine that can "assure" a certain "x" tidal volume with every breath has helped even out my breathing at night (tidal volume, respiratory rate, minute ventilation, etc.).  

Machines with "back up" rates can trigger a person to breathe when their respiratory rate gets too low.  You rate overall, judged by my OSCAR median seem to be ok.  This is just a thought for the future.  

Discuss these above issues + take some OSCAR charts to your next appointment.  

Here is the reading on positional apnea that might help you some with all the H's:   

• 5.3Positional Apnea                                                                                                                                                                                              Things like lowering pillow height, side sleeping vs. back sleeping (with something under chin to keep it from tucking), and even using a soft cervical collar could help this.  
  

[SarcasticDave94]

Any chance you know what any sleep study tables of event type and count were telling the doctor? Asking because of the Central Apnea you referred to. Not much of the CA in these OSCAR charts.

[Sleeprider]

I'd like to see several zoomed images of the flow rate at a resolution of 3-4 minutes so the flow wave is clearly visible. I can assure you that for an individual with hypopnea and CA events, the Philips CPAPs seem to produce much higher event rates than Resmed which has more tools to work with like EPR, and with the Vauto, Ti min, Ti max and trigger and cycle controls. The purpose of seeing the zooms is to get an idea of the inspiratory flow morphology, particularly flow limitation. FWIW, if you move to ASV, the slow deep breathing while awake is going to be disruptive to the targeting of respiration rate and volume. If you can consciously attempt to moderate that with a higher, shallower respiration rate, that might be helpful. Your explanation of the variable breathing is interesting, but unless you have some assessment of blood profusion, I think it may be more likely some form of loop gain. https://www.apneaboard.com/wiki/index.ph...entilation

[Madhi]

Hi, here are a few flow rate zooms from the most recent graph posted above.
The first one is from when I'm awake, as I thought it would be interesting to compare.
The other 3 zooms have been all added into the one image for convenience.

Meanwhile, I will try to dig up my previous sleep studies.  When I do I shall post an update in case they can shed a light on things.
I recall being told that I have more hypopneas than apneas, and my readings leaned more towards central sleep apnea than obstructive.  (Althought my ENT once suggested I might have UARS.) They didn't really know what was going on with me because my sleep studies are weird, so CSA or something like that was suggested as the best idea they could come up with.

---------

Btw regarding the cerebral hypoperfusion, this is common in people with POTS unfortunately.  I had a brain SPECT done last year to confirm it.  Even when lying down the scan showed several areas of my brain were getting reduced blood flow.  It's even worse when I'm upright.
There have been some interesting studies showing reduced brain blood flow in POTS triggers hyperventilation/hyperpnea and tachycardia, which in turn can lead to hypocapnia, which triggers more hyperventilation (a vicious cycle huh).  Recent studies have shown C02 therapy (breathing in lots of carbon dioxide) can improve the blood flow as well as the hyperventilation, but afaik this isn't yet an actual available treatment...
Unfortunately this is such a recent area of study, so most sleep/respiratory specialists I might ever see won't know anything about POTS related breathing issues.

With the hyperventilation/hyperpnea, I have seen respiratory physiotherapists in the past to help me manage my disordered breathing.  It's practically impossible to stop doing it, so there isn't much I can do but focus on proper diaphragmatic breathing.

[SeePak]

Hi Madhi.

Your comment, "Chemoreceptors in the neck mistake it for hypocapnia (reduced c02), so the body responds with hyperventilation or hyperpnea, and constricting cerebral blood vessels, which just makes it worse of course."

Not sure if you mis stated something here?

If your neck is sensing Low CO2, that should make you breathe less?

I am currently following Patrick McKeown Oxygen Advantage which promotes nose breathing ALWAYS, and this on its own helps to balance CO2 and Oxygen delivery to blood and cells.

Air hunger, when CO2 goes up in lungs, is a psychological feeling that can be tolerated with breathing exercises.


And i can definitely say, they work!

I will add more, want to get this response to you first.

[Madhi]

Hi SeePark, yes you're right, I realised after posting that I worded that part badly but there was no edit option for me to fix it. 
Should have said hypercapnia, not hypocapnia.  (Hypocapnia can be the *result*.)

Luckily I already exclusively nose breathe, when awake and asleep.  (I have an extremely dry mouth, and my teeth are so sensitive just inhaling through my mouth is painful, so I seem to always instinctually lock my jaw shut to avoid all this.)

I'm happy to hear more on this though.  I've tried to learn about this stuff, and have seen a respiratory physio before, but there might be some knowledge gaps there.

[Sleeprider]

We don't have any tools to recruit from the Philips CPAP pro to smooth out this respiration. I'm pretty certain a Resmed Aircurve Vauto would be a good solution to smooth out the rough looking inspiratory flow with pressure support. Have you ever tried higher pressure or C-Flex at 2?

[SeePak]

https://www.apneaboard.com/forums/Thread-VCOM-Bi-Level

Madhi, check out VCOM......A device installed into hose of machine.

Designed to lower Peak Inspiratory Flow Rates, which will help with your Hyperventilation .

Working nicely for myself and others, check out the link!

Your pressure is low, would be increased using VCOM to maybe 8, good starting point possibly.

Agree with sleeprider and probably others, you have a low pressure setting, just need more history/details from you to see what is best way going forward here.

I think with some of these details, you will get a clear idea of what your needs for a PAP machine .

I too had low tolerance for air hunger: Now i love it !