The cerebrovascular response to carbon dioxide in humans

[Violeta]

https://pubmed.ncbi.nlm.nih.gov/21521758/

Carbon dioxide (CO2) increases cerebral blood flow and arterial blood pressure. Cerebral blood flow increases not only due to the vasodilating effect of CO2 but also because of the increased perfusion pressure after autoregulation is exhausted.

Our objective was to measure the responses of both middle cerebral artery velocity (MCAv) and mean arterial blood pressure (MAP) to CO2 in human subjects using Duffin-type isoxic rebreathing tests.

Do you think this means that CO2 from rebreathing would be helpful for those of us with low blood pressure?

Also, since:
CO2 is produced during during the Krebs cycle (also known as the citric acid cycle or TCA cycle).

maybe the cause of needing to rebreathe or in some way take exongenous CO2 is because of TCA cycle inability to produce adequate amounts.

 

[Violeta]

I just found this, posted by someone that I follow on Twitter (X).

https://www.healthrising.org/blog/2...autoimmunity-co2-bad-reflexes-next-diagnosis/

The kicker was that giving the POTS patients carbon dioxide during the tilt test normalized the blood flows to their brains, and stopped their tachycardia (rapid heart beats) and their hyperventilation. (For some reason they did not suggest patients start breathing carbon dioxide.)

From the study + the Healthrising article, I am thinking the CO2 reduces hypertension and at the same time allows blood flow to the brain. (reduces hypoperfusion) But I'm not sure, if anyone sees an error in my thinking, let me know.

 

[sb4]

Shouldn't be too hard to try if you have a paper bag or similar handy. I remember trying something similar a few years back but it just made me feel out of breath and a bit stressed but I might try it again.

My thinking is with POTS the body is deliberately vasoconstricting to help poor blood flow. Most things that cause vasodilation in me lead to worse POTS symptoms. POTS patients do vary massively though.

 

[Violeta]

Shouldn't be too hard to try if you have a paper bag or similar handy. I remember trying something similar a few years back but it just made me feel out of breath and a bit stressed but I might try it again.

My thinking is with POTS the body is deliberately vasoconstricting to help poor blood flow. Most things that cause vasodilation in me lead to worse POTS symptoms. POTS patients do vary massively though.

Yes, I am trying the paper bag breathing. Also thinking about the Krebs cycle, and although I already take B complex, I am going back to taking extra B5. I can't handle much B3. But do you know how viruses mess up the Krebs cycle.

 

[Violeta]

It looks like the CO2 would be more helpful for those with hypertension, and I have hypotension.

Maybe I should look for something else for hypoperfusion. I don't know, it's 12:45 (in the afternoon!) and I think my brain is shutting down.

 

[kushami]

I noticed some more research on this topic for POTS and NOH:

https://research.ucalgary.ca/partic...cardia-syndrome-pots-feel-better-reb20-0135-0

https://research.ucalgary.ca/partic...hostatic-hypotension-feel-better-reb20-1322-0

If you are diagnosed with either of these and can make it to the University of Calgary, the studies are open as of today (26 Oct 2024) and you could enquire about taking part.

 

[kushami]

If I read rightly, carbon dioxide levels in the blood tend to mostly affect cerebral vasoconstriction and vasodilation, not the rest of the body, at least in the context of the changes being discussed in the papers above.

In POTS, the problems with lack of vasoconstriction / too much vasodilation are thought to be in the lower body (also maybe the extremities).

So that may be why dilating the cerebral arteries could be helpful (to allow more blood to flow into the brain) but whole-body vasodilation could be unhelpful (as the blood would tend to pool even more in the abdomen and legs and not reach the head due to gravity).

I think.

 

[Violeta]

If I read rightly, carbon dioxide levels in the blood tend to mostly affect cerebral vasoconstriction and vasodilation, not the rest of the body, at least in the context of the changes being discussed in the papers above.

In POTS, the problems with lack of vasoconstriction / too much vasodilation are thought to be in the lower body (also maybe the extremities).

So that may be why dilating the cerebral arteries could be helpful (to allow more blood to flow into the brain) but whole-body vasodilation could be unhelpful (as the blood would tend to pool even more in the abdomen and legs and not reach the head due to gravity).

I think.

Yes, that makes sense. That would be great if CO2 accomplishes that. Let me see if the paper says how it does that.

Thanks for bringing me back to this. Let me look at that study again.

 

[Violeta]

@Nord Wolf , did you see this thread?

 

[Violeta]

Shouldn't be too hard to try if you have a paper bag or similar handy. I remember trying something similar a few years back but it just made me feel out of breath and a bit stressed but I might try it again.

My thinking is with POTS the body is deliberately vasoconstricting to help poor blood flow. Most things that cause vasodilation in me lead to worse POTS symptoms. POTS patients do vary massively though.

I do try this at times, but only when lying down. I will try it while standing up.

I wonder if carbonated drinks work better. Although I don't always drink them, I crave carbonated drinks. I will also try lemon juice plus sodium bicarbonate today.

 

[sb4]

I do try this at times, but only when lying down. I will try it while standing up.

I wonder if carbonated drinks work better. Although I don't always drink them, I crave carbonated drinks. I will also try lemon juice plus sodium bicarbonate today.

I drink a lot of carbonated beverages too. I think it helps digestion by lower stomach PH. I don't know if I crave them but I definitely prefer them over plain drinks. So you might be on to something.

 

[kushami]

I remember there is a thread with info from a member who has experimented quite a bit with breathing CO2, but I can’t find it again.

 

[Hip]

I remember there is a thread with info from a member who has experimented quite a bit with breathing CO2, but I can’t find it again.

This post gives details of the technique of breathing CO2 for cerebral vasodilation purposes. I find it reduces brain fog a bit for about 4 hours after.

 

[Nord Wolf]

I just saw this thread. Though interesting, my issues with cerebral blood flow are selective within regions of the brain rather than the entire brain. Also, the issue is too much blood flow throughout most of the brain, but a lack of in sections like the left cerebellum, mid brain and amygdala. Therefore, all vasodilating medications, herbs, and supplements lead to severe and debilitating headaches within two days that continue to worsen so long as I continue taking the aggravator… caused by excessive vasodilation in the brain.

I also do not have low blood pressure, nor high. Of course, I am on a beta-blocker, but even before that, the high blood pressure issues were short-lived spikes upon rising due to PoTS. Even when the BP would decrease to normal levels, the heartrate would continue rising. Metoprolol at 75 mg twice per day takes care of those issues. But the cerebral blood flow continues to be complicated.

Though I have heard great results with athletes breathing CO2 during training, the short spells that I have tried it before medicating for PoTS, I never noticed a beneficial difference. For me, breathing O2 seems to do a lot more.

 

[Oliver3]

If I read rightly, carbon dioxide levels in the blood tend to mostly affect cerebral vasoconstriction and vasodilation, not the rest of the body, at least in the context of the changes being discussed in the papers above.

In POTS, the problems with lack of vasoconstriction / too much vasodilation are thought to be in the lower body (also maybe the extremities).

So that may be why dilating the cerebral arteries could be helpful (to allow more blood to flow into the brain) but whole-body vasodilation could be unhelpful (as the blood would tend to pool even more in the abdomen and legs and not reach the head due to gravity).

I think.

I've been practicing buteyko for a long time. The whole principle is to change the sensors in the medulla oblongata . The more c02 your body can adjust to, according to buteyko, means the more oxygen can be delivered to tissue throughout the body by means of the bohr effect. There are probably other mechanisms at work. But that was his principle idea.
It's a whole body adjustment.
I've seen reports of free divers who go into remission from autoimmune disease by breath hold against.
Just anecdotal.
One thing that's definitely happened is my long term thrush disappeared overnight

My hallucinating stopped. It was only mild but it stopped.
The thrush went forever...nothing has worked for years and apart a day years ago, it's never come back.
Perhaps it helps stem cell release from the bone marrow too..God knows but the effects are definitely systemic

 

[kushami]

Here’s a recent lecture on hyperventilation in POTS (may be of interest more broadly):

The first segment (about 25 mins), with Dr Jacquie Baker, deals with the topic of hyperventilation, carbon dioxide and oxygen.

The second segment, with Dr Satish Raj, seems to cover the usual information on treating POTS, so you don’t need to watch that part necessarily.

Here is the full paper describing their work:
https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/39297140/

I am sorry, but I haven’t got the energy at the moment to watch the lecture or read the paper so I can’t give a summary.