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Effects of high CO2?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.

naiad

Apnea Carp
Supporter
Oct 11, 2003
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Does anyone know what are the effects of high CO2, as would happen during statics without hyperventilation, CO2 tables, and hard dynamic or depth training?

The immediate effects are obvious (contractions, urge to breathe, lactic acid buildup) but are there any long-term physiological effects?

Lucia
 
I am also very interested in getting an answer to this, as I train without hyperventilation, many contractions and much Co2
 
Trying to rescue this thread...

The only effect I have noticed is that I hold my breath a lot more when resting, and even when I am asleep. It's a sort of general disinclination to breathe. :D :hmm
 
Acutely, very high CO2 levels will progressively cause CO2 narcosis, then shock and finally organ failure and death.

Chronic elevated CO2 levels will cause changes in blood biochemistry, mainly elevation of bicarbonate levels, to compensate for the blood acidosis. It will also cause blunting of the breathing reflex.
 
I've always wondered about the validity of CO2 tables as a mechanism to train CO2 tolerance but having hooked myself up to a pulse oximeter this morning I'm now convinced. I did a table of 8 breathholds the last three having 30secs rest, 15secs rest and 15secs rest and my SAO2 did not fall below 95%. The last four holds were quite unpleasant (CO2) with the last one having 1:30 of contractions but not falling below 95% SAO2.....looks like CO2 tolerance training to me!
 
Is it possible to get acutely high co2 levels while doing no warm up, no breatheup breathholds? With 3 minutes of contractions?
 
kingohyes said:
Is it possible to get acutely high co2 levels while doing no warm up, no breatheup breathholds? With 3 minutes of contractions?

You'll probably only get narced in the worst case. But if you breathe oxygen before your static and really go for it, then there is a real danger of co2 poisoning.
 
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I have experienced extreme CO2 narcosis bordering on CO2 blackout while doing a CO2 table which took me over 10% CO2. This CO2 table was simply successive breath-holds with just one breath in between. Near the end I would get contractions 5 seconds after the inhale and continue for 2 minutes, exhale, inhale, get contractions within 5 seconds after inhaling, and so on.

Several times I went over 10% CO2 and each time I got narcosis, similar to the CO2 narcosis I would get on 80m+ dives.

Dizziness, wooziness, confusion, altered perception, and a sense that I'm losing grip on reality and it feels as though blackout is imminent.

In all these cases my O2 on the oximeters were in safe levels (>80%).

Further during these extreme CO2 tables I would start to get 'yogic' side effects (spontaneous mula bandha & jalandhara, strange feelings of energy in my spine, etc...)
 
Thanks Eric - very useful. That answers my question.

Lucia
 
Just wondering about oximeters and such are they way out there in price ? where do you get them etc, are their personal ones as oppsed to commercial ones etc ?
 
The fingertip portable models such as the "nonin onyx", "spo 5500" and "BCI DIGIT" range from 200-300e I guess...

A little googling should bring plenty of online stores. Ebay and such are good places

They're fun toys, but so far I haven't found any real use for one after the novelty of "wow, look at the saturation drop" wears off. For one, they're horrible unreliable on low saturations, your body will tell the saturation more reliably. With strong vasoconstriction, you might not get a reading at all...The only really useful purpose for one I can think of is SAT training or similar activities...

And of course, keeping with the subject, they tell you nothing about CO2 levels...
 
Last edited:
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You need a Pulse Oxy with a earlobe sensor, luckily for us the vasoconstriction on a breathold doesn't stop blood going to the brain. :)
Tried it with a friends Pulse Oxy and on moderately long breatholds finger sensors just drop out. But it worked great with an earlobe sensor, you can also use the disposable types on your ear.


Cheers,
Wal
 
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Thanks people,
Will do a search on them was also wondering about the meters you use for VO2 max etc I know they are generally hooked up to a pc and a threadmill so I presume they are only commercially available but was just wondering, I think they would be in sports clinics etc but don,t have any near here. Cheers
 
The forehead sensor is the best type of sensor. Ear lobe sensors often don't work well during vasoconstriction either; I have tried them.

Finger tip sensors work very well, even in low saturations & vasoconstriction, but ONLY if the oximeter has Masimo SET signal extraction. For this reason I strongly recommend the Masimo Radical oximeter, the most accurate oximeter available.

It is very accurate on the fingertip even down into the SaO2 < 40% range with vasoconstriction. It is very useful to judge the 'samba SaO2' threshold (i.e. at what SaO2 does the samba occur). In that sense, changing the breathe-up can change the samba SaO2 threshold.

The main use for the oximeter is to calculate your theoretical time without pushing it all the way. For example, I often do a 4'30" static with packing, taking just 2 breaths beforehand, and the saturation at 4'30" can predict my maximum static time within about 15 seconds of accuracy. For example to go over 8'00" I need to be at more than 94% at 4'30" (this being the minimum saturation value after breathing has resumed).

Using this method, whenever I need to go to a competition, I do 4'30" tests every day, especially on the morning of the competition. Thus, I know my best-case-scenario limit for that day even before I arrive at the site.

The oximeter also allows you to debug your breathe-up. The best method is to do your normal breathe-up and then just do a full exhale static and watch your saturation at the 2'00" mark.

The oximeter also allowed me to discover that using a nose clip truly affects my static. My saturations at all times are noticeably lower when using a nose clip. I assume that without the nose clip small amounts of air enter the sinuses and directly exchange O2 with the blood in the sinus cavitiies.
 
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Eric,
What would you guess would be the effect of wearing a mask on saturations. Would it be like the static, or more like what you found with the nose clip on?
Could have quite an effect on a diver's performance at a meet!
Howard
 
Re: Effects of high CO2? Nose

efattah said:
The oximeter also allowed me to discover that using a nose clip truly affects my static. My saturations at all times are noticeably lower when using a nose clip. I assume that without the nose clip small amounts of air enter the sinuses and directly exchange O2 with the blood in the sinus cavitiies.

Or if you take your last inhale through the nose there are some Nitrogen bacteria(?) living in the sinuses that are added to the last breath which helps the O2 uptake. Alveoli that "feels" the N are more acceptible to opening up and letting through O2.

So I heard and so I have experienced it.

Sebastian
Sweden
http://www.fridykning.se/nordicdeep
 
Re: Effects of high CO2? Nose

cebaztian said:
Or if you take your last inhale through the nose there are some Nitrogen bacteria(?) living in the sinuses that are added to the last breath which helps the O2 uptake. Alveoli that "feels" the N are more acceptible to opening up and letting through O2.

So I heard and so I have experienced it.

Sebastian
Sweden
http://www.fridykning.se/nordicdeep

Eric F. had mentioned that air could enter the sinuses while during a dry static breathold (without noseplug), and possibly passively deliver O2 to blood in the sinus cavity, without being breathed into the lungs.

I suggest that the sinuses (holes in sinus bones) have not much blood vessels capable of O2 exchange AFAIK, however the nasal cavity does, and may have some (tiny?) gas exchange. Sebastian mentions Nitrogen in sinuses, AFAIK, humming (pronouncing hmmm or hnnnn) greatly increases Nitric Oxide (NO) in the sinuses. This NO is anti-biotic (kills airborne bacteria and viruses) in the nasal cavity. I'm now trying to find if NO production (by humming) in sinuses might reduce DCS (bends) after a dive (and if ancient divers a million years ago used it while diving for clams etc.). Just Speculating. DDeden
 
Re: Effects of high CO2? Nose

wet said:
I suggest that the sinuses (holes in sinus bones) have not much blood vessels capable of O2 exchange AFAIK, however the nasal cavity does, and may have some (tiny?) gas exchange.

I have wondered also about gas exchange in the nasal passages and even the back of the throat at the base of the spine. In a yogic manner, I have concentrated on breathholding by taking very little, tiny, rapid breaths into the nose only. It's more imagining a small breath than actually taking a breath- if that makes sense. This type of breathing does not involve the lungs. The muscles used are located in the back of the nose and the very upper throat. Because only very small of air enters the nose, sinuses, and the upper throat, energy expenditure must be minimized. It's like playing dead in a bear attack. I feel that long periods in this dormant state are possible by imagining breathing in this manner. Just another idea.....

Peace,
Glen
 
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