C02 Retention / Decay times

Drmike · 8th November 2007, 09:49

Quote: (Originally Posted by Dsix36)

How does this help?
This thread is scaring the sh*t out of me

purging the reg will give you very low WOB and help force ventilation. If your panting like a train and losing the battle you have nothing to lose

I would only do this as a very last resort as in life or death because even if it works you may have used up too much oc bail gas anyway....

**Dsix36** · 8th November 2007, 23:07

Quote: (Originally Posted by Drmike)

purging the reg will give you very low WOB and help force ventilation. If your panting like a train and losing the battle you have nothing to lose

I would only do this as a very last resort as in life or death because even if it works you may have used up too much oc bail gas anyway....

OK now it makes a little sense. thanks for the reply Mike. I hope that I never have to do it though!

Simon Mitchell · 9th November 2007, 00:13

Quote: (Originally Posted by Drmike)

purging the reg will give you very low WOB and help force ventilation. If your panting like a train and losing the battle you have nothing to lose

I would only do this as a very last resort as in life or death because even if it works you may have used up too much oc bail gas anyway....

As Mike implies, the only way out of the spiralling crisis we have described earlier is to lower work (which includes the work of breathing) so that less CO2 is produced while ventilation is maintained, thus (hopefully) creating a positive balance of CO2 elimination over production. The work of breathing may be lowered significantly by "mechanically ventilating" yourself using the purge button of the regulator during your inspiration. You should not be pushing it during exhalation. Thus, its not really like "breathing from a free flowing regulator" as has been mentioned by someone above.

Simon M

Simon

Mdemon · 9th November 2007, 08:14

Quote: (Originally Posted by dave t)

A friend of mine (hes very well known so I wont name him) had a massive co2 hit in 20m of water it came on very fast like seconds, he was dragging a 20kg weight across the bottom. (there is some evidence to show that if the po2 is above 1bar or so the initial symptoms of co2 poisoning can be masked) his breathing was so uncontrolled he could not bailout and anyway he was so incapacitated he could not open the valve of his bailout bottle. Fortunately he was right next to the shot and managed to physically drag himself up the line where fast acting surface support rescued him. He told me later that it was about 5 hours before he recovered from the hit!!! In that instance bailing was impossible and a diluent flush if he could have managed one would have been useless.

Dave

My buddy had a carbon-copy hit just like that. Same depths etc.

This post by Iain deserves a second read regarding CO2 and also O2 diving. It confirms what many of us had concluded; that you can learn to identify the onset of hypercapnia. Whilst a lot of us are happy to test our personal CO2 reactions ourselves, I wonder if there is a more controlled, safer we to do it?

I'm highlighting this in particular because I think the sooner you recognise CO2 signs and symptoms, the sooner you can do the things mentioned in this thread to break the CO2 cycle.

(PS I think I've tried the purge thing at depth, and IIRC, on a crappy reg it wasn't as good as hoped. Always worth a try though.)

8th November 2007, 09:49	#91 (permalink)
Drmike Custom Title Allowed! Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,325	Re: C02 Retention / Decay times Quote: (Originally Posted by Dsix36) How does this help? This thread is scaring the sh*t out of me purging the reg will give you very low WOB and help force ventilation. If your panting like a train and losing the battle you have nothing to lose I would only do this as a very last resort as in life or death because even if it works you may have used up too much oc bail gas anyway.... __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment
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8th November 2007, 23:07	#92 (permalink)
Dsix36 Going Down? Current Rebreather/s: Optima Other Rebreather/s: Join Date: Aug 2007 Location: Deerfield Beach, Florida Posts: 1,062	Re: C02 Retention / Decay times Quote: (Originally Posted by Drmike) purging the reg will give you very low WOB and help force ventilation. If your panting like a train and losing the battle you have nothing to lose I would only do this as a very last resort as in life or death because even if it works you may have used up too much oc bail gas anyway.... OK now it makes a little sense. thanks for the reply Mike. I hope that I never have to do it though! __________________ THE MORE THAT I LEARN, THE MORE THAT I STILL NEED TO LEARN!!!!!!
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9th November 2007, 00:13	#93 (permalink)
Simon Mitchell New Member Current Rebreather/s: MK 15.X Other Rebreather/s: Join Date: May 2005 Location: New Zealand Posts: 177	Re: C02 Retention / Decay times Quote: (Originally Posted by Drmike) purging the reg will give you very low WOB and help force ventilation. If your panting like a train and losing the battle you have nothing to lose I would only do this as a very last resort as in life or death because even if it works you may have used up too much oc bail gas anyway.... As Mike implies, the only way out of the spiralling crisis we have described earlier is to lower work (which includes the work of breathing) so that less CO2 is produced while ventilation is maintained, thus (hopefully) creating a positive balance of CO2 elimination over production. The work of breathing may be lowered significantly by "mechanically ventilating" yourself using the purge button of the regulator during your inspiration. You should not be pushing it during exhalation. Thus, its not really like "breathing from a free flowing regulator" as has been mentioned by someone above. Simon M Simon
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9th November 2007, 08:14	#94 (permalink)
Mdemon SiegeEngine II Current Rebreather/s: Inspiration Classic Home Build Other Rebreather/s: Inspiration Classic Home Build Join Date: Feb 2007 Location: SWUK Posts: 1,927	Re: C02 Retention / Decay times Quote: (Originally Posted by dave t) A friend of mine (hes very well known so I wont name him) had a massive co2 hit in 20m of water it came on very fast like seconds, he was dragging a 20kg weight across the bottom. (there is some evidence to show that if the po2 is above 1bar or so the initial symptoms of co2 poisoning can be masked) his breathing was so uncontrolled he could not bailout and anyway he was so incapacitated he could not open the valve of his bailout bottle. Fortunately he was right next to the shot and managed to physically drag himself up the line where fast acting surface support rescued him. He told me later that it was about 5 hours before he recovered from the hit!!! In that instance bailing was impossible and a diluent flush if he could have managed one would have been useless. Dave My buddy had a carbon-copy hit just like that. Same depths etc. This post by Iain deserves a second read regarding CO2 and also O2 diving. It confirms what many of us had concluded; that you can learn to identify the onset of hypercapnia. Whilst a lot of us are happy to test our personal CO2 reactions ourselves, I wonder if there is a more controlled, safer we to do it? I'm highlighting this in particular because I think the sooner you recognise CO2 signs and symptoms, the sooner you can do the things mentioned in this thread to break the CO2 cycle. (PS I think I've tried the purge thing at depth, and IIRC, on a crappy reg it wasn't as good as hoped. Always worth a try though.) __________________ www.southwestmafia.com "small minds talk about people, Average Minds Talk About Events, GREAT MINDS TALK ABOUT IDEAS!" The WRONG Attitude will get you killed. "Once the agenda-monkeys and perfect-worlders have moved on, perhaps we can do some diving?"
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