Dry Hypoxia Training for Rebreather Divers

[silentbob]

There are many variables. Doing this exercise once could cause someone to falsely feel armed with information when they, in fact, have incomplete data.

Exactly, even doing it three or four times. The falsely armed diver feels more confident, they may weaken their protocols with regards hypoxic gas management on the surface and shallow.

Without any evidence that there is efficacy in this training (the fact that the aviation industry does it is no evidence at all) it is without merit.

 

[anarchista]

We work SO far away from hypoxia that's its almost a non issue in my opinion, except at the surface. Free flowing adv with 10%, surface, waves, foam making it hard to see displays, struggling with attaching a stage... That's a hypoxia mishap looking for a place. Would you recognize it? Not if you've not trained to detect it.

Thank you, I just invented a solution for such a circumstance.

Hyperoxia? Two bad cells and a rig that follows them and you're off to the races.

Bill Stone has a solution for the occasion, others also already exist.

It's presumptive to state what information I have or do not.

You do not have research a large effort.
You do not have the knowledge of pure inert gases and the early signs of hypoxia.
You do not have the knowledge of the impact of high ppN2 the early signs of hypoxia.

Now it is a realistic assessment.
You did not say in the discussion of these problems, talk about them skeptics.

greet rc

 

[anarchista]

So, no, I do not see the value in a diver doing a "hypoxic couch dive" to acquire an incomplete set of data as to what a divers unique personal set of symptoms would be in the event of hypoxia, not when the diver should NEVER be allowing his/her PO2 to come anywhere close to the clutches of hypoxia, at the surface or underwater.

If I had the information, that Dave has studied regions which I am asking. I could make a decision, very worthwhile.
I do not have the information and confidence that the symptoms are easily identifiable: the high effort, breathing pure inert, in high ppN2.

greet rc

 

[paulraymaekers]

If I had the information, that Dave has studied regions which I am asking. I could make a decision, very worthwhile.
I do not have the information and confidence that the symptoms are easily identifiable: the high effort, breathing pure inert, in high ppN2.

greet rc

one comment only: we do not discuss breathing a pure/inert gas
this is completely different from breathing a low/very low PPO2 gas

breathing a pure/inert gas is usually lethal after a few breaths (according to people involved in saturation diving)


added on 19/10/12: I should have be more specific: as far as I heard, breathing pure Helium is usually lethal after a few breaths, and unrecoverable: seems like if the body is refusing to take up oxygen again when you try to 'revive' the victim, after he/her breathed pure helium
(there has been a case of multiple deads in an accident involving saturation divers all breathing pure helium by mistake)

 

[scubasavage]

Interesting topic but cant see the HSE in the UK or HSA in Ireland.

For me, I'd think teaching pO2 monitoring and showing the YouTube videos are a better option... I cant image many new ccr divers just learning their unit being happy doing this test. I think you would also need medical staff on standby if doing these test in a commercial setting.

I had two friend on my Mod 1 try this and also try Co2 breakthrough. They said it was beneficial, but I'd be slow to offer this on my courses.

 

[anarchista]

one comment only: we do not discuss breathing a pure/inert gas
this is completely different from breathing a low/very low PPO2 gas

breathing a pure/inert gas is usually lethal after a few breaths (according to people involved in saturation diving)

I belong to those few people who breathed pure nitrogen, the description is in the discussion. (medical security and was wide monitoring ppO2, ppCO2, respiratory rate, depth of breathing, inhaling negative pressure)
I put this extreme example to show that if something works, it must be in the region of possible hypoxia.

Breathing nitrogen was nice. I'm afraid of this threat.

If the reactions of said Dave are limited to a very specific embodiment, it is not useful training.

greet rc

 

[Dave Sutton]

one comment only: we do not discuss breathing a pure/inert gas
this is completely different from breathing a low/very low PPO2 gas

breathing a pure/inert gas is usually lethal after a few breaths (according to people involved in saturation diving)

This is absolutely true, unrecoverable possiblilty, and death....

This is why professionals only should be discussing "how" to accomplish the training. And why professional level training is the only safe way to accomplish this. That does not mean being a "diving instructor" or "CCR Instructor". This is not a diving or CCR subject: It is a physiology subject that is correctly taught by people with a background in that area. To say that CCR Instructors should possibly consider it... wrong. For existing CCR instructors to say "I do not believe" or "I will not do" or "I am not happy with this" is all correct: They do not (probably) have the education, background, or training to do this. Why should teaching diving give this expertise? They should come to the course as students, especially as Instructors, so that they can speak to their own students with the voice of experience, not the voice of reading what is said in TDI or ANDI book. To teach you should be expert. Being expert is knowing... not reading lessons from a book. Knowlage comes from experience. Why turn away the possibility of knowing more? How can MORE knowlage work against a thinking man? It cannot.

The rationalizations given here for being "against" learning more information are the same ones that my Grandfather used when refusing to wear a seat belt in his car. "I might be trapped by the belt". "I might not be thrown safely clear of the car after I hit a tree", "I might drive more dangerously if I think I am safer"... and these answers are all nonsense. "I think divers might be less attentive to PP02 monitoring after a course like this"..."I think divers might push towards lower PP02's", etc., etc., etc... this is all nonsense. It is rationalization of a decision made without information.

I also understand why people like Paul are concerned with the knowlage being only partial and someone trying it at home and not having things come out right. I agree 100%.


Good point Paul, thanks for making it.

And BTW "Welcome" and it is god to see you here. Your participation is valued and encouraged!



Dave


.

 

[jturner]

I belong to those few people who breathed pure nitrogen, the description is in the discussion. (medical security and was wide monitoring ppO2, ppCO2, respiratory rate, depth of breathing, inhaling negative pressure)
I put this extreme example to show that if something works, it must be in the region of possible hypoxia.

Breathing nitrogen was nice. I'm afraid of this threat.

If the reactions of said Dave are limited to a very specific embodiment, it is not useful training.

greet rc

Are you honestly telling us RC that you have breathed pure 100% nitrogen gas? For how long?

 

[silentbob]

Why turn away the possibility of knowing more? How can MORE knowlage work against a thinking man? It cannot.

Because you are working on the assumption that this "knowledge" is directly translatable between aviation and diving, you are over extending yourself claiming there can be no downside to this.

The rationalizations given here for being "against" learning more information are the same ones that my Grandfather used when refusing to wear a seat belt in his car. "I might be trapped by the belt". "I might not be thrown safely clear of the car after I hit a tree", "I might drive more dangerously if I think I am safer"... and these answers are all nonsense. "I think divers might be less attentive to PP02 monitoring after a course like this"..."I think divers might push towards lower PP02's", etc., etc., etc... this is all nonsense. It is rationalization of a decision made without information.

You really have a thing for strawman fallacies and other ways of misrepresenting what others say Dave. Please don't, you are being disrespectful and it gets very tedious. Perhaps a better analogy would be if your Grandad had a friend who was an aviator. This aviator friend thought parachutes were the best thing in town as they had saved many an aviator. The aviator knew Grandad was a little forgetful sometimes in that he would forget to put his seatbelt on or look where he was going. But instead of concentrating on getting Grandad to pay attention more he tells Grandad to wear a parachute. Grandad might drive over a cliff and have time and the ability to get out of the car and deploy the chute but if he'd just pay attention more....

The question remains. How do you know that the early symptoms of hypoxia will not be often masked by other physiological phenomena?

Without that being answered it seems to me and many others this idea of yours is the equivalent of a homeopathic parachute.

 

[WFO]

The question remains. How do you know that the early symptoms of hypoxia will not be often masked by other physiological phenomena?

You don't, but it's one more string to your bow of possibly avoiding a serious incident, which is enough for me.

 

[Dave Sutton]

^^^ what he said.

It's part of a continuous process of learning and knowlage, absolutely none of which can ever be wasted.

Knowlage is power. Gain every bit possible. Use it wisely.


Dave


.

 

[anarchista]

Are you honestly telling us RC that you have breathed pure 100% nitrogen gas? For how long?

About 12 breaths, sitting without work.
The first 5-6 did not show an increase in depth. The increase in the initial breaths was linear.
It was still comfortable. This is not some secret knowledge that he knows many anesthetists.
So I know that Dave has not been examined this way to hypoxia.

A completely different picture was in a closed circuit without removing CO2 and without supplement oxygen. Then, from the beginning of a rise in deep breaths.
Ogranizm also strongly manifested a high level of ppCO2.

It's part of a continuous process of learning and knowlage, absolutely none of which can ever be wasted.

Knowlage is power. Gain every bit possible. Use it wisely.

Dave Examine the region if it will have symptoms that you know, you have something very valuable.
Without symptoms who placed recognize in the region of possible hypoxia, have little value for the course.
The problem still remains a lot of effort and impact ppN2.
You will still be running away from the response.

The question remains. How do you know that the early symptoms of hypoxia will not be often masked by other physiological phenomena?

Without that being answered it seems to me and many others this idea of yours is the equivalent of a homeopathic parachute.

You see Dave, I'm not alone in doubt.
Customs observation thank "silentbob".

greet rc

 

[silentbob]

You don't, but it's one more string to your bow of possibly avoiding a serious incident, which is enough for me.

How do you know this "string" will have a positive benefit rather than a negative?

I am a Skeptic in all things, this is not to say I believe in nothing but rather that I am not inclined to take claims merely at face value.

This is a good description of Skepticism:

"A skeptic is one who prefers beliefs and conclusions that are reliable and valid to ones that are comforting or convenient, and therefore rigorously and openly applies the methods of science and reason to all empirical claims, especially their own. A skeptic provisionally proportions acceptance of any claim to valid logic and a fair and thorough assessment of available evidence, and studies the pitfalls of human reason and the mechanisms of deception so as to avoid being deceived by others or themselves. Skepticism values method over any particular conclusion."

So with that in mind, how can you predict what the outcome of this "training" will be?

The burden of proof that this is worthwhile and that it will not falsely equip divers lies with those advocating the action.

It seems to me that there is ample evidence that being aware of your PO2 is beneficial. Without evidence that divers are able to reliably self diagnose hypoxia and interrupt the event, the precautionary principle would suggest it is better to reinforce gas management protocols and PO2 monitoring in ourselves and others.

 

[silentbob]

Knowlage is power. Gain every bit possible. Use it wisely.

It's knowledge not knowlage

Use it wisely...

:naughty:

 

[wedivebc]

It's knowledge not knowlage

Use it wisely...

:naughty:

Thank you

 

[liztribe]

Once I filter out all the aviation references, I see a lot of contradicting statements and am not sure what exactly this thread is hoping to accomplish anymore...

conducting optional dry-environment hypoxia training for students. Essentially the question regards the "ethics" for lack of a better term of allowing a closely monitored student to sit on the couch and breathe from an ever-decreasing PP02 loop while doing simple word and math problems until the first signs of hypoxia are noted.

To be clear: This has never been a part of any sanctioned diving training course I have taught. It's always "friends gathered for advanced training".

The rebreather lecture and demonstration "in the living room" takes about an hour.

I am not "literally" suggesting it be done on your couch by an instructor

This has never been a part of any sanctioned diving training course I have taught.

The rebreather lecture and demonstration "in the living room" takes about an hour.

the diving industry leverage the knowlage base already established by the aviation community to develop a synergy in training a suibject that is common to both and to come to some concensus standard by which it might be made available as a sanctioned training event.

What I am advancing is dialog on how this might be done in a more mainstream way as a more normal training event for rebreather divers.

The knowlage is already there, it's just distributed in aviation circles, not diving circles. I'm advocating to change that in rebreather course development. Cross-Pollination of communities, so to speak.

Dave, are you suggesting that you'd like to see this integrated into standard CCR training?

No, far from it.

The actual "couch dive" takes abiout 5 minutes. If you have someone with the knowlage, and a rebreather, you have all that it takes.

For existing CCR instructors to say "I do not believe" or "I will not do" or "I am not happy with this" is all correct: They do not (probably) have the education, background, or training to do this. Why should teaching diving give this expertise?

I can't imagine any rebreather diver not seeing the value in this, thus my poll

This is why professionals only should be discussing "how" to accomplish the training..... This is not a diving or CCR subject

We work SO far away from hypoxia that's its almost a non issue in my opinion

It's 'Pique" BTW... Peaks are reserved for mountains.

BTW, it's knowledge, not knowlage

 

[matt]

Thread seems to be going around in circles.

My answer to the question of a free-flow ADV is flow-stop.

All things considered I'm still of the opinion that hypoxia training isn't high enough up my list of potential improvements to warrant serious investigation. I don't fancy a couch experience nor travelling to a paid experience.

I can tell you that neat helium leads to death - my friend tried it with 100% success. Keep away from it.

Matt.

 

[Mr fish]

Thread seems to be going around in circles.

My answer to the question of a free-flow ADV is flow-stop.

All things considered I'm still of the opinion that hypoxia training isn't high enough up my list of potential improvements to warrant serious investigation. I don't fancy a couch experience nor travelling to a paid experience.

I can tell you that neat helium leads to death - my friend tried it with 100% success. Keep away from it.

Matt.

yep he came to my mind as well

 

[silentbob]

Dave just to try and make it a little clearer, you threw this little aphorism out earlier in the thread. (my annotations)

"The more you know (A), the longer you will live (B)".

Three possibilities here.

A causes B
B causes A
A and B are caused by something else.

Knowing more does not imply higher survivability.

 

[Clare]

Just sticking my admin nose in. Everyone playing nice?