Narcosis Properties of Different Gases

[pocky21]

So...since O2 isn't narcotic, I can just plumb a line of Dilantin and go do a no deco 250' dive on 100%, right?

 

[gianaameri]

No, it doesn't say that.

http://medspace.mc.duke.edu/sites/default/files/734806.pdf

"CONCLUSION: Impairment of mental function in man produced by exposure to air pressure (8.0 ATA)..."

 

[Dr. Lecter]

From the same study at p. 398:

In recent years there has been increasing evidence that raised pressured of oxygen may cause a depression of the central nervous system, either directly by producing narcosis-like effects similar to those of high pressures of nitrogen and other inert gases [cite omitted], or by potentiating the narcotic action of inert gases [cite omitted]. . . . . This suggests that nitrogen pressure has to be 3 to 4 times greater than that in oxygen pressure and, hence, that oxygen is 3 to 4 times as potent a narcotic as nitrogen.

But you keep thinking you function better at the same depth on oxygen enriched air, kiddo. KFTC.

 

[OkByMe]

Yawn... I think Gianaameri has sucked all of you in... He moves to the right, y'all move to the right, he moves to the left, y'all move to the left... the only thing happening is the grass is getting trampled.

 

[gianaameri]

From the same study at p. 398:



But you keep thinking you function better at the same depth on oxygen enriched air, kiddo. KFTC.

Yes, EAN32 is superior to Air in a cave environment in the 24 to 30 meter range including in respect of narcosis.

This is because O2 is NOT narcotic at recreational diving depths (i.e. N32 at 100').

O2 is NOT narcotic at recreational diving depths because:

1. No evidence exist that it is.
2. For O2 to exert narcotic properties it requires 8 bar of pressure and a pPO2 of 1.65 bar - none of which are encountered on N32 at 100'.

The NSS is right when it writes in the NSS Cave Manual pg. 145:

"For dives deeper than 25 fsw, however, if some of the nitrogen is replaced with oxygen, the no decompression limit is extended and the amount of decompression that must be conducted for any given dive profile is reduced. In addition, the amount of nitrogen narcosis is diminished."

Those who believe the contrary have been unable to demonstrate despite trying hard that at recreational depths O2 is narcotic and had to resort to 8 bars to get some sign (i.e. 10% impairment) of O2 narcosis (and this at 1.65 pPO2 which exceeds the pPO2 of N32 at 100').

Hyperbaric specialists have been WRONG before. Training agencies move from fad to fad for commercial reasons and there is no scientific basis in the current fad that O2 is narcotic using Nitrox at recreational depths.

Maiorca, Mayol, Pellizzari, Ferreiras... and many others have repeatedly shown that reality differs from theory and mathematical models!

I'll be monitoring this thread to see if at some point in the future some new research will become available or will be posted showing that O2 is narcotic at recreational diving depths (at which time I will change my current opinion).

There is nothing further I can add at this point.

I politely request my stalkers who have been following me from the CDG forum to refrain in their pointless denigratory activities (and use their time instead to contribute something meaningful and intelligent to this thread which I will read with interest).

 

[syntaxerrorsix]

 

[dfx]

http://medspace.mc.duke.edu/sites/default/files/734806.pdf

"CONCLUSION: Impairment of mental function in man produced by exposure to air pressure (8.0 ATA)..."

Here's some news for you. You may wanna sit down for them. Are you ready?

It doesn't say anything about how narcotic O2 is at any other depths or ppO2.

It specifically does not say that ppO2 of 1.65, or 8.0 ata air, is any sort of minimum requirement or threshold value at which O2 becomes narcotic.

All it says is that at 1.65, the amount of impairment caused by the narcosis is around 10%. Therefore, the only logical conclusion that can be drawn from it is that as ppO2 increases, narcosis increases, and as ppO2 decreases, narcosis decreases.

A good assumption would be that at double at ppO2, narcosis is doubly strong (which however can't be tested due to oxtox) and that at half the ppO2, narcosis is half as strong.

You, however, claim that narcosis simply vanishes at some lower ppO2 level. You base this theory on... nothing apparently, since there's no evidence supporting it. You also have not been able to come up with any particular ppO2 at which you think narcosis sets in. Unsurprisingly, because there's no evidence suggesting that this is how it works.

Yes, EAN32 is superior to Air in a cave environment in the 24 to 30 meter range including in respect of narcosis.

This is because O2 is NOT narcotic at recreational diving depths (i.e. N32 at 100').

O2 is NOT narcotic at recreational diving depths because:

1. No evidence exist that it is.
2. For O2 to exert narcotic properties it requires 8 bar of pressure and a pPO2 of 1.65 bar - none of which are encountered on N32 at 100'.

Wow, you should be a politician

 

[lanta]

...

This is because O2 is NOT narcotic at recreational diving depths (i.e. N32 at 100').

O2 is NOT narcotic at recreational diving depths because:

1. No evidence exist that it is
...

By extension, black holes are NOT portals into other universes because...NO evidence exists that they are.

Cite a study proving otherwise, gianaameri, and I may reconsider my stance.

 

[gianaameri]

You, however, claim that narcosis simply vanishes at some lower ppO2 level. You base this theory on... nothing apparently, since there's no evidence supporting it. You also have not been able to come up with any particular ppO2 at which you think narcosis sets in. Unsurprisingly, because there's no evidence suggesting that this is how it works.

You are right!

I just found out on Google that depression is now treated with O2 (if Google says so, it must be true!).

Because O2 is 3 to 4 times more narcotic than N, this new study shows that depressed people who are switched to O2 from Air (it is well established O2 is incredibly narcotic) become incredibly happy.

Another pilot study is underway to use O2 as a cheaper replacement for anesthesia gases to drop further the cost of heart transplants in India.

The scientists (they must be on Scubaboard too) believe that increasing O2 and decreasing N increases by multiples the already well known and established narcotic properties of Air (Air contains 0.21% O2 so based on your assessment/logic Air is narcotic which would also explain the physiological processes behind many of the posts in this thread).

 

[ScubaSteve]

Another pilot study is underway to use O2 as a cheaper replacement for anesthesia gases to drop further the cost of heart transplants in India.

Doctor Nick offers more credibility than you seem willing to offer....