NITROX for any and all dives?

[tursiops]

Thanks tursiops, that would make more sense. She is not as comfortable in the water but is absolutely fascinated with what she's seeing, so I dive to her comfort level. She's come a long way in 4 years.

Poor breathing can easily let CO2 build up, and that can cause anxiety and headaches. As you get more comfortable, and breathe more slowly and deeply, the CO2 problems go away.

 

[woodcarver]

Yes, and that would be a good description of her progress. Her sac has gone from over 1 in that first trip to about .35 in our last.

 

[MaxBottomtime]

Why make double blind studies when we have Scubaboard instead? I've learned a lot here that is not taught in any nitrox course. The miracle of Enriched Air is the greatest thing since sliced bread. Nitrox not only makes you feel better, less tired or less fatigued, it decreases your gas consumption, turns 80 cu ft tanks into 100s, relieves dry mouth, cures cancer, eliminates DCS and improves your looks. We need to find a way to increase oxygen output from plankton and trees so our atmosphere will improve. I've gone my entire life breathing air. It's time to fix that so we can all be better looking.

I forgot to add reduced narcosis. I read that a lot on Scubaboard as well. Did any of these people read their Nitrox class manuals?

 

[bladder]

I forgot to add reduced narcosis. I read that a lot on Scubaboard as well. Did any of these people read their Nitrox class manuals?

False.

 

[boulderjohn]

I forgot to add reduced narcosis. I read that a lot on Scubaboard as well. Did any of these people read their Nitrox class manuals?

I don’t run into this argument in many scuba board discussions. On the other hand, a recent fairly decent study indicated that there may indeed be a benefit to using Nitrox to limit narcosis.

 

[Storker]

a recent fairly decent study indicated that there may indeed be a benefit to using Nitrox to limit narcosis.

For which there is a plausible hypothesis:
1. Oxygen and nitrogen are equally narcotic
2. Metabolism of oxygen in the tissues reduce its concentration, thus the real concentration is lower than what the fraction would indicate, so the narcotic effect of an increased oxygen concentration is lower than would initially be expected.

As the experience of narcosis is rather situation-dependent, i haven't noticed any clear trend that EAN reduces narcosis for me, I'll continue treating oxygen as just as narcotic as nitrogen. Besides, since nitrogen narcosis usually (at least for me) manifests close to the MOD for common EAN mixes, it won't matter much any way.

 

[dmaziuk]

2. Metabolism of oxygen in the tissues reduce its concentration, thus the real concentration is lower than what the fraction would indicate, so the narcotic effect of an increased oxygen concentration is lower than would initially be expected.

So what you're saying is, it's the oxygen bound to hemoglobin that has no narcotic effect, whereas nitrogen dissolved in the tissues does. You do see a bit of problem there, right?

 

[Storker]

So what you're saying is, it's the oxygen bound to hemoglobin that has no narcotic effect

No, it's not. Please pay attention. What im saying is that I've heard the argument that since O2 is metabolized in the tissues, its partial pressure there might be lower than what one would expect given the P and the FO2 in the breathing gas. And that it seems plausible. Nothing more than that.

Now put that strawman back in the shed, will ya?

 

[boulderjohn]

To summarize----

In the past, standard thinking was that there was no difference between Nitrox and air in terms of narcosis, but nobody really knew for sure because it had never been tested. A recent test (within the last year) was reported on Scubaboard, and it indicated that there might indeed be some advantage (not great) for Nitrox in terms of narcosis.

 

[Dr Simon Mitchell]

Hello,

We just received a large grant from the US Navy Office of Naval Research to study (and hopefully definitively answer) the question of whether oxygen is as narcotic as nitrogen, and by extension, whether there is any related advantage to nitrox. A PhD student starts work on the project next month.

Simon M