New oxygen narcosis study (May 2017)

[DevonDiver]

New study turns the O2 narcosis question around 180 degrees... again.

Objective vs. Subjective Evaluation of Cognitive Performance Duri...: Ingenta Connect

"The results suggest that EANx could protect against decreased neuro-cognitive performance induced by inert gas narcosis. It was not possible for blinded divers to identify which gas they were breathing and differences in postdive fatigue between air and EANx diving deserve further investigation".

 

[Scott]

METHODS: Eight volunteers performed two no-decompression dry dives breathing air or EANx for 20 min at 0.4 MPa.

Not a very large sampling.

 

[The Chairman]

Not a very large sampling.

Nothing here that will make me change the way I dive.

 

[DevonDiver]

Hence "suggests", rather than "proves", I guess?

 

[MaxBottomtime]

Before the dives, breathing air, mean time to complete the task was 1795 ms for MathProc and 1905 ms for Ptrail. When arriving at depth MathProc took 1616 ms on air and 1523 ms on EANx, and Ptrail took 1318 ms on air and and 1356 ms on EANx

So they performed better underwater than at the surface? Ptrail was performed faster on air than EANx? I don't think this limited study shows any real results.

 

[The Chairman]

So they performed better underwater

These were "dry dives", which means they were in a chamber. However, they got to practice it first, so of course they were better on their second go around. If they were serious, they would run eight divers backwards. Have them do the test under pressure first and then without pressure. This seems like a relatively easy and inexpensive test to run. As it is, it's next to useless. Again, it won't change the way I dive one bit. You lose IQ points when you put on gear, more points just by splashing and you keep losing them with depth. At some point you're the mental equivalent of a cow as your bovine index approaches one.

 

[rhwestfall]

At some point you're the mental equivalent of a cow as your bovine index approaches one.

I've practiced really hard to not, at the same time, be peeing upstream of where I'm drinking....

 

[Charred]

If they were serious they would post raw data, standard deviations and have executed the experiment with a control so you could understand the baseline for those tests in order to tell if there were changes from the norm. Means alone tell you nothing.

That's really bad science there. I doubt that was peer reviewed. If that came across my desk I'd reject it outright.

That study would likely not even earn a passing grade in a middle school science project because it is so poorly designed.

 

[The Chairman]

If they were serious they would post raw data,

You're only reading the abstract or synopsis of the study. For $30.00 you can get the whole thing which probably includes the raw data. As sketchy as this abstract appears, I'm doing to save my money.

That's really bad science there.

Maybe they were suffering from surface narcosis???

 

[kelemvor]

Really? Surely a 300 millisecond average difference in humans doing anything must be considered insignificant and completely inconclusive.