Accumulated 02 following a large number of repetitive Nitrox dives over 3 days.

[rjack321]

PS. speaking about things that can make you go blind...

This thread?

 

[uncfnp]

Interesting. Now that I'm at work and can do better literature searches, I stand corrected: my post #78 should've read "the first sign is severe myopathy?"

PS. speaking about things that can make you go blind...

Myopia. Myopathy is muscle disease and weakness. Muscular dystrophy is one well known example.

You know, sometimes my vision does get blurry with a lot of diving but I think that is more a function of my contacts and canned air.

 

[TrimixToo]

I wouldn't go so far as to say it was the correct decision.

As it turns out, your CNS O2 exposure was likely within limits of different methodology than your computer was using, but you had no way of knowing that at the time because unlike Scubadada, you didn't have another computer you knew was running that calculation. All you knew were three dive computers all were telling you to end the dive.

Scubadada is making an informed decision between two computers running different calculations, one more liberal that the other -- but it was a known calculation, he knows he's within limits on at least one of them and he knows why they differ and what that means. Your choice was between computers you knew were telling you to quit for reasons you didn't fully understand and....the unknown.

Not trying to beat you up, but IMHO, that wasn't a very prudent thing to do. It might be a reasonable thing, going forward, to decide which methodology you believe is best and buy a computer that implements it, but if you don't have it with you, or you aren't calculating CNS halftimes yourself (which is not hard), then best practice is to follow the computer. If I ignore my NDL limits on my computer and find out, only after the fact, that I was within limits using some other algorithm, it doesn't make my decision in the moment a good one. It just means that I was lucky.

Past practice is a fallable guide. CNS hits, like DCS hits aren't that reliably predicted. It's sort of like how many bullets to put in the gun before playing roulette. Plus, unless you were using a different computer, then the fact that it didn't alarm on all your previous trips, and did here, suggests that you were diving more aggressively. And, while I haven't done the calculation, you may have been at or even above recommended whole body limits on the days with a ton of dives, which could have been problematic had you had a DCS hit and needed treatment in a chamber.

Kudos for coming on the board to figure all this out. I guess my one piece of advice, which of course you can take or leave, is that there's always another dive. If my computers were hollering at me to turn the dive, and I wasn't 100% confident that I could safely ignore them, I'd turn the dive and figure it out on the surface.

^^^ Put better than I likely would have.

 

[dmaziuk]

Myopia. Myopathy is muscle disease and weakness. Muscular dystrophy is one well known example.

You know, sometimes my vision does get blurry with a lot of diving but I think that is more a function of my contacts and canned air.

Oops. I guess myopathy is what happens when retinopathy turns into myopia but doesn't go all the way. Bad brain, no cookie.

PS my vision goes blurry from CSR so the word retinopathy is... familiar.

 

[Astran]

Oops. I guess myopathy is what happens when retinopathy turns into myopia but doesn't go all the way. PS my vision goes blurry from CSR so the word retinopathy is... familiar.

Myopia is the medical term for nearsightedness, which millions of people have, and requires glasses to correct distance blur. It is a refractive, not medical condition.

High myopia is associated with large eyes, that are more prone to medical conditions including myopic degeneration and other ocular pathologies.

CSR is fluid under the central retina and is not directly associated with myopia.

 

[dmaziuk]

:sigh: I was typing the word "myopia" but had the word "retinopathy" on my mind. (Plus I was watching my code run on the other screen.) So the word that came out got only half way there.

It's not funny when you explain it.

 

[tursiops]

:sigh: I was typing the word "myopia" but had the word "retinopathy" on my mind. (Plus I was watching my code run on the other screen.) So the word that came out got only half way there.

It's not funny when you explain it.

When you are in a hole, quit digging.

 

[martincohn]

@martincohn Your post being completely off topic- this is about 02 toxicity not "should you dive a computer". Additionally, the question was already asked, and answered earlier. Perhaps next time before you jump into a thread and post an off topic comment, you'll read the thread first and avoid repetitive useless posts, eh?

Well lets see...
The specific word "computer" is mentioned multiple times in the OP. There were additional mentions of specific computers by name.

And then there's that last line...

Can someone please clarify exactly what happened during these dives and exactly what risk we were exposed to by simply disregarding the computer's indications.

But if you feel better after your post then its all good.

You sound like you need to go blow some bubbles...LOL

 

[Astran]

The specific word "computer" is mentioned multiple times in the OP.

So is the word "the". Your point?

 

[tursiops]

So is the word "the". Your point?

OP, you are trying too hard to not own your error. Give it up. You learned from it. You were lucky, this time. Next time you ignore THREE computers saying the same thing, maybe you won't be so lucky.