Narcosis??

[Al Mialkovsky]

There is still one question I have, or better yet, one scenerio I am always wondering about and that is.. how can you tell that you have had any level of narcosis during or after a dive? I understand what factors bring on this condition, but I am curious as to some of your personal experiances with this, and how you knew or what you think were the causes leading to the condition.

Nitrogen Narcosis is caused by a high partial pressure of nitrogen. It goes away by reducing the partial pressure by ascending. It is never there after a dive.

 

[DennisW]

I have halucinated due to Nitrogen Narcosis. Saw my wife swim through the superstructure of the Duane when she just wasn't there. She declined to penetrate and waited for the group at the line. When I didn't see her later, I actually retraced my dive back through the Duane and "found" her at the line as I got back to the group. Walter was tripple ticked off at me and rightly so. This happened years ago, but I will never forget. I have also felt uneasy and paranoid. When this happens, I will ascend 20 feet or so and wait until I feel normal again. Then I'll resume the dive.

 

[fisherdvm]

I ask this because I attempt to dive by the book on every dive I make, paying very close attention to my tables and my ascent time and safety stops, but some times I will experiance a light headedness feeling during and for a short time after, the dive.
.

I wonder if you are confusing decompression sickness with nitrogen narcosis.

I think nitrogen narcosis is relatively independent of decompression sickness.

Narcosis occurs at depth, usually greater than 60 ft, when the partial pressure of nitrogen exert a "narcotic" effect on your brain, causing it to work abnormally. You are slower to think, respond, and make logical decision. You are behaving like your are on drug. Some people have low tolerance for nitrogen, and can not do deep dives, or should avoid deep dives.

Decompression sickness is due to the dissolved nitrogen in your blood stream. The longer you stay in the water, the more nitrogen will dissolve in your blood stream. This dissolved nitrogen will form bubbles, just like the bubbles in your soda pop. The bubbles will plug up blood vessels and damage your nerves, cause pain in your joints, and cause sensation in your skin.

Obeying the dive tables, safety stop, and adequate surface intervals will prevent decompression sickness.

Avoiding diving deep will prevent nitrogen narcosis. My guess is, everyone will have some degree of nitrogen narcosis at greater than 60 ft, and it can be demonstrated objectively by cognative testing.

 

[nereas]

At 105 fsw with nitrox I notice a slight buzz, which is similar to 2 martinis on an empty stomach at a bar. This used to be called Martini's Rule, a long time ago. Now it is simply called nitrogen narcosis.

 

[Ice9]

at 120 on air, I can't spell or write on my slate with any speed at all. Its real slow and I have to concentrate like crazy. Its kinda a funny feeling for me...

 

[Gombessa]

An Instructor friend of mine in Key Largo likes to tell of a diver he was supervising on a wreck dive who proceeded to hand off his primary air source to an Eel which was lying on the timber beneath him. The student told my friend later that he was under the impression that the Eel was in an OOA situation and was only trying to provide assistance.....

Hey, don't leave us hanging with a story like that. Did the eel make it?

 

[in_cavediver]

For me, the effect of narcosis has a lot to do with the overall 'feel' I have. It tends to amplify that feel, be it anxiety, peace or concern. Other factors can serve to intensify this such as exertion, cold etc. It also varies with physical shape as well, such as did you get a good nights sleep.

Basically, you dive to any depth, you get some level of narcosis. It varies day to day. I have been at 120' trying to remember which way to a wall in a quarry, been at 150' rigorously watching my procedures in a cave and at 180' greatly enjoying the dive (ok, the 180' it was on mix).

For me, to dive deep, I like Helium.

 

[jpsexton]

Diminished mental capacity is a great description. During a 75' dive in cold water, wearing a wetsuit, with low vis, and a task to complete for AOW, I was so Narced I simply could not comprehend things going on around me. Since then though I've been much deeper and barely felt anything at all but it was in much better conditions. Depth is what causes Narcosis but conditions including task loading can increase the degree you feel. I think that's why some people say they have never felt it, they simply have not been in the right conditions.

 

[sidneydiver]

I had a weird experience yesterday in my tec class. We were diving in 40 Fathom Grotto. We got down to 155 feet and did some narcosis skills with our instructor which I didn't have any problems with. We then descended to 165 feet and the visibility was terrible, it was pitch black and very silty. I had the strangest sensation that my feet didn't belong to me, they felt like they were made of jelly! It was very odd but not altogether unpleasant! It went away as soon as we went back up to 155 feet.

 

[DiverBeth]

I was at 100ft on a wreck and it took the DM a couple of extra bangs on her tank to get my attention that it was time to start up. I remember feeling euphoric with no cares about anything.