Nitrogen Narcosis, what's up with that?

[muteki]

Getting narced is usually pleasant for me - bit of a buzz, and it actually makes me check my air and NDL even more out of caution. Best experience was getting narced on wrecks, it makes the eeriness even more enjoyable! I normally feel it right at 30m, not even at 29.

 

[dumpsterDiver]

I originally posted this video for myself and friends, but I provide a link because I think it does show significant narcosis. I was solo on air; the depth on top of the wreck is around 160 ft.

One of the keys to being a decent spearfisherman is knowing when to take the shot. You need to be able to line up the shot quickly and efficiently, make sure that you have the correct shot angle, that the distance is not too far and neither rush the shot nor avoid taking it when the moment is right. Not all that different from underwater photography, but spearing is easier because you don't have to worry about lighting angles too.

This fish is moving slowly, is within range, is giving me a perfect broadside shot, yet I kept hesitating, over and over. It may look like these were minor delays, but they are excruciatingly long for me to watch. Then as the fish gets further away and begins to move away faster and no longer gives me a good shot angle... I FINALLY take the shot.

I have no idea why I waited so long. Luckily I make it, but I can only conclude that my hesitation on this shot must be caused by narcosis. I don't normally suck this bad. I have many head cam videos and upon review of them, I normally see no detectable signs of impairment (even though I know that I am impaired). I wonder if other people have videos that appear to show narcosis?


[video=youtube_share;3O058N3AvYc]http://youtu.be/3O058N3AvYc[/video]

 

[scubadada]

I was born the same year as TS&M and grew up in SoCal. As several contemporaries have pointed out, I also had a significant experience with altered states. I'm sure I am affected by narcosis at depth and am occasionally overtly aware of it. However, I've not had any dysphoric episodes. I have often wondered if my previous experience has contributed to this

 

[Drin]

I was born the same year as TS&M and grew up in SoCal. As several contemporaries have pointed out, I also had a significant experience with altered states. I'm sure I am affected by narcosis at depth and am occasionally overtly aware of it. However, I've not had any dysphoric episodes. I have often wondered if my previous experience has contributed to this

I've been narced more than a few times in various waters both warm and cold. My general experience has been that warm water narcosis is a pleasant experience replete with periods of comfortable mental drifting. Cold water narcosis on the other hand is usually a paranoid experience with feelings of unease, usually accompanied by a mental loop repeating "we're lost" or "we shouldn't be here".

I've always attributed the difference to cold and dark vs. warm with high viz.

-Adrian

 

[scubadada]

I've been narced more than a few times in various waters both warm and cold. My general experience has been that warm water narcosis is a pleasant experience replete with periods of comfortable mental drifting. Cold water narcosis on the other hand is usually a paranoid experience with feelings of unease, usually accompanied by a mental loop repeating "we're lost" or "we shouldn't be here".

I've always attributed the difference to cold and dark vs. warm with high viz.

-Adrian

That's an interesting point. I have many more warmer water, not always great vis, dives than cold water. I only have about 40 deeper cold water dives and have not noticed the differential in narcosis experience.

 

[MXGratefulDiver]

I was born the same year as TS&M and grew up in SoCal. As several contemporaries have pointed out, I also had a significant experience with altered states. I'm sure I am affected by narcosis at depth and am occasionally overtly aware of it. However, I've not had any dysphoric episodes. I have often wondered if my previous experience has contributed to this

I was born a few years before TSandM (1952) and spent most of my '20's and '30's as a faithful follower of the Grateful Dead (hence my screen name) with all that implies. That said, those experiences in no way prepared me for diving narc'd ... the "buzz" is completely different. I wouldn't want to scuba dive while high on hallucinogens and I don't particularly enjoy diving while narc'd ... for me it's an anxiety-inducing experience and, while I can generally handle myself OK, it's not something I would do intentionally.

... Bob (Grateful Diver)

 

[Nemrod]

I had (or possibly still have--no need to go there) a friend who would spritz the intake to his compressor with whisky. I got a heck of a headache several times after he filled my tanks. I guess it has been pointed out to me that the whisky might have ignited producing carbon monoxide, not sure about that as I have not analyzed it in my head, I just figured whisky at 130 feet in Hospital Hole was not a good combination. N

 

[Akimbo]

The US Navy ran all of us to 285' in a chamber in First Class Diving School, once dry and once in a wet pot in Mark V deep sea gear. We were also learning to operate the chamber so we had the opportunity to see how narcosis affected us and others. Narcosis didn’t sneak up on anyone given the depth and training; we all knew we were going to be compromised.

I think it is fair to say that mental preparation and being self-aware makes a huge difference in performance. We knew that we were not functioning normally and could compensate to some degree on familiar tasks like tying knots and putting together pipe puzzles. Vision, dexterity, and speech were all affected in different ways. Problem solving was harder to measure during such short exposures but even the cockiest of us reassessed our invincibility.

I have not seen studies that confirm or deny the phenomenon but nearly all commercial divers and supervisors I have spoken with believe repeated short-term deep air exposure increases narcosis tolerance and improves performance. Most people I have spoken with think that nitrogen narcosis is quite different than being impaired by alcohol. Mental and physical control under narcosis is much better.

I can see how narcosis can be much worse if you have never experienced it and it sneaks up on you. It is a shame that chambers are so expensive to operate because it is such a safe way to learn about it.

 

[boulderjohn]

For me narcosis presents no noticeable feeling whatsoever. It just presents itself as stupidity. When I have been aware of it, I have had an occasion to do something that demonstrated that stupidity. In each case, if the situation that demonstrated my stupidity had not occurred, I could have easily completed the dive and sworn I had never had any effect. I have never had a situation arise where I had to do something serious, like a life-or-death response, while under the effects of narcosis. I hope I never do.

A couple of years ago, a dive shop owner in Cozumel and two friends decided to do a quick, one tank bounce dive to 300 feet. Narcosis is usually given as the explanation for why she continuing descending at 300 feet and was not caught and turned around until she had reached 400 feet. She died from the resulting DCS, and the friend who caught her and turned her around will never walk again.

That buzz can have negative consequences, so, like Lynne, if I want to experience what is often call the "martini effect" of narcosis, I prefer to do it with a martini.

 

[dmoore19]

My first dive to 100' was in Roatan at Mary's Place. I had an instructor as my dive buddy, though he was not employed as such at the time. When I reached 100' a feeling of apprehension came over me. I did not like what was going on and signaled him that I need to go up to 90' and level off. We did so immediately and the feeling simply went away and we continued the dive, one of the dives I remember most for 2 reasons, 1) the narcosis and 2) how 10' made the rest of the dive one of my most memorable.

I was born somewhere around the same time as Bob and TSM and I can honestly say I would never do that on purpose.