Scared of Nitrogen Narcosis

[AdvancedAquarist]

Well essentially you should not be too worried about it. Nitrogen when under pressure can act as a intoxicating drug in some circumstances. Symptoms of this may include blurred or narrow vision, loss of function in basic motor skills, headache, dizzyness, etc.

 

[fresh_fish]

I have been narc'd at 75, and it just hit me like a panic. I didn't know where I was, and the first thing I thought was follow the bubbles. (Good thing my instructor taught me that!). I have been to 118 at the deepest, and for me, the cold was the biggest factor in the reason it happened at all. I would not be so concerned about the numbers, but about the comfort and familiarity factors like vis, temp, fatigue, etc.

 

[on_two_wheels]

The validity of that in practice has been debated back and forth for a long time. Oxygen also has narcotic properties that are just as great as Nitrogen.

Nitrox is great for reducing tissue saturation, but for real reduction in narcosis you would need to look into a heliox course or similar that replaces a gas with something less narcotic.

On a side note, can you provide a source for that statement? I'm already aware of the toxicity but couldn't find anything on just narcotic effects having been proven/substantiated. I know it's assumed for planning purposes but I couldn't find a factual case study on the subject a few months ago.

 

[boulderjohn]

The validity of that in practice has been debated back and forth for a long time. Oxygen also has narcotic properties that are just as great as Nitrogen.

On a side note, can you provide a source for that statement? I'm already aware of the toxicity but couldn't find anything on just narcotic effects having been proven/substantiated. I know it's assumed for planning purposes but I couldn't find a factual case study on the subject a few months ago.

All gases are to some extent narcotic. Based on the most prevalent theory of what makes them narcotic, which seems to work in practice by comparing the gases that have a lesser narcotic effect (like Helium) with those that have a greater narcotic effect (like nitrogen), we would expect oxygen to be more narcotic than nitrogen. The problem is that oxygen is metabolized, and no one is able to calculate the effects of that metabolism effectively. Moreover, it is hard to test oxygen the way other gases are tested for narcotic effect because of the problem of toxicity.

As cave Diver said, the topic has been debated, and debated often. Some people will argue that nitrox is more narcotic than air, some people will argue that it is less narcotic than air, but the vast majority say that the difference is not significant enough one way or the other to consider in planning. As a nitrox instructor, I tell my students exactly that.

 

[dmoore19]

If the OP is still concerned about Nitrogen Narcosis, maybe she would be well served by hiring a DM or Instructor for a couple of dives to help her ease her fears and gain confidence? With only 7 logged dives (are the certification dives included in the 7?) I can understand not wanting to go any deeper than 60'. I still like <60' dives, lots of fun!

 

[Cave Diver]

On a side note, can you provide a source for that statement? I'm already aware of the toxicity but couldn't find anything on just narcotic effects having been proven/substantiated. I know it's assumed for planning purposes but I couldn't find a factual case study on the subject a few months ago.

If you look at the chart on the right hand side of this Wiki article it shows you the narcotic potency of several gases. As John already noted, one of the problems with determining this with Oxygen is that it is metabolized, so the lack of retention makes it difficult to measure. http://en.wikipedia.org/wiki/Nitrogen_narcosis

One thing to take note of is the narcotic potential of CO2. That is part of the reason why CO2 retention is such a bad thing and likely why it contributes to the "dark nark" phenomenon.

If you're looking for studies on it, you might try checking out the Rubicon Foundation. I think I recall seeing something in their database on it.

 

[on_two_wheels]

John....that's what I've read thus far. The big difference is the narcotic effect of nitrogen in the human body is a KNOWN while the narcotic effect of O2 is an assumption. I was thinking that by now surely someone would have come up with more substantial support for that theory.

I guess my problem is when I hear "narcotic" related to diving I think bad things. O2 does have a narcotic effect because breathing pure O2 makes a person feel refreshed, rids headaches, etc. However, those are not only acceptable but desirable effects. At depth, I think toxicity would be an issue long before any negative narcotic effect was revealed.

In relation to the OP, take AOW and the nitrox course and learn even more. Sorry for the hijack.

 

[Cave Diver]

John....that's what I've read thus far. The big difference is the narcotic effect of nitrogen in the human body is a KNOWN while the narcotic effect of O2 is an assumption. I was thinking that by now surely someone would have come up with more substantial support for that theory.

And that's probably why the debate continues...

 

[on_two_wheels]

Cave Diver....thanks. I'll take a look that the Rubicon info. I've seen the chart of narcotic levels but considering how efficiently the body uses O2 the numbers could be misleading. The fact we can breathe pure O2 suggests it metabolizes so well that while the narcotic potential may be 1.7, the reality might be MUCH lower. This crap is soooo confusing. I realize for planning purposes you just treat it as a narcotic, though.

 

[on_two_wheels]

Just noticed....thanks button is gone again. ???