Nitrogen Narcosis - from breathing air?

[circusoflife]

"Due to its perception-altering effects, the onset of narcosis may be hard to recognize.[5][6] At its most benign, narcosis results in relief of anxiety - a feeling of tranquility and mastery of the environment."

"The most dangerous aspects of narcosis are the loss of decision-making ability and focus, and impaired judgement, multi-tasking and coordination. Other effects include vertigo, and visual or auditory disturbances. The syndrome may cause exhilaration, giddiness, extreme anxiety, depression, or paranoia, depending on the individual diver and the diver's medical or personal history. When more serious, the diver may feel overconfident, disregarding normal safe diving practices" - Wikipedia (Yea, not the greatest source, but good enough)


hmm..sounds like it doesn't just apply to being underwater.

So...as scuba divers we are taught to be aware of Nitrogen Narcosis at depth. Now...using this logic could we infer that we are all suffering from a form of narcosis on land - due to breathing air? As air is mostly nitrogen. We just don't notice our impairment - because everyone is impaired?

Now this might not make any sense until one realizes the amount of air we breathe/need is related to the quantity & type of food we eat and psychological / physical state. Also our location which influences the stress on our body -- a polluted city vs a forest.

Thus, at different points in time our need to breathe "oxygen" goes up & down. Thus -- so does our mental clarity / impairment. Such as after a big meal, when we are tormented by a particular stressing issue, eating a meal of meat/heavy carbs vs fruit, and so forth. Also the feeling/high/awareness we might get during a period of intense exercise...

There's more to this story...but would be interested to hear feedback before I let that part out.

[Darnold9999]

Belongs in the Humour Forum

[circusoflife]

so quick to reply -- without much thought...

[DevonDiver]

Yes... breathing air on land can cause narcosis - but this is determined by the relative partial pressure of the inert gas being breathed. Our bodies have adapted to breathing air within a relatively shallow band of pressure - because of that evolution, we operate normally within that pressure band. There simply aren't many places on Earth (excepting underwater) where a human being would encounter sufficient pressure to cause the high partial pressure of inert gas to cause noticeable or debilitating narcosis symptoms.

[TSandM]

I think this is quite a reasonable question. Undoubtedly, whatever chemical effect nitrogen has on the central nervous system, it has some even at the 79% concentration to which we are accustomed. And we have certainly evolved adapted to that. It would actually be an interesting experiment to do neuropsych test of people breathing air, and people breathing 21/79 heliox, to see if there are differences in performance. For all I know, someone has already done it.

However, your statements about the amount we need to breathe being related to food, location, and stress are incorrect. What sets the volume of air that you need to pass through your lungs in one minute is the rate of carbon dioxide production in the body. This may slightly increase while digesting, but is independent of location or stress. And nitrogen absorption is virtually independent of minute ventilation, anyway.

[Darnold9999]

so quick to reply -- without much thought...

Oh I thought about it.

The amount of Nitrogen absorbed in a liquid (blood) has nothing to do with how fast you are breathing, stress, what you eat, or any other factor you described. Thought that was covered in basic OW. It is certainly covered in basic chemistry. Humourous that a diver would believe otherwise.

Would the removal of Nitrogen from air - replacing it with some other gas - have an impact on perception and mental acuity? Possibly, but I doubt that it is anywhere near the level where you might say that we are all suffering a form of narcosis on land.

A fairly simple test would be to consider your mental performance breathing enriched air at ambient pressure. Less Nitrogen - reversing the "impairment". Can't say I have seen it, or heard any significant changes in mental state from anyone breathing pure O2 at ambient. Possibly more alert, but I suspect that is as a result of the additional O2 not the removal of N. I suspect if their was significant changes in mental state - reversing the narcosis you postulate we would have heard about it by now.

[Tigerman]

Oh I thought about it.

The amount of Nitrogen absorbed in a liquid (blood) has nothing to do with how fast you are breathing, stress, what you eat, or any other factor you described. Thought that was covered in basic OW. It is certainly covered in basic chemistry. Humourous that a diver would believe otherwise.
....

Do you walk around remembering every word of every thing youve ever heard or read?
Your attitude come through as incredibly condescending and full of yourself...

[boulderjohn]

.
The amount of Nitrogen absorbed in a liquid (blood) has nothing to do with how fast you are breathing, stress, what you eat, or any other factor you described. Thought that was covered in basic OW.

No, it isn't covered in basic OW.

In a thread a few years ago a very famous diver made some very disparaging remarks about people who did not believe that rate of breathing affects nitrogen absorption, and he said these people should go back to their basic OW class for instruction on this. So the two of you have exact opposite views on this, and you both believe that your viewpoint is covered in basic OW instruction.

In another thread recently a scuba instructor said that rate of breathing and stress impact nitrogen absorption, and he offered as proof the fact that a Uwatec computer has a heart rate monitor so that it can adjust the decompression schedule based on differences in heart rate. So both he (an instructor) and (apparently) Uwatec think that stress does have an impact on nitrogen absorption.

Now, I happen to agree with you that it doesn't, but this fact is certainly not obvious, and a lot of highly experienced and highly trained divers are of a different opinion.

[TSandM]

Testing people breathing 100% O2 would not be a good comparison, as there is significant reason to believe that oxygen may also have narcotic properties. That's why I suggested 21/79 heliox.

[DevonDiver]

Would the removal of Nitrogen from air - replacing it with some other gas - have an impact on perception and mental acuity? Possibly,...

A quick search using the words "helium" and/or "trimix" in a diving context may enlighten...

Gas partial pressure dictates it's effect on the human body. In respect of air... our bodies have evolved to operate within a relatively strict range of gas pressures and consistencies. Too little, or too much oxygen has an impact. The same is true for other gasses.

We are pretty adapted towards nitrogen and oxygen within a narrow margin at common atmospheric pressures. Not so for other gasses. For instance, nitrous oxide has very definite impacts at atmospheric pressure. Other gasses, less so.

A fairly simple test would be to consider your mental performance breathing enriched air at ambient pressure. Less Nitrogen - reversing the "impairment".

It is incorrect to assume that nitrogen is the only gas that has narcotic effects at increased partial pressure. A more accurate term is 'Inert Gas Narcosis'. Nitrogen narcosis is only commonly used because it is the first constituent of air to have an effect on divers at increasing pressure. Simplistic.

There's lots of debate on the narcotic properties of oxygen. At this time, divers are advised that nitrox has the same narcotic properties as air... and thus, the replacement of nitrogen with oxygen within a mixture should not be assumed to reduce the narcotic potential of the gas.

As I understand it, any discussion of the narcotic properties of an atmospheric gas at regular atmospheric pressure is inconsequential, because our bodies are evolved to operate efficiently using those gasses at those pressures. We only experience changes when non-typical gasses are introduced... or, more commonly, when the partial pressure of a common atmospheric gas is increased.