Getting Narc'd

In DiveCutie's thread she says she got narced on her first deep dive. Last week in NC Wreck Maniac (Dale) and I were discussing this subject. I have never been narced.

Jill...you and I had that discussion the other day...you may have over 300 dives but how many are deeper than 100'?

Dale - Since you asked and I was curious I just tallied them. 44 dives under 100 and another 67 between 80 and 100. And no I have never been under recreational limits, that is not why I dive. Most under 100 were for wrecks, the others for sharks. Actually I was surprised to find I had been below 100 as many times as I have.

Can any one tell me why some folks get narced and others don't?

i don't think anyone knows. the same happens with feeling drunk (not being "legally drunk"...the sensation that you are hammered). why do some people get loaded quickly, while others don't feel it until they've emptied the bar?

nitrogen at sea level is an inert gas. just takes up space. but, put it under pressure, and that previously innocuous gas dissolves more readily into the bloodstream and is deposited within the body's various tissue compartments (eg, fat, muscle). the brain and nervous system is one of those compartments.

while nitrogen dissolved in, say, muscle fibers doesn't really do much, it's a whole new ballgame in the brain. it acts as an anesthetic, probably changing membrane potentials and a lot of really boringother stuff.

i think the variability of response to that anesthetic effect depends on how sensitive an individual's brain cells are to the changes to their membranes.

in other words, who the hell knows???

as an aside: it has been shown (yes, someone actually got FUNDING to study this) that REDHEADS react differently to anesthetics...usually requiring more than someone else.

so its insane in the membrane huh?

i'm sure there is a psychological factor as well.

if you want to be narced, you will be narced.

the vast majority of my dives have been to deeper than 100 feet, and i've never been able to say, "wow, i'm narced"
and i didn't suffer from memory loss, i remember all the dives, and what i did during the dives.
a few times i had some paranoia and anxiety, but considering the situation during those few dives, i'm not sure if it was caused by nitrogen. in all cases i simply stopped, took a few breathes, collected my thoughts, and proceeded slowly.


and i'm still here.

'course, i can't dive right now. grrrrrrr
but maybe soon

I used to think that I didn't get narc'd. I thought I felt normal at 100+ feet. I realized this was not the case when I hit 155 feet on air. It was it deep, cold (46 degrees), and dark. I was in the middle of an underwater forest. It really was a forest, as it was a man made lake and their were still trees down there, kinda spooky. But the thing that I realized was the more I got narc'd, the more I became comfortable underwater. I noticed as I was heading down the line to the enter the forest I had a feeling of apprehension. But as I approached the forest at 100 feet, it all seemed to magically go away. As I moved deeper into the forest through all the branches I felt no uneasiness at all. I knew that I had to make sure that I didn't get tangled in the line or in a branch, but I wasn't nervous. As I hit 155 feet I felt so comfortable that it almost bordered on complacency but I still kept track of my runtimes and was on schedule. It was an amazing feeling. Their were sparkling colors all over the place that it felt like it was a light show. Now my dive buddies were Narc'd out of their gord too. But instead of feeling the peaceful bliss I felt, they were in a constant state of paranoia. Worrying about their runtimes, psi, etc. So now I know what it feels like when I get narc'd. Do I get narc'd at 100 feet? Yup.

The physiological effect of most drugs is to interfere with the normal function of the nerve endings in the brain (partitions between cells). Drugs such as alcohol, cannabis and others inhibit the flow of neuro transmitters (chemical messengers)between brain cells and prevent them from working effectively. This is why people under the influence of drugs have diminished mental capacity, there brain literally cannot make the connections. Nitrogen under pressure is lipid (fat) soluble which means it dissolves into the outer layer of the brain cells which could mean that it acts like a drug and decreases the functions of brain cells. Thats the science bit of why Nitrogen would cause narcosis, or diminished mental capacity. (Any doctors please feel free to modify the above statements)

Can any one tell me why some folks get narced and others don't?

Like any other drug, you can build up a tolerance to it, Sheck Exley dived to over 400 ft on air, whilst others will reach their tolerance at 100 ft. It is up to the individual and their physiology.

Personally I have felt narced out of my brain (literally laughing at stupid stuff) at 110 ft after a hard night out and felt fine on the same site after a good nights sleep. I have found a good nights sleep will mean u get less narced during a deep dive. Also you can build up your tolerance by doing progressively deeper dives.

Helium is a much less lipid soluble gas, ie it dissolves into fat (e.g. the cell walls of brain cells) much less readily than Nitrogen. This is why it is used for deep gas mixtures. Ever heard of Heliox (helium + oxygen) or Trimix (helium +oxygen + nitrogen). These mixtures have less narcotic potential as they contain less nitrogen.

If you want to be less narced, I would advise; have a good nights sleep, be healthy and build up a tolerance to it by doing regular deep dives.

I build up the tolerance as well. I have more than a few dives below 100 ft. and yes, I do get narced if I haven't slept well and may be a little uptight. Cold water is another factor.

I get less narc'ed that when I started deep diving, but it still happens. I get control of my breathing and normally it goes away. Another issue is CO2 build-up from shallow breathing. This will make you feel narc'ed at times.

Take care of yourself, control your breathing and don't do your first deep dive too deep, too fast.

PS, when narc'ed, I tend to get the paranoid feelings and anxiety so I try to avoid it as well. Also, I intend to take the courses necessary to use helium in my breathing mixes before I do too much below 130 ft. At depth, I don't like my judgment impaired.

I just do't feel it, but then - I don't feel drunk until it's too late, either.

When I drink, I write down the time of each beer and analyze how I must be affected, really. Showed it to many a cop. They were - interested.

When I dive, I assume that the dulling sensation will start immediately as I go down, 10 ft, 20, 30, and on, worse at 100, 150 and on. I remind myself of this and attempt to act more safely. Try, anyway.

Just once, at 150 feet I felt anxious, but that was the Blue Hole itself, I think. A few days later at 162, nothing.

The narcotic effect of diving is probably one of the enjoyments of it for me.

excellent job there, rad boy.

brad.....i did indeed forget the psycho part of feeling narced (and who better to bring it up, huh bud??!!).

Well since Sheck dove to 400 feet on air, and Falco (the chief diver of the Calypso) did over 300 ON HIS FIRST DIVE, I won't feel so bad mentioning that I have gone well past 250' more than a few times on air. Of course I would not recommend it. But at that depth, you reach a point where you certainly are not asking yourself "am I narced?"

At least for me, the entire universe goes WAAAWAAA-WAAAWAAA-WAAAWAAA and my vision narrows quite considerably. When I reach for my console I actually wonder if it is my arm reaching for it or if it is someone else's. But it's not the nitrogen that would kill you--it is the oxygen. So I am quite certain that if my respiration rate was elevated by any kind of anxiety, my risk of oxygen toxicity would greatly increase. So I will speak with experience (if being able to write this after such dives is such proof) that the key to tolerance of gases under pressure is relaxation, and therefore reduced respiration rate, and therefore reduced metobolic rate. All experienced deep air divers are noted for a ridiculously low respiration rate.

- Kent

Very interesting. Lots of misconceptions here.

No one builds a tolerance to narcosis. With repeated exposures, you will learn to deal with it. You are not less affected.

I have never been narced.

Yes, you have. You were just unaware of it at the time. I've been narced many more times than I was aware of symptoms. I'm always aware I am narced when I dive, I've noticed symptoms twice.

Can any one tell me why some folks get narced and others don't?

No one can tell you why because it doesn't happen. Studies have shown everyone is measurably affected by narcosis at depths of 30 ft or greater.

I've never "felt" narced but I was, once I was having problems moving the controls on an Ikelite housing at 170' and the obvious never occured to me till I came shallow that the pressure was holding them in.
Same thing when I was o2 starved thanks to the USAF, you don't realize what you are missing or your vision is fuzzy till you get the o2 and things clear up.

ahhh, i knew this discussion would draw yoda out of the forest....

I'll be back with more when I have more time.

Studies have shown everyone is measurably affected by narcosis at depths of 30 ft or greater.

To add my 2 psi...

Being narc'd is not an all-or-nothing thing. You can be slightly impaired and not even realize it, even at shallower depths.

I learned this first-hand during one of my cavern dives with Walter in May. I experienced a slight degree of impairment at about 50 feet, and didn't even realize it at the time.

We were at diving at Blue Grotto in Florida. There is a large open room that is around 50 feet deep, where open water divers are permitted. Below that lies the caverns, where only advanced open water divers and above, are permitted. One of our group was not AOW certified, so our plan was that I would stay with him while his mother and Walter checked out the cavern, then after that Walter and I would check out the cavern while she stayed with her son. We had all agreed upon this very simple plan. Yet when Walter headed into the cavern, I automatically started following him, as if I was on auto-pilot. My mind was focused on one thing -not losing sight of him as we entered the cavern. It was like my brain had tunnel vision. He signalled to me to stay, and it took me a moment to realize what I was doing. Then I felt really like an idiot, and I even said "DOUH!" (like Homer Simpson) into my regulator!

We disussed what happened after the dive, and Walter pointed out that it IS possible to be slightly narc'd and be partially impaired at this depth. I have done deeper dives before, without having something like that happen, so it just goes to show that it is unpredictable, it is something we should watch for, and not get complacent about it just because we are doing shallower dives.

Safe diving to all,
Laura

Very interesting. Lots of misconceptions here.

No one builds a tolerance to narcosis. With repeated exposures, you will learn to deal with it. You are not less affected.

I have never been narced.

Yes, you have. You were just unaware of it at the time. I've been narced many more times than I was aware of symptoms. I'm always aware I am narced when I dive, I've noticed symptoms twice.

Can any one tell me why some folks get narced and others don't?

No one can tell you why because it doesn't happen. Studies have shown everyone is measurably affected by narcosis at depths of 30 ft or greater.

Again, while I agree in literal terms, the practical is somewhat different...

I guess that the correct way to say it is that some days you get more narc'ed than others. It is like some days with very little sleep and little in my stomach two beers may knock me on my can. Other days, I may be able to put down a six-pack with no effect noticeable to me. In either case, it wouldn't be good idea for me to operate heavy machinery, LOL. As we all get used to fuzzy feelings of inert gas narcosis, we get used to operating that way. Here, I agree with Walter. It is just that on some dives, I notice it far more quickly than others.

As the one poster points out, breathing has a great deal to do with dealing with inert gas narcosis. One way that is guaranteed to make the problem worse is to be breathing heavy at depth. This is another reason that panic at depth can be a problem. The breathing rate picks up and the narcosis will intensify. For that reason, most trained deep divers pay close attention to their breathing.

In many cases, Helium mixes are becoming a more popular solution to the issue. At least one training agency recommends Helium on any dive below 100 ft. in depth. Other agencies offer courses in Helium at recreational depths, but don't seem to push the concept as heavily. I don't necessarily endorse this myself, but it is a tempting thought to the photographers among us to be at 120 ft. with next to no actual narcosis. This makes it so much easier to concentrate on getting good photos. The video people talk about how their video improves by a huge amount when using this technique.