How Does Narcosis Effect You?

[NYCNaiad]

Nark for me is molasses for brains. Sometimes increased apprehensiveness. I've yet to experience the fun and/or comical stuff I heard numerous stories about during my OW class. I really don't like being narked.

Finally someone else who feels a bit like I do! I get paranoid narc'd. I suppose it's safer to have this type of narcosis, but it is not fun at all...& unfortunately, I feel the effects around 90/95 feet at least on my 1st dive. After a series of dives, I can then go deeper w/o feeling the effects. I also get severe tunnel vision where I can only see a circle a foot in diameter & everything else is black. Once I go up a little, it's fine...but I've learned to keep my 1st few dives less then 90 ft. My deepest dive ever was 137ft.

 

[JMBL]

My personal experience with narcosis (I dive deep on air regularly up to 60 m) :

- my very 1st time : 38m on my PADI Advanced, in the Med, during summer 1991. I felt good ! Sooooo good ! The site was lovely, water was clear and warm. Didn't behave erratically and very quickly, it rang a bell to me : don't you remember Cousteau's films you jackass ! You're narked ! So watch out. While debriefing with my instructor, he told me my behaviour had been ok, but he has his doubts cause I was obviously enjoying myself a bit too vividly.

- usually below 35m to 45m everything is ok, but I've noticed my brain is bit slowed down. Slowed down, but not impaired. Already had to assist out of breath buddies at those depths and we've managed it allright to the surface,

- below 45 m and up to 60 m : there it's more like slow motion movie, I usually try to keep on edge, cause I know I'm narked even if I don't feel it. When water is clear and warm, it's ok.

But when it's cold and dark, things aren't so easy. Remember a dive in the Biscaye Gulf in July : while changing on the dock (above 30°C), the sun roasted us, then 45' of uncomfortable navigation cause of the rough waves, then 18' at 50 m in a 12°C water, dark as pitch. Usually, it's a dive I enjoy very much. My buddy was a friend, and a very able diver, everything should have been terrific, but I've absolutely no memories of that dive ! I know I did everything as planned (we dove run time : air + 50% EAN) and my buddy told me I was answering his hand signs correctly and that we communicated easily all the time, but don't ask me what I saw, I haven't the slightest idea...

Another unpleasant experienced with narcosis : July, blue water and perfect conditions in the med. Dive planned on a rock which rises from the bottom around 50 m up to 10 m more or less. My instant buddy was a 4* CMAS diver (or DM if you prefer to call him so), myself I'm a 3* CMAS diver. We dove straight to 50 m, not particularly fast, easy going I'd say. Then, all of sudden, my 1st went amok, I heard a blow out, then bubbles coming out very fast from it. Couldn't reach my valve, asked my buddy for help, I didn't feel easy but didn't panick and gave him the right hand signals correctly : he just kept looking at me with a blank stare... So, I called off the dive and signaled him 'going topside'. Thanks god he followed ! But while waiting for the boat to come (in less than a minute) I got a very harsh bunch of rebukes for spoiling his dive for no good reason. He denied I ever had a problem with my reg... Cannot say we were on the best of terms after that...

Hope it'll help.

 

[Diver0001]

I dive regularly to 50m/165ft on air and I can safely say that there is no rhyme nor reason to how narcosis affects me on any given day. Sometimes I can get to depth without feeling overly impaired and sometimes I'm starting to feel pretty bonked by the time I get to about 35-40m. Mostly I just feel vague and sometimes I start to giggle a bit or have some loss of focus. I think on most days there wouldn't be much chance of me accomplishing complicated tasks at 50m in anything like the same amount of time it would take at a shallower depth.

What I have noticed on the few times that I've made video at that depth is that my perception of time is VERY VERY different during the dive than it appears on the video when viewed after the fact. When I'm deep time seems to progress fairly slowly but on the video it invariably shows things happening a LOT faster than I thought they were during the dive.

R..

 

[kensuf]

My personal experience with narcosis is that it's like boiling a frog. Everyone gets narc'ed but you don't necessarily notice it on descent because you're anesthetizing yourself on the way down.

FWIW, CO2 buildup makes narcosis worse. Crappy regs, exerting yourself, or shallow/skip breathing are a quick trip to narcosisville.

Back in my young and dumber days (I'm still dumb, just hopefully not as dumb), we used to do a fair amount of deep air diving. The Lockwood tunnel in Eagle's Nest is in the 220-230' range and I did a dozen, or so, dives on air there before 1998. All seemed great on those dives until I had a dive where my primary light failed and I had to deploy a backup light, that ended that. It turned out my manual dexterity was gone at 230' on air, who would have guessed that?

We also used to be afraid of helium on deep trimix dives, and in the mid-90s would switch to air at 190' to get off the helium as quick as possible. Even though I'd been to 190' (and deeper) on air many times, the experience of coming off helium to air at 190' was like popping a whippet and getting kicked in the face by a mule, all at once. Wheee!

It doesn't have to be that deep either, narcosis hits well within the "recreational" advanced diver range. The past month I've spent every weekend doing some deep diving on trimix. Last weekend I was doing a couple of 290' dives at Eagles Nest with a friend from Venice, FL. Personally, I don't believe there's a big risk of IBCD on shorter, shallower (~330' or less) dives, so I'm not always concerned with having helium in my 120' travel gas. The reg I used on my 120' bottle last weekend was not as well tuned as it could have been, and I gave myself a slight CO2 hit coming off 14/55 at 120' -- the ensuing narcosis caused me to fumble for a minute or two while doing my bottle switches.

 

[boulderjohn]

For those of you who think you're not narced at those depths, I challenge you to a little experiment. Go do a deep dive (below 100 feet) with someone who's on a helium mix. At the deepest part of your dive (arrange this in advance, so they know what you're doing), signal that you want to breathe off their gas. Do so for a couple minutes, then go back on your own gas.

My trimix instructor did that with me. He was diving air. and I was diving mix. We switched for 2 minutes. Later on he talked about how much better he felt, but I didn't notice a thing.

I have never felt anything different on deeper dives on air. (My deepest on air was about 180--I don't do that any more.) What I do notice when the occasion calls for it is that I am stupid. I could relate a number of anecdotes in which it was obvious to me that I was narced because of the obvious stupidity. Interestingly enough, the most obviously stupid of all was on a mere 100 foot dive. A friend of mine, a tech instructor, said his worst narc experience was at only 85 feet.

I did most of my cave training at depths close to 100 feet, and I felt than and feel now that a lot of the problems I had on those dives was related to narcosis. I felt OK, but I could tell I as I was doing things that I was being uncharacteristically inept. I have heard other cave divers say the same thing about their training.

 

[rongoodman]

Lynne often mentioned some potentially serious mistakes she made in her Cave 2 class which she attributed to narcosis.

 

[rhwestfall]

Cold water, 125' - I spent about a minute fumbling to get a lift bag out of the pocket on the bottom of my plate. Couldn't figure why I couldn't get at it. Didn't have the problem in class and in drills prior. Was getting quite "upset".

The opening was on the other side.....

I've shot video footage, and later when watching it, don't remember having filmed some of it....

I never know when it will hit, or how badly it will be. I've had it at 110, and at times when deeper, not nearly as severe.... notice I didn't say "didn't have it".....

 

[100days-a-year]

Video is great to quantify the obvious physical behavioral changes but it doesn't always show the narrowed perception or poor decision making.My performance is very good deep by I am acutely aware of being in a different state of mind and try to offset that by simplifying my dive wherever possible.

 

[yle]

My handful of dives between 120 and 135' have been AWESOME!! That's how I remembered them afterward. But I didn't see anything on those dives that I hadn't seen on shallower, although not-nearly-as-awesome, dives.

That's how narcosis affects me. Fortunately, shallower than 120' my dives are nice, but don't seem so awesome.

 

[PhatD1ver]

Doc of course has it nailed. I've been to 30m multiple times, and had little to any noticeable effects. Doesn't mean it isn't happening. I was in Coron last summer, feeling fine, we were at 36m, entering a wreck when "Manila Mama" goes barrelling by and bashes me with her fiin, completely knocking my mask off and reg out of my mouth. I recovered, but I was livid, and that was all it took to cause me to really feel 'grogged' (my word for the feeling of uneasiness and disorientation that you get like being drunk)...

I followed training, ascended about 5 meters, got myself composed, and then followed them into the wreck (still cursing her under my breath).

My deepest (in training) was 46m, and I was working a little into a light current. I could feel it just hanging there at the edge of my consciousness, similar to the feeling you have when you've had a couple beers and think your 'buzz' is coming on. Only with being narc'd, any number of factors will flip that switch.