Narcosis Experiences

[oldschool]

I don't know if this should be posted somewhere else or not. Anyway, it might be interesting to hear from those of us who have entered the world of narcosis and what we experienced. I'll start out. This summer, my buddy and I were diving in Lake Travis, Austin, TX. We decided to check out the "Pecan Grove", a grove of large pecan trees at about 110 ft. We planned the dive out. It was also decided that if we got silted out and lost visibility of each other we would search two minutes and then surface. Vis was excellent (20' plus). We got down to the grove and sure enough, got silted up. As planned, I began my ascent after two minutes of searching the immediate area keeping a very close watch on my depth guage. Air was plenty. I immediately noticed I was not ascending according to my guage. Being in a "grove", I checked to see if I had gotten snagged on a branch or something. I was clear, but still not ascending. I began popping air into my bc slowly. Still no movement. Suddenly, I realized the problem. I had been fixated on my maximum depth needle. I was looking at the wrong needle. I then saw I was at 65' and rising quick. I immediately dumped the air and decended back to 90'. I then began a slow ascent with a five minute safety stop at 15'. I got to the surface and met up with my buddy. This is a long thread but I guess my point is that being narced does not mean you become a complete and total idiot. I thought I was thinking very rationally, following the plan, and even looking for a logical explanation for not beign able to ascend. And in that lies the danger.

 

[1_T_Submariner]

If you where thinking rationally you would not have added air to your BC to go up and you would have noticed that you where ascending. Good recovery once you came to your senses. I'm not trying to be harsh I think I am actually agreeing with you.

You didn't mention experience level. Is this your first dive to those depths? Was it colder than last time you did that type of dive? New equipment?

Edit:
It does sound like a pretty cool dive site. Are the trees pretty intact?

 

[oldschool]

Currently OW. Planning on AOW and Nitrox in the near future. No, my deepest dive to date is 130'. However that was in Cozumel. BIG difference. Water temp that day was 84 degrees with no thermoclines. This summer, Lake Travis was unbelievable. Because of the tremendous amount of rain we had in central Texas, they had opened the dam earlier, causing the cold water at the bottom to flow out. I've logged plenty of dives though in cold and dark. It was my second dive with a computer (VEO 250). However, I was still primarily relying on my guages, slowly getting used to and transitioning over to the computer. I still dive with my guages, but the computer is now my primary source of info. A few weeks later, I made another dive in Travis to 120'. No noticable affects.

 

[oldschool]

Oh, reference the trees. Yes, from what I saw, they are intact. Pretty errie. If you haven't dove Lake Travis, you should. Look me up if you're in this neck of the woods. Excellent topography including massive ledges, vertical walls, and lots of toys ie. cars, boats, planes, platforms, and such. Vis a temp were exceptional this summer and not the norm.

 

[Nemrod]

You could have been narced a little, it is common for the thinking cap to slow down a bit but you know, in diving it is common to blame every touch of confusion, disorentation or dufus move on narcosis. Do pilots who are flying on instruments and then loose control have narcosis--NO! They nonetheless often fixate on a particular instrument even though their training tells them not too. Maybe you were just confused and need to get more familiar with your equipment. You fixated which is more a symptom of overload than narcosis persay. N

 

[oldschool]

Excellent point. If in fact it was "overload", I've taken steps to avoid it in the future. The minute that little voice tells me to abort the dive or ascend and make the dive at a shallower depth, I'm all ears. A concience is a terrible thing to waste.

 

[oldschool]

Ok, I bared my soul on my experience. Anyone else?

 

[Drewski]

Just to keep these "narcosis" threads educational for those who are interested in the topic, I always suggest reading the information presented in this link and this DAN article...

Food for thought...

 

[Nemrod]

I remember sitting in class and reading about "Rapture of the Deep," the dreaded narcosis, frankly, I am not sure I have ever experienced it (acute) and I have been over 200 feet numerous times on air. Yeah, there is a mental slow down but just as in the links provided above training, conditioning and awareness are key. Those who become anxious or who fear something often find themselves prey to their fears. Mild narcosis may contribute to anxiety or fixation or confusion but I think more often it is the other way around, the mental overload from anxiety absorbs your spare (mental) capacity. Experience, training, conditioning increase that "spare" capacity minimizing the effects of nitrogen narcosis and therefore somewhat innoculate you agaisnt it. That is my operating hypothesis and I have seen nothing to dissaude me from it. I wish I could give you a story, I love telling stories but alas, I have never been acutely narced. Most healthy people, rested and prepared should have little fear of incapacitating narcosis at least within sport diving depths to 130 feet.

N

 

[DOkie]

Acutally pilots who are in an unpressurized aircraft CAN suffer from Nitrogen Narcosis. Maybe you should do your research next time. I have a very difficult time believing that a diver can go to a depth of 200' (on air) and not experience Narcosis. Although I certainly agree that experience can help you recognize narcosis, and therefore assist you in overcoming it, how are training and conditioning a factor for "innoculation". Overloading is a huge factor in being narc'd. It has to do with your breath rate (it's simple physics).

I'd like to invite anyone who thinks that they have never been narc'd dive to at a depth of 200' in pitch black water, that's not only dark, but silted so that you can't see lights, and has a temp of 33 degrees. I believe the effects would be more obvious in those conditions.

Personally, my cut-off is 170. That is for safety reasons. At that depth and on very familiar dive sites, I'm smart enough to realize the effects of narcosis on me. Anything deeper and my reasoning and reaction time is not what it should be.

Quite honestly, I can always tell when I'm narc'd. I get this undying urge to sneak of up lawyer fish....