Nitrogen Narcosis - Deep air dives

[Landlocked123]

All the information I have been able to find so far states there is no fully understood mechanism of how it takes place. Does anyone have personal experiences with Narcosis they are willing to share. Would be helpful to know depth, bottom time, symptoms, workload at the time..etc

 

[northernone]

So I totally get the concept of not being able to fully self diagnose oneself but same as a drunk person or person with a buzz you know when you either one of the two. At least I did before I stopped drinking 4 years ago. As i mentioned we performed the tasks we had set out to achieve and we are intentionally breaking up tasks over multiple dives so as to not task overload. I think had we been experiencing moderate to high level symptoms we would have not been able to perform the tasks. I am going to read up on as many studies I can find. Certainly the risk if real as we were exposed to a PN4.2. Sunday we are executing another dive to 145 this time to attach a lift bag to the weight holding the shotline in pace as we need to move it to a shallower depth. Bottom time is going to be 2 mins max.

Heres my personal experience, a data sample if you will.

Calmly doing familiar tasks at a relaxed pace is easy when narced and symptoms go unnoticed.

I can calmly tie any knot I know at 280ft on air (last experienced 5 months ago) without noting added difficulty... But trying to untangle a birds nest of string at 120ft is challenging when feeling pressured to hurry. I can clearly notice my performance degradation. A few hard fin kicks and the co2 buildup narocisis feelings set in fairly strongly too. All depends on the dive and the day.

Narocisis bites hardest when we're oblivious to it's effects.

As mentioned up thread, trying a few puffs of trimix is an eye opener at depth. Particularly with narced divers nearby. Try being the only sober one at a party and suddenly every one's dancing isn't so skillful.

 

[RyanT]

Being the only sober one at a party and suddenly every one's dancing isn't so skillful.

Reminds me of a dive I did in July on air to 148 fsw. I was pretty narced and knew it. Aside from a little buzz, I also noticed it took me a couple of tries to get neutral (not normal for me). Another guy on the boat was diving mix and later commented that it was clear that all of us on air were narced.

 

[Landlocked123]

Northernone I get what you are saying. You have my attention. Sounds like there is an unknown out there with respect to where that threshold is and we are probably flerting with it right now. We may consider a plan B and just place a hook ok the 50lb weight and say f... it and have someone haul it up from a boat or something.

 

[Landlocked123]

Ryan thanks for sahring.. all great feedback.. all going to be taken into consideration for Sunday.

 

[MaxBottomtime]

CO2 narcosis is the worst but easiest to overcome. If you work too hard at depth and suddenly feel a rush of narcosis, stop what you're doing and take two or three deep, slow breaths. It should clear up enough to allow you to continue. Nitrogen narcosis only goes away if you ascend. I've gotten narced simply by descending an anchor line while deep on air.
I made a dive to 240 feet on air and while I could feel the buzz it wasn't so bad that I couldn't read the name on an instructor's slate I found in the sand and recognize it. There were also two lights, one that worked and one that didn't. I clipped my finds off and began my ascent with no problems. On another dive to 100 feet I got pretty narced when one of my buddies asked me where his buddy was. I looked around and was suddenly narced. I ascended twenty feet and was fine, but it bothered me as it was the first time I felt narced shallower than 150 feet.

 

[Superlyte27]

These threads always aggravate me. When people say they've been to X depth with no symptoms, I just want to smack them. I used to be one of you guys. Having done 200-270' dives on air regularly, I thought I had everything under control. There was a book I read back in the day that said, "surely I would know it if I were crazy". Nope! And you might not know it if you're narc'd.

One day I woke up and took a class for Trimix. Without telling anyone, weeks before I went to Eagle's Nest with air on my back and Trimix in a pony bottle. Ultimately, it was like tithing in church. I did it to prove everyone wrong. Instead, I had to come to the realization that the masses were right, and I was an idiot. Almost instantly I felt a change. A fog I didn't even know was there cleared within seconds. I felt brilliant, alert, aware.

 

[jadairiii]

From 1992, when i started tech diving to 1998 all I did was air, down to 200 +/- regularly. Other than a few "yikes" moments that I believed was part of the risks associated with deep air, I was "good" on air.

Then came my first mix dive on a wreck i had done regularly in about 180' (max). Shocking how much I could see, remember and accomplish in just one dive. But the most fun is when you (and buddy) are the only mix divers on a tec dive trip to a deep wreck. Watching the other air divers is like being the only sober person at a St Patrick's Day party. Even more fun is talking to them afterwards of what they remember.

 

[MaxBottomtime]

I've dived deep air and trimix. While there is a clear difference I have never forgotten part of a deep air dive. I wonder when I hear statements like that if the diver simply didn't see something and was later asked about it. I heard one diver tell me he forgot thirty minutes of a dive. I would run, not walk to my nearest neurologist if that ever happened.

 

[jadairiii]

I...While there is a clear difference I have never forgotten part of a deep air dive. ....

How would you know? And maybe "forgotten" is the wrong term. "Failure to perceive" certain events during a dive would be a better term.