Narked?

[Dmitchell]

Been a long time since I did anything below 100' on air. I would have told you that before Trimix I was never narc'ed.

So I guess that paranoia of watching my buddy and gauges not to mention the tunnel vision and super loud regs was just normal .

After my first trimix dive, I was like Holy Crap!

[whatevah]

Been a long time since I did anything below 100' on air. I would have told you that before Trimix I was never narc'ed.

So I guess that paranoia of watching my buddy and gauges not to mention the tunnel vision and super loud regs was just normal .

After my first trimix dive, I was like Holy Crap!

I know the loud regulator noise you're talking about - at first I thought it was a sign of my own narcosis, but then I got to wondering if the greater density of the gas at depth isn't what makes it so loud. Would imagine that the much lower density of helium makes for less regulator noise when breathing trimix. The real answer is probably that it's a mix of narc and gas density that makes us notice the noise (or relative quiet) - glad I'm not the only one I get either the gauge paranoia or a feeling of total relaxation that I don't want to lose by shallowing up - could go either way depending on the day and the conditions.

[Dmitchell]

Yea, air vs. trimix definitely has a different sound but I think air is louder yet when I'm narc'ed.

[pensacoladiver]

Have someone who you dive with who knows what you had experienced before and who understands your fears go down with you while you dive eanx and set a goal for 70fsw, then the next dive, add 10fsw and keep progressing until you know where your limit is before you start feeling anxiety then the guessing game is over and you dont have to worry about it anymore ;-)

Not quite sure I follow your logic or recommendation here. Anxiety can and does come at many different depths given multiple factors such as visibility, temp, workload, etc...

Just because you don't feel anxiety at a certain depth on a certain day does not mean you have found your narcosis threshold and never have to worry about it anymore.

I have been at 172 FSW just feeling fine and fit as a fiddle... (in truth, I probably wasn't). The very next day, I am at 161 feet in about 1/4 knot of current and ended up narced out of my mind while trying to get my breathing back under control.

[CaptnJack]

I have been at 172 FSW just feeling fine and fit as a fiddle... (in truth, I probably wasn't). The very next day, I am at 161 feet in about 1/4 knot of current and ended up narced out of my mind while trying to get my breathing back under control.

Duuuuude, helium is cheap eps. in FL. And double cheap with your own compressor...

[Dmitchell]

There's way more to it than just depth. Even the same dive over different days can feel different. Environment plays a huge factor.

I've got a spot that we should just refer to as the Narc'hole cause it will seriously mess you up. I've watched seasoned divers become practically unable to function in there. It will make you a HE convert real quick!

[RDW]

Lordy, Lordy!

I've just stepped into Mr Peabody's "Wayback Machine". (Look it up Bullwinkle fans)
This entire subject has been found in a distant place (circa mid AD1990's)
called REC.SCUBA
OK kids...it was found in a (hold on here), usegroup! A distant galaxy in a place just outside the internet.

Where is good 'ol GI3? (Farm animal stupid? Jeez Laura, you is datin' yourself. Be careful!)

Ah! The good 'ol days!

Randy

[SeanKylgod]

My point: If you sketch out when narc'd, stay away from depth.

Have someone who you dive with who knows what you had experienced before and who understands your fears go down with you while you dive eanx and set a goal for 70fsw, then the next dive, add 10fsw and keep progressing until you know where your limit is before you start feeling anxiety then the guessing game is over and you dont have to worry about it anymore ;-)

Not quite sure I follow your logic or recommendation here. Anxiety can and does come at many different depths given multiple factors such as visibility, temp, workload, etc...

Just because you don't feel anxiety at a certain depth on a certain day does not mean you have found your narcosis threshold and never have to worry about it anymore.

I have been at 172 FSW just feeling fine and fit as a fiddle... (in truth, I probably wasn't). The very next day, I am at 161 feet in about 1/4 knot of current and ended up narced out of my mind while trying to get my breathing back under control.

[Mongo]

Kitsapdiver,

I don't think you opened a can of worms at all. In fact, I think you bring up some valid points about oxygen enriched gas. You and others who assume oxygen to be narcotic have the lion's share of knowledge and experience.

My response is based solely on my experience: I have not yet dove with helium, I remember my dives when I use enriched gas, I don't get the tunnel vision as bad, I am not even remotely as tired after the dive as I was with simple air.

It may be more of a qualitative answer than a quantitative one: oxygen use results in a particular type of narcotic effect, while nitrogen and carbon dioxide result in a different narcotic effect.

[kitsapdiver]

Kitsapdiver,

I don't think you opened a can of worms at all. In fact, I think you bring up some valid points about oxygen enriched gas. You and others who assume oxygen to be narcotic have the lion's share of knowledge and experience.

My response is based solely on my experience: I have not yet dove with helium, I remember my dives when I use enriched gas, I don't get the tunnel vision as bad, I am not even remotely as tired after the dive as I was with simple air.

It may be more of a qualitative answer than a quantitative one: oxygen use results in a particular type of narcotic effect, while nitrogen and carbon dioxide result in a different narcotic effect.

Fair enough! The qualitative answer is really what the OP is going after, and while this may draw some fire from some of the hardcore recreational trimix types I think you're answer is more than completely valid. I think it is completely possible for divers to perform dives at 100 fsw with air (or Nitrox) safely.

I may not have emphasized this point enough in my first post on the topic, but I think the number of stressors that are factoring into the equation have a very large effect (Josh, certainly the stressors of the dive account for way more than 15 fsw). For me the idea that O2 may be as or more Narcotic than N2 is a stressor, and probably pre-disposes me to be cognizant of my Narcosis. I expect myself to be Narc'd at 85-90 fsw so I find it because I'm looking for it. Back when I first got into diving I thought I was superman at that depth. I'm certain if this was 5 years ago I would have told you that I didn't feel Narc'd at 130.

[BASSMAN]

I expect myself to be Narc'd at 85-90 fsw so I find it because I'm looking for it.

I like this answer!

"Winning!!!"

[kitsapdiver]

Whatevah,

You're response provoked me to go back to my reference, and it does state "the anaesthetic potency of a gas is inversely related to its lipid solubility.".

So you are correct I added the word proportional. Good Catch!

This does get me interested in the science of narcosis, and I am going to take away n action item to go find the publications from the Meyer-Overton study, and read up on current day theory as to why lipid solubility relates to narcotic potency.

Great post whatevah

[Nwbrewer]

....The very next day, I am at 161 feet in about 1/4 knot of current and ended up narced out of my mind while trying to get my breathing back under control.

I think you explained the why here with the 1/4 knot of current. In my experience, CO2 is an UGLY narc.

Please carry on, I'm enjoying the display of SCUBA nerd wisdom.

[Linedog]

As the OP, this thread has given me much more information than I had hoped for. Thank you all who took the time to post, I read every post and anxiously await the next. Thank you again for sharing your knowledge and first hand experience.

[CaptnJack]

why lipid solubility relates to narcotic potency.

Narcosis is actually a fairly broad toxicological term. Generically its basically "stupor" as compared to say excitability. There are literally thousands of narcotic substances but they all act in non-specific ways, i.e. they don't have a target chemical mode of action. In the case of nitrogen and other gases which divers call "narcotic", it dissolves into the lipid fraction of (nerve) cell membranes and disrupts the nerve synapse. You can imagine N2 just barging into the membrane and taking up space that is otherwise needed to function effectively. I don't recall if anyone knows if acetylcholine or noradrenaline based synapses are more or less affected. Maybe there's been more work on this but I doubt it. N2 is not a very profitable research drug.

[LCF]

In fact, the mechanism of action of narcotic/anesthetic gases is very poorly understood. (Think about that, the next time somebody wants to put you to sleep to do something to you!) We know the end effects, and have some ways of predicting what chemical structures are LIKELY to be anesthetic, but nobody knows how they work.

The debate about oxygen will continue to rage, I think; oxygen is a unique gas, in that very little of it is carried in a dissolved state, because it isn't very soluble in aqueous solution. Without hemoglobin to carry the stuff, we would all die of cellular asphyxia. Since we don't know how gases cause narcosis, it really isn't possible to say whether the large quantity of oxygen carried on hemoglobin participates in the narcotic effect that would be predicted by Meyer-Overton, and this is where the controversy has always come in.

What we DO know is that helium is predicted to be far less narcotic than either, and appears to be that in practical use. We also know that CO2 is predicted to be MORE narcotic than either, and that helium improves ventilation mechanics by reducing flow turbulence in small airways, thus allowing someone to do a better job of getting rid of CO2 at any given depth. There is no doubt in my mind that CO2 plays a significant role in some of the narcosis stories people tell. Reducing gas density and improving flow characteristics is almost certainly important in deep diving. Whether there is enough of an effect in the deeper recreational range (100 - 130) to justify the expense and the required skills for diving helium is a good question. I guess if you're narcosis-susceptible and/or are doing dives where attention to detail is important, the answer is probably yes. Otherwise, it's each person's evaluation of his ability to think.

Peter and I were in the water once with a student who was to do his AOW Deep dive . . . but he was so incapacitated by 80 feet that we turned the dive and brought him up shallow. There's no shame in that; it is what it is, and we all set our limits by what we personally are capable of doing.

[pensacoladiver]

....The very next day, I am at 161 feet in about 1/4 knot of current and ended up narced out of my mind while trying to get my breathing back under control.

I think you explained the why here with the 1/4 knot of current. In my experience, CO2 is an UGLY narc.

Yes it is.... get that breathing up a little bit more than normal and take in a bunch more Nitrogen at depth than you normally do and POWWWW!

I need to add, that was during Deco class, trying to get to the Miller Lite while going down a line vice a hot drop.

Since it was class, I did not have the trusty old Dive X Sierra... enough said.

[pensacoladiver]

I have been at 172 FSW just feeling fine and fit as a fiddle... (in truth, I probably wasn't). The very next day, I am at 161 feet in about 1/4 knot of current and ended up narced out of my mind while trying to get my breathing back under control.

Duuuuude, helium is cheap eps. in FL. And double cheap with your own compressor...

This was during Adv Nitrox and Deco class. No helium as of then. On the dive to 161 feet, the instructors plan was to have me breathe off his slung bottle of 21/35 when we got settled on the wreck. By the time I got to the wreck and settled, I had so much damn N2 in me from huffing and puffing to get there, 21/79 would not have done me a damn bit of good. I was already wasted from the N2 I took in on the way. I remember sitting on the wreck puffing away at the Trimix thinking "this shit aint doing nothing for me, I am still looped out of my mind".

Since that time, I have done 1 more deep dive (deep being below 145 feet) on air... to the same wreck... and even though I had the scooter and was not working at all, I was pretty much wasted.

Working on getting the helium setup in the garage now. Just gotta take that first step and buy the $145 bottle full of 300 cubic feet of the good stuff.

[Tom Nic]

it dissolves into the lipid fraction of (nerve) cell membranes and disrupts the nerve synapse.

Boy, I could have used this in High School...

I'm not drunk / stoned, officer, it's just that my nerve synapses are disrupted.

Although... come to think of it, they probably wouldn't have bought that excuse either.

[CaptnJack]

I have been at 172 FSW just feeling fine and fit as a fiddle... (in truth, I probably wasn't). The very next day, I am at 161 feet in about 1/4 knot of current and ended up narced out of my mind while trying to get my breathing back under control.

Duuuuude, helium is cheap eps. in FL. And double cheap with your own compressor...

This was during Adv Nitrox and Deco class. No helium as of then. On the dive to 161 feet, the instructors plan was to have me breathe off his slung bottle of 21/35 when we got settled on the wreck. By the time I got to the wreck and settled, I had so much damn N2 in me from huffing and puffing to get there, 21/79 would not have done me a damn bit of good. I was already wasted from the N2 I took in on the way. I remember sitting on the wreck puffing away at the Trimix thinking "this shit aint doing nothing for me, I am still looped out of my mind".

Since that time, I have done 1 more deep dive (deep being below 145 feet) on air... to the same wreck... and even though I had the scooter and was not working at all, I was pretty much wasted.

Working on getting the helium setup in the garage now. Just gotta take that first step and buy the $145 bottle full of 300 cubic feet of the good stuff.

So would you put adv nitrox and deco with no scooter and current at 160fsw into the "recommended character building" category then?

[Joshua Smith]

I don't want to play scuba cop or anything , but MY adv nitrox and deco card says that I'm certified to do staged deco dives to 150'. Actually, the adv nitrox card says I can use up to 100%02, and the deco procedures card says I can go to 150.

[Jeff Pack]

Does somebody have a watch?

[pensacoladiver]

I have been at 172 FSW just feeling fine and fit as a fiddle... (in truth, I probably wasn't). The very next day, I am at 161 feet in about 1/4 knot of current and ended up narced out of my mind while trying to get my breathing back under control.

Duuuuude, helium is cheap eps. in FL. And double cheap with your own compressor...

This was during Adv Nitrox and Deco class. No helium as of then. On the dive to 161 feet, the instructors plan was to have me breathe off his slung bottle of 21/35 when we got settled on the wreck. By the time I got to the wreck and settled, I had so much damn N2 in me from huffing and puffing to get there, 21/79 would not have done me a damn bit of good. I was already wasted from the N2 I took in on the way. I remember sitting on the wreck puffing away at the Trimix thinking "this shit aint doing nothing for me, I am still looped out of my mind".

Since that time, I have done 1 more deep dive (deep being below 145 feet) on air... to the same wreck... and even though I had the scooter and was not working at all, I was pretty much wasted.

Working on getting the helium setup in the garage now. Just gotta take that first step and buy the $145 bottle full of 300 cubic feet of the good stuff.

So would you put adv nitrox and deco with no scooter and current at 160fsw into the "recommended character building" category then?

Oh, I'm a character alright. If it was a drift dive, it would have been no problem, but swimming into that current to reach an objective.... F that.

[pensacoladiver]

I don't want to play scuba cop or anything , but MY adv nitrox and deco card says that I'm certified to do staged deco dives to 150'. Actually, the adv nitrox card says I can use up to 100%02, and the deco procedures card says I can go to 150.

I knew when I posted my story someone was going to pick up on the depths. I am not going to say who my instructor was, although it is probably posted on the board in another thread, but needless to say, he was very comfortable with taking me to those depths. He also informed me of the class limits and left the choice to me.

OF COURSE I said YES!!! Good lord, it was the Hydro Atlantic. Cant pass that one up.

[CaptnJack]

Oh, I'm a character alright. If it was a drift dive, it would have been no problem, but swimming into that current to reach an objective.... F that.

Do they say hoo ray in the Navy?