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The anesthetic effect of air at atmospheric pressure

pubmed.ncbi.nlm.nih.gov

11–20 of 205 posts

Re: The anesthetic effect of air at atmospheric pressure

#11

What if instead it's helium that is a slight stimulant?

Essentially true by definition. If something is the norm then replacing that norm with helium and seeing enhanced performance isn't signal of the norm being restrictive. It's signal of helium being performance enhancing.

Re: The anesthetic effect of air at atmospheric pressure

#13

What if instead it's helium that is a slight stimulant?

The effect of nitrogen varies with its pressure, i.e. with its concentration, while no changes are seen when the helium pressure is varied.

This allows the conclusion that nitrogen has anesthetic effect and helium does not have stimulant effect.

Because it appears that the anesthetic effect of inert gases depends on their molecular mass, being much stronger for heavy gases like xenon, it is possible that helium also has an anesthetic effect, but one that becomes noticeable only at higher pressures than can be safely tested.

Re: The anesthetic effect of air at atmospheric pressure

#14
post #3

The action potential is an electrical manipulation of reversible abrupt phase changes in the lipid bilayer. Normally the lipid bilayer is in a liquid phase but the the switching out of monovalent sodium for bivalent calcium ions changes the number of phospholipid carboxyl head groups each ion is electrostatically associated with. This changes the heat capacity and causes the lipid membrane to become a solid/gel phase…

Are you saying that what's happening is the permeability of the cell membrane changes with their physical states (from a scale of "more liquid" to "more solid")and that change impacts the transmission rate of the neurons? And an example of this would be an anesthesiologist putting you under is them making your cell membrane more solid to increase the resistance those neuron transmissions experience, just like adding more resistance to a circuit to reduce the voltage?

Disclaimer that biological sciences aren't my strength so I'm just trying to understand what you're saying.

Re: The anesthetic effect of air at atmospheric pressure

#15
post #3

The action potential is an electrical manipulation of reversible abrupt phase changes in the lipid bilayer. Normally the lipid bilayer is in a liquid phase but the the switching out of monovalent sodium for bivalent calcium ions changes the number of phospholipid carboxyl head groups each ion is electrostatically associated with. This changes the heat capacity and causes the lipid membrane to become a solid/gel phase…

Mm-hmm, Mm-hmm... Oh! Oh, yeah... mm, mm. Mmm!

I know some of these words!*

More seriously - thanks for that description! It's always interesting to see just how many "principles" &/ "laws" etc. (our compartmentalized / simplified models) underlie certain kinds of physical behavior (and, sort of, emergent properties thereof). Even just sticking together enough of the simplest models can be kind of surprising and not so easy to reason about / handle with much "facility".

I've never learned much about anesthesia, and the little bits I have learned, here and there - and usually only in very specific contexts, makes it so most of this info doesn't really stick in my head. So, I appreciate getting a bit of refresher / learning every now and again. Particularly, in how it ties together with everything else involved.

Thanks!

* https://youtu.be/sl2W85KKzgc

Re: The anesthetic effect of air at atmospheric pressure

#16
post #3

The action potential is an electrical manipulation of reversible abrupt phase changes in the lipid bilayer. Normally the lipid bilayer is in a liquid phase but the the switching out of monovalent sodium for bivalent calcium ions changes the number of phospholipid carboxyl head groups each ion is electrostatically associated with. This changes the heat capacity and causes the lipid membrane to become a solid/gel phase…

Are you saying that what's happening is the permeability of the cell membrane changes with their physical states (from a scale of "more liquid" to "more solid")and that change impacts the transmission rate of the neurons? And an example of this would be an anesthesiologist putting you under is them making your cell membrane more solid to increase the resistance those neuron transmissions experience, just like adding…

No, it's not about ions going through the membrane or membrane pemeability. It is not about resistance to ions flow across the 10nm they travel perpendicular to the membrane. Transport of ions across through ion channels are required for the effect but the membrane itself (usually) is not leaking and I'm not talking about changes in leakage.

It is about how the various ions like Na+ and Ca+2 associated with the membrane itself to change the membrane's physical properties. When there's lots of light gas anesthetic dissolved in the lipid membrane keeping the heat capacity low (disordered) it is thermodynamically harder (requires more energy) to form the organized 'solid' (actually more like a gel) state that propagates as the action potential.

ref: https://arxiv.org/abs/1805.11481 - good overview paper, http://erewhon.superkuh.com/library/Neuroscience/Lipid%20Mem... - other papers/books on the subject.

Re: The anesthetic effect of air at atmospheric pressure

#17
post #7

I wonder how much it would cost to fill my office with helium/oxygen mix to maximize my productivity. Would sound odd during calls, though!

> Would sound odd during calls, though!

I find myself thinking how you might dress or act to disguise it, and then this climactic (i.e. spoiler) scene from "Who Framed Roger Rabbit", and finally anxiety about the weird places my mind goes.

https://www.youtube.com/watch?v=BDrqCq4fGRE&t=73s

Re: The anesthetic effect of air at atmospheric pressure

#18
post #7

I wonder how much it would cost to fill my office with helium/oxygen mix to maximize my productivity. Would sound odd during calls, though!

Although it's clear you are being facetious, let's see where it goes. I would surmise the best and most economical gas mix to breathe long term at ambient pressure would be somewhere between 80/20 and 75/25 mix of Argon/Oxygen.

Re: The anesthetic effect of air at atmospheric pressure

#20

I wonder if there's a cheaper filler gas we could use besides He. Perhaps methane, hydrogen, or acetylene, though they're quite flammable.

I don't know if you've ever taken a good whiff of acetylene, but I would hate to have to live off it (maybe is it truly odorless, and its just common contamination?)
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