No more deep diving deaths

[Majickyl]

No, incidence of HPNS is changed with variation of breathing gas composition. Use of anticonvulsants and 5HT1a receptor antagonists have also decreased incidence in animal experiments.

Is that variation of helium content or of nitrogen content?

 

[smurf doc]

........
Not sure what the Navy divers did, but maybe you need a treatment to relax the larynx first so there is no spasm from inhaling that first amount of liquid?
Would you need a strong tranquilizer first so you don't bail-out from the feeling of panic as you transition from air to liquid in a way like you're chocking on a drink?

When they can make it work, I'll be the first one to try.

Would be keen to learn more. Does anyone have any references to actual Navy research studies on this?

I just found this thread. Underwaterfrank I am thinking along the same lines you are -- nerve blocks or nebulized local anesthetics + transtracheal nerve block. But you would have to use long acting agents.

However, if you have to cannulate a vein anyway, instead of having a scrubber, why not use a membrane oxygenator also, like in cardiac bypass?

If you are going to cannulate the femoral vein, then it would have to be a long cannula to allow for movement at the thigh without coming out, and it would have to be sutured in place.

I think someone else already mentioned the vision issue -- need an air interface.

I think others have mentioned concerns about oxygen toxicity -- you and contents may be sealed, but you are still under pressure.

Just typing my thoughts on the subject -- interesting but not practical.

 

[underwaterfrank]

As feeding the oxygen supply via vein is of course a valid option in theory, you still can't send a diver down hundreds of feet if there is residual air in the lung. Just like an extreme version of freediving your lungs will compress further and further, causing fluid shifts from the blood into the lung and resulting damage, so even with oxygen feed in a vein, you need to fill the lung with a non-compressible material, so a fluid is needed in any case.
So in any case, the diver would need to be able to tolerate a filling of the lungs, and then get through the stage of draining the fluid out again afterwards.