It's called cricoid pressure - the logic is to compress the oesophagus (gullet) with your trachea (windpipe) and stop stuff from your stomach coming up and down into the lungs. Also helps bring things into position so the anaesthetist can stick a tube down your throat. Sodium thiopentone classically makes people taste rotting onions. It's used to induce unconsciousness (and in lethal injections too...)
(suxamethonium, Wed 17 Mar 2010, 22:47, 1 reply)

ah!
many thanks to you and lochii.
a bit worrying that it's used in lethal injections, though
( Smash Monkey lowering the tone of the whole internet, Wed 17 Mar 2010, 22:54, closed)

Im glad
those 2 things were explained, i had wondered at how random it seemed
(insomniac-surfer oh go on then, just this once, Wed 17 Mar 2010, 23:24, closed)

it just seemed completely bizarre to me
i've had 20-odd operations, this was the only one to include onions
( Smash Monkey lowering the tone of the whole internet, Wed 17 Mar 2010, 23:39, closed)