Trying to help out my son so these are the best facts I have about it
In an insane asylum (not Session 9)
Guy is in an iron lung and they pour eels in his throat (not Eels)
Some guy is almost dead and they throw him in a vat of electric eels and he comes back to live (not that Spiderman with Jamie Foxx)
Newer than 2001 and has people in it that have been in other things.
A Cure for Wellness? It takes place in an asylum (although not really for the insane), and there are a bunch of eels. The eels prolong people’s lives, so I guess you say a guy comes back to life?
It definitely has people in it that have been in other things.
Does it have a guy in an iron lung? He was very specific about that plot point.
I’ve not seen it, but it has IMDB keywords “iron lung” and “eel”. So it sounds like a likely match.