Earlier quoted context omitted.
Looks pretty real to me...they didn't have cgi back in the 40's. However, if they could do that then why wouldn't they still be doing it now with better technology? All a bit morbid for me.
Isn't similar technology used to great extent during difficult surgeries? Where the patient is basically dead and all the life functions such as breathing and blood circulation are performed by machines.
They don't cut your head off during surgeries :-).