What I suspect happens in books, TV, etc. is that there's some basic research by the writer but no authority on staff who's consulted about whether what the author does with what s/he learned bears any resemblance to reality.
In my first book, I've got a guy who's a bricklayer. I did some research on bricks that are cream colored. I didn't visit a brick yard or talk to masons, just looked online, picked up some info, and used it. It's possible I used it incorrectly, or it wasn't right in the first place. Any masons who read menage erotica could be rolling their eyes at such ignorance on the page, right? The same thing can happen with medicine, or any other area of expertise the general public doesn't have.
I presume, too, that there are times when the medical reality doesn't serve the story. Even if the author knows Josie isn't going to bounce back ready for action in the time remaining, she has Josie do that anyway.