Exactly what it sounds like. Fecal matter from a healthy person, transplanted into the GI system of an unhealthy person. Benefits come from all the "good bacteria" living in there that are missing.
YouTube has some deliciously informative videos if you'd like to watch a real surgery!
I'm not incredibly familiar, but I watched some of those tasty videos I referenced. It certainly looked like there was somebody in there unconscious, with a Dr gowned up. Tubes and cameras and robot arms inserting various things.
Depends where you draw the line at surgery VS procedure, does something have to be cut? Who knows! Either way, I recommend not DIY'ing this one.
YouTube has some deliciously informative videos if you'd like to watch a real surgery!