Character A has just been in a minor car accident, just bad enough to get him into the emergency room but not bad enough that he'd have to be in the hospital for more than a couple days or so. (He drives his car into a tree.) He was driving in his pajamas so doesn't have any insurance or other info on him and he's suffered a concussion so he's not lucid. He has his cell phone on him so the hospital calls Character B because he's listed as an emergency contact on the phone. Character B is not family, just a friend.
The question is this: what would be the protocol for this situation? Obviously they'd want character B to provide insurance information, right? But what kinds of paperwork would he have to fill out? Would the doctors or nurses or whoever talk to him about his medical condition or would they just want him to contact someone who actually was family so they could take it from there? What other regulations, etc., would Character B have to face in this situation? Thanks to anyone who can provide answers!
EDIT: Sorry, I forgot to specify that this takes place in modern-day America, in the Midwest.