I had a recent talk with a long-time friend who is an RN at a hospital in my home town. She told me all of the proper hospital procedures that would be followed in the common trope: boy wakes up in hospital a girl

Among them:
-A person who has been "unconscious" for longer than an hour is not "unconscious" they are comatose. Not, "You were knocked out for two days" but, "You've been in a coma for two days."

-A person in a coma is kept in the ICU, hooked up to: a pulse oxymetor, an IV drip, a catheter, an EEG, and an EKG. They'll have massaging pads on their legs to prevent bloodclots

-The doctor will try to put off putting a feeding tube in for as long as possible, so blood tests for nutrition levels are run everyday. When they start getting low (maximum of a week and a half) they'll install a feeding tube.

-A person who comes into the hospital comatose is immediately subjected to a battery of tests to ascertain what trauma caused it, how threatening that trauma is, and correct it if at all possible. For example, a comatose patient with head trauma might be at risk of a brain swell which will leave them a vegetable unless steps are taken immediately, or they might need an operation to correct a brain bleed. So an MRI of their head would be the first thing they would get. Then CT scans of their body. Electrocardiogram of the heart, liver and spleen. In a case where the trauma that induced the coma is unknown the patient would get a full body MRI, complete blood panel, and a sonogram of all of her organs, and bowel. In the case where a person had, for unknown reasons, swapped genders, they would do every test known to man, make up some more tests, do them, and then transport the patient to another hospital with different equipment, do all those tests there, then make up even more tests, and do those.

-When you come out of the coma, there is a nurse in the room with you. No one is ever surprised to see you awake, because your brain is hooked up to the EEG, and they can see when you're close to regaining consciousness and send a nurse in.

-When an unidentified minor (*edited) is in the ICU, there is a security guard outside their door at all times.

-When a minor is in the hospital and no one can reach their parents, or the child is unidentified, a CPS case is immediately opened. A CPS case worker will be assigned to determine if a criminal investigation is warranted. Either way, the child will be seeing a LOT more of that CPS worker.

-When a minor has been in a traumatic accident, their parents or guardian will have met with a child psychologist to discuss how to break the news to them. That psychologist will be in the room when the child wakes up, if the parents are there too, and they'll be there when the parents decide a break the news if they have to put it off. The staff will avoid any discussion with the minor about how and why they are in the hospital until someone the child trusts can tell them.

(Unless the child is an emancipated minor (16 and up) anyone under the age of 18 is a minor, and all of those thing apply)

Hope that helps. If you have any other questions about hospital procedures I can bring them up for her as well.