My 17 year old sin had a concussion from a knee to the head during wrestling drill on Monday.  He fell on Saturday while skating--face first onto the ice--on Saturday.  He broke his nose.  Has an outpatient surgery scheduled for tomorrow AM to fix the nose.  Is it safe to go under anesthesia?
I read your question and I understand your concern. The main period of danger after a concussion are the first 24 hours during which the patient must be observed. After that period if he is valued as stable there is no particular cause for concern. Anesthesia anyway would not constitute any injury related added risk, and it is safe to be performed. I hope to have been of help.