Thoughts on letting pts with head injuries sleep

I was working in the back with a medic for a PT who fell and had a beautiful big goose egg on her forehead the other day. Very altered thought it was novemeber, and kept trying ti go to sleep. I kept waking up the patient, but then the other medic said it was beneficial for patients with head injuries to sleep, according to new research. What are your thoughts? My thought is they can sleep when they get to the hospital.