Been there, done that. There will be no making it easy with all the sensory hell (constant invasive touching, endless interruptions, to check on him, lighting etc) and just not feeling well from the surgery and medication.
I brought an IPAD and spent every moment not being interrupted or sleeping pursuing my interests. He should make sure there is stuff stored on his device in case the internet is sketchy. You can tell them in advance about his Aspergers/mild autism. Knowlege is increasing about ASD but don't assume they will know much. You have to fill in the details about his particular sensitivities. I have disclosed to medical personnel and usually it goes in one ear and out the other, they are focused on what health problem they are trying to solve but I did have a nurse with an Aspie brother so you never know.
It is important you be an advocate. Whatever social communication difficulties he has will be enhanced by all the stress but you somehow have to find a way to do that without infantilizing him.
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Professionally Identified and joined WP August 26, 2013
DSM 5: Autism Spectrum Disorder, DSM IV: Aspergers Moderate Severity.
“My autism is not a superpower. It also isn’t some kind of god-forsaken, endless fountain of suffering inflicted on my family. It’s just part of who I am as a person”. - Sara Luterman