My sensory dd would probably want to try the headphones and having access to her music. Can you stay in the room with him at night or do you have to leave? Can you bring in comfort food for him or does he have to stay on the hospital diet?
The one thing I'd insist on if it's at all possible is *no* interruptions at night from hospital staff. When my ds was born, people came in to our room in the middle of the night to do things that could absolutely have waited until daylight and waking hours and it annoyed the heck out of me. I was in the hospital for several days after he was born, and I finally had it figured out by the time I left - the reason they were sending nurses in to check on things in the middle of the night was simply because those nurses didn't have much to do and it was the hospital's way of spreading work around among nurses evenly.
I don't know if it would help, but you could ask for your ds to have a chance to visit the hospital and a similar room to where he will be staying before he is admitted - that might give him a chance to let you know what he thinks might be an issue for him and you could have a chance to brainstorm together ways to deal with it.
Do you think he'll feel like having company?
That's all I can think of at the moment - I will be thinking of your ds - hospital stays are stressful for anyone, and I can only imagine how much more stressful sensory issues could make them.
Best wishes,
polarbear