H.A.
My daughter has been sedated several times... for a biopsy, an MRI and then an unrelated surgery. Her first time was right around 9-10 months.
For her MRI... They gave her a nasal spray and had me hold her, the spray was like Valium, to relax her about being taken from me. It made her feel drowsy and very content. They wheeled her back to be sedated. I was not there to actually see her go under (they didn't allow it.) They told us they would call us back after she was awake and warned us that every child is different - some cry when they come out of sedation because its disorienting. Our daughter didn't cry. She was quiet, sleepy and cuddly, just kind of sitting back taking it all in.
Truthfully I was much more upset by it then she was.
Once he comes home your experience may be different depending what kind of sedation he had. They could tell you clear liquids or light foods if its something that will keep them drowsy. Nothing too heavy on the tummy. We got some apple juice and let her have that in a bottle, she was still primarily nursing at the time - so it wasn't a big deal meal wise. She doesn't usually watch TV, but when we got home I put a little Baby Einstein on for her to sit and watch. I know for my own peace of mind I had her nap near me. I pulled the pack n play out and had her in the living room. It just made me feel better to be able to watch over her during her nap time that day. For all my concern she really had a very easy recovery from the sedation.
I know you can't help but worry, I hope your day will be as uneventful as our experience was.