Dilaudid is awful stuff, meaning it could cause hallucinations.
Be prepared for a sensory onslaught.
I've spent a LOT of time in hospitals as a patient. My mum was just in hospital for five weeks. They gave her Dilaudid and she thought she was in a drug den in New Orleans. She also got really itchy from it.
The worst of it for me is the sensory disruption, like beeping machines, bright lights, interrupted sleep, bad mattresses, bad pillows, uncomfortable gowns, noisy staff in the hallway, nasty smells, etc. It drives me nearly insane.
I'd recommend taking as many familiar products as possible - his pyjamas, slippers, sheets, blankets, pillows, towels for sponge baths, his own skin care products, etc. Some people even take a foam mattress topper if that's allowed. Take familiar things from home that he can touch or look at, like photos, books, or knick-knacks --- not a bunch of new balloons or flowers. I always pack a sensory toolkit of things I'll want to smell to help calm me (I'm into PlayDoh), and a little CD player or radio with music I like (I guess today people would use their phone with earphones but I don't do that). Earplugs to block the beeping machines. A dim table lamp. A blindfold for overhead lights at night if needed. Something to cuddle like a comfort object. A fidget ring or object. Something to occupy his mind like a rubix cube or book of puzzles.
Also, let the hospital know he has SPD (Sensory Processing Disorder) and see what else they can accommodate. Usually they can shut off the beeping noises and put the patient in a quieter area with better lighting.
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