If the hospital will allow the kids to his room, I see no problem with it. Just be honest and basic telling the kids daddy is "sick" and will be home when he is better. Just keep the visit(s) short for hubby's sake. If he's feeling weak he may need to have some quiet time and also the other patients as well may be too sick and weak to tolerate children for too long. If the hospital will not allow the kids up due to their age, make arrangements to have someone meet you at the front desk to take his charger to him. Or you can even just have the phone in his room turned on too.
But keep one thing in mind, the hospital is full of sick folks and you actually may be better off keeping the kids away from there if possible. Especially with the N1H1 Flu right now.
Good luck,
M. in Camden, MI