Val I also don't have a lot of advice but I'm sure Duke will adjust. Dogs rely on so many of thier other senses that it may not effect him as you may think. Maybe when he is sleeping and you want to wake him up you can put a treat by his nose to get his attention in a less shocking way. Remember dogs live for the moment and not the past!! I'm sure both of you will find your way with his new disability. Hang in there Val.