Our border collie is 14 now and I think she's starting to go deaf, she still barks, but often at inappropriate things, like one of us suddenly speaking.
Our neighbour has a very old dog who is completely blind and deaf, but he still potters about, visits us sometimes. Uses his nose.
It's a problem with your dog if he can't let you know when he wants to go out. Maybe let him out automatically after he's eaten, or woken up from a sleep?
Our collie has a strange ability to use her eyes to make you turn and look at her, even when you don't know she's there, it's sort of hypnotic.