As for practical advice I have very little. I hope your cat is an indoor cat as a deaf cat is at an disadvantage when dealing with car and dogs. Avoid startling your cat, as they might nip or scratch you if surprised. Approach it from the front, make sure he/she sees you or feels your footsteps before touching him/her.
I don't know of any hearing aids for animals, but that doesn't mean they don't exist. I sure someone out there is working on them as we speak. However, it is necessary to determine the type of deafness your animal has as it may not be amenable to treatment. Then again you have to consider the cost.
Not much help I'm afraid. Good luck with your elderly friend. I know what it is like, I once had a old blind cat that lived a long happy life.
Actually, that's very helpful. I was thinking there wasn't much I could do as far as treatment, either. It's just that it would be hard to live with myself if I find out in a couple of years that there was something I could have been doing for her all this time.
My kitty, Theresa, doesn't seem to give a damn. She's as happy as ever. (Maybe happier: the vacuum no longer bothers her. :) She is an inside cat, so no worries there. And even when I surprise her, she doesn't get nippy. Just not her nature.
The more I hear some of the unfortunate occurences and illnesses of everyone else's cats, the more grateful I feel about mine. My cat Morris lived 17 years before passing, my cat Theresa is 17 now, and my youngest cat, Baby, is ten years and going strong. (Knock on Spankling's wood.)
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I ate a hooker half a bottle of knife.