Right now, I'd stop bathing him. His skin needs a rest and recover period. Can you get a syringe and force feed him?? I had to do that once after surgery to get him going on eating again. It is imperative that he is hydrated. Their bodies are so tiny that dehydration can set in very quickly. If he's not taking any fluids he may need to have SUB-Q fluids and your vet will need to do that.