My baby won't latch after his surgery?

Give him so time to heal and you should see your normal baby back again. I am sure at this time his mouth is very painful and he will have to learn how to nurse again. Drinking from the is much different then drinking from a bottle. After he eats from a bottle allow him time to try to comfort nurse. He wont be hungry and will be able to try to nurse/suck without being frustrated because he is hungry. Also try about an hour after giving pain medication.