I'm a little surprised at the price you paid for a seemingly major operation for Gibson. Vets tend to exploit us with charges for the smallest little things.
We have a Golden Retriever named Shadow (I know... completely inappropriate name) who is starting to get on in his years at 6 and a half.
We have had no major problems yet but I'm dreading something like this happening as he is very close to my wife. Sounds like Gibson is recovering OK from reading your subsequent post, hope he makes a full recovery.