Yes - all of the above. The amount of time for xrays and the type of anesthesia are typically vastly different.
I had a dog neutered and he was anemic, so she used a different anesthesia, he recovered so quickly from it, that they called me at 2 and said please come get your dog, he keeps breaking out of his kennel and the last time was running through the surgery suite...sooooo....what could have been bad, had they not known, turned out to be a fun day for my dog.
I also have them do a buccal muccosal bleeding time test. It's not as good as a clotting factor test, it's not going to show why a dog is bleeding faster than normal or slower, but it's going to get an idea of their bleed rate, which is important in GSDs and their mixes. https://ahdc.vet.cornell.edu/sects/c...l/bleeding.cfm https://ahdc.vet.cornell.edu/clinpat...coags/bmbt.htm
If a dog hasn't had a heartworm test in a year or more, I'd do that as well before, plus you get the bonus of the tick tests.
No supplements a week before surgery - fish oil, joint, whatever. I let them know what the dog has been on prior - this includes if you use natural things - stuff like Turmeric, flaxseed, etc, can impact bleeding. Also important of course are things like regular medications.
DogAware.com Health: Caring for Dogs Before and After Surgery
I do this any time I can before a surgery. Good question!