I talked to Rem's vet this morning. We just talked about what could/should/might happen in the future. She says that I could probably just bring Rem in once about every 3 weeks for a blood test, and we can decide each time whether we need to do anything else. She also said coming in once a week just to test his red blood cells would be fine if I preferred it, and I think I do.
He's had 5 doses of adriamycin, which is 150 out of the max of 240 (measurement not remember--I don't think it's CCs, but maybe) that they'd ever want to give a dog, which is entering the caution zone. She said that by the time they hit 240, most dogs have developed heart problems. So before they give more doses, they'll want to do a measurement of how well his heart is contracting, which they do by ultrasound.
Meantime, we hope for no more bleeding (because they can't give it all that often even in an emergency because of what it does to them) and we test white blood cells to see whether he should be getting antibiotics again. I was thinking about that this weekend while he was grabbing mouthfuls of horse manure, how his white blood cells have been very low every time after the adria.
He's looking happy and healthy today; his appetite's good.