Hello & welcome, I am Dr. B, a licensed veterinarian and I would like to help you today. I do apologize that your question was not answered before. Different experts come online at various times; I just came online, read about your situation, and wanted to help.
Again I do apologize that my colleagues could not aid you sooner. If you would still like assistance, can you tell me:
How long ago was he run over?
How long has he been urinating blood? Large urinations or small frequent ones?
What tests did the vet do? Any xrays of the abdomen?
What medications has he been treated with thus far?
Are her gums nice and pink (not white/pale)? Moist or sticky?
If you press on her belly, does she have any tensing, tenderness, discomfort, or pain?