I'm another who has had a number of CRF cats, both my own and foster. Fluids can bring those astronomical BUN and Creatinine levels down to near normal and sometimes normal with time. If your cat responds to fluids therapy, and your vet appears confident she will, you will be amazed by the difference in her in just a few weeks.

Sam is my current CRF foster and was at death's door when I took her, in fact I made the euthanasia appointment with the shelter for a few days later. Two years later, and through several major scares with viruses, anemia that meant a blood transfusion and then weekly shots of Epogen, she is still going strong and greatly enjoying her life. Her BUN is only slightly over normal, Creatinine is normal, as are Potassium and Phosphorus (you will learn about all these levels as you take care of your Princess.) This is all due to fluids therapy and a good diet (not kidney failure diet but whatever she likes.)

I hope your Princess recovers well and is back with you very soon, complete with all the supplies for you to start her at home subq fluids so you will have her companionship for years to come.