Hello! I read your question and understand your concern. I would like to know if she had kidney problems before the stroke. The fact that she underwent surgery to reduce brain swelling indicated that she suffered a big stroke, which involved a big part of her brain. It is normal in this condition to be still in coma. The prognosis after a big stroke is poor, and the decompression surgery gives some more chances to be survive. The renal failure complicates more the situation. It may be a complication of multiorgan failure or low blood pressure or an aggravated renal failure after stroke in preexisting low kidney function. Anyway this complication reduced even more the possibilities of recovery. So I would say that the situation is very serious. You can just pray for her to get through this. Best wishes! Dr. Abaz Quka