My 84 year old father underwent aortic heart valve replacement 5 days ago - he suffered a complication and had to go back down with a bad bleed for further surgery - this meant he was under anaesthetic for longer than planned and when they woke him next morning he had been intubated for 24 hours - the heart is now apparently working well, but he is suffering from kidney failure, the op was Weds morning with further surgery to stop the bleeding on the Weds afternoon, when we went to see him on Fri morning they had put him on a kidney dialysis machine - late Sunday they said his bowels had begun to work which was a good sign, and that he was starting to produce very small amounts of urine himself - progress was slow, but this was a good sign. However, after reading research on the internet, my understanding is that 60-70% of patients who suffer acute renal failure never come out of hospital, and that those that do, often don't survive more than a year. Can anyone clarify? I know he is old, but the surgeons keep trying to make light of the dialysis, and say they are hopeful the kidneys will get full function back, although no promises. After what I have read on the internet I am very worried, and I know my mom is wishing he never had the surgery at all, can anyone enlighten me please - there don't appear to be any other problems other than that they are helping to maintain his blood pressure at the moment as this went a bit low - he is generally quite lucid and concious, although he is hallucinating a litte if that helps. I would really appreciate any help at all. Thank you.