If your father has been in the hospital
for 3 weeks with liver failure and his
ammonia is still this high, it sounds pretty grim to me. Of course, I'm basing this on very limited information, and your father's doctors have the whole picture in front of them, so again, talk to them. Ask them point blank, "do you think my father is about to die?'
As stated above, high ammonia levels cause "encephalopathy", extreme lethary and confusion.