kidney failure. my dad is gaining 3-6pounds of fluid a week.

my dad has been a diebetic for 10+yrs. he alsfao has congestive heart failure and emphasyma and copd. last week doctor told him he was in kidney failure and there was nothing else they could do for him. he is gaining 3-6pounds of fluid a week. that wont come off. just keeps swelling all the time in his legs feet and ankles. now also in his face. please what does this mean. how long can he survive like this with no treatmeant?