What Causes Body Swelling After Dialysis?

My dad had a massive heart attack and his body went into with then made his organs start shutting down. They can t determine the damage of this heart because. Its to dangerous for them to actually go in and see. His liver and his kidney s are not working he is not producing alot of urine at all. His is currently taking dialysis treatment three times a week. But after his treatment yesterday before we even reached home fluid was already t Starting to swell him up. If dialysis doesnt help or his kidney s or liver don t start working. What do i need to expect or better yet what will happen. He already has so much wrong with him. From diabetes to copd he has a sleep disor he had another heart attack before this in 2007 and for that he had open heart surgery a triple bypass. Please if u could just give me some input I would be so so grateful