Peritoneal dialysis works on the same principle as hemodialysis, but the blood is cleaned inside the body rather than through a machine .Your abdomen has a peritoneal cavity lined by a thin membrane called the peritoneum. That surrounds the intestine and other internal organs .The peritoneal cavity is filled with dialysis fluid that enters the body through a permanently implanted catheter. Excess water and wastes pass through the peritoneum into the dialysis fluid. This fluid is then drained from the body and discarded .The process is repeated between three and five times a day. In most cases this treatment can be performed without assistance, at home or at work.