The most common type of peritoneal dialysis. It needs no machine. With CAPD, the blood is always being cleaned. The dialysis solution passes from a plastic bag through the catheter and into the abdomen. The dialysis solution stays in the abdomen with the catheter sealed. After several hours, the person using CAPD drains the solution back into a disposable bag. Then the person refills the abdomen with fresh solution through the same catheter, to begin the cleaning process again.