Dialysis

Hemodialysis removes wastes and water by circulating blood outside the body through an external filter, called a “dialyzer” that contains a semi-permeable membrane. The blood flows in one direction and the dialysate (special dialysis fluid) flows in the opposite; the counter-current flow of the blood and dialysate helps to remove more urea and creatinine from the blood. The undesirably high blood concentrations of potassium, phosphorus, and urea) are constantly replaced by dialysis solution having levels of minerals like potassium and calcium that similar to the natural concentration of healthy blood.

In peritoneal dialysis, wastes and water are removed from the blood inside the body using the peritoneal membrane as a natural semipermeable membrane into a special dialysis solution, called dialysate, in the abdominal cavity which has a composition similar to the fluid portion of blood.

Peritoneal dialysis works slower than hemodialysis, but because it is carried out for a longer period of time the net effect in terms of removal of waste products and of salt and water are similar to hemodialysis. Peritoneal dialysis can be carried out at home by the patient. Although support is helpful, it is not essential. It does free patients from the routine of having to go to a dialysis clinic on a fixed schedule multiple times per week, and it can be done while traveling with a minimum of specialized equipment.