What is the primary difference between peritoneal dialysis and hemodialysis?

The primary difference between peritoneal dialysis and hemodialysis lies in the method of filtration used to remove waste products from the blood. In hemodialysis, blood is filtered outside of the body using a specialized machine. This machine acts as an artificial kidney, drawing blood from the body, filtering it through a dialyzer, and then returning the cleaned blood back to the patient.

In contrast, peritoneal dialysis takes advantage of the peritoneum, which is the lining of the abdominal cavity, to filter blood. This method involves introducing a dialysis solution into the abdomen. Over time, waste products and excess fluid move from the blood vessels in the peritoneum into the dialysis solution, which is then drained out, effectively cleansing the blood without using a machine to filter it externally.

This distinction is critical in understanding how each therapy functions and the environments in which they are used. Hemodialysis typically occurs in specialized facilities, while peritoneal dialysis can often be done at home, but the key difference is the mechanism of blood filtration.