Dialysis is the process of filtering the accumulated waste products from the blood of a patient whose kidneys are not functioning properly, using a dialysis machine. Dialysis treatments replace some of the kidney’s functions through waste removal and fluid removal.

In hemodialysis, the patient’s blood is pumped through the blood compartment of a dialysis filter called a dialyzer, exposing it to a partially permeable membrane. The dialyzer is composed of thousands of tiny synthetic hollow fibers. The fiber wall acts as the semi-permeable membrane. Blood flows through the fibers, dialysis solution flows around the outside of the fibers, and water and wastes move between these two solutions. The cleansed blood is then returned back to the body.

In the US, hemodialysis treatments are typically given in a dialysis center three times per week

Posted in: Definitions