Dialysis removes waste and fluids from your body that your kidneys are not able to remove. Without dialysis, the only other option for chronic kidney patients would be a kidney transplant. Otherwise, patients would not survive the build-up of toxins in the blood stream.

Principles of dialysis
There are two main types of dialysis; Hemodialysis and peritoneal dialysis. Whichever treatment is chosen, the aims of dialysis are very similar. Basically, dialysis is designed to replace several functions of the kidney. The therapy must remove excess fluid and waste product whilst also balancing the electrolytes in your body. An effective dialysis requires a semipermeable membrane, blood supply, dialysis fluid and a method of removing excess fluid.

The aim of dialysis
The basic aim of dialysis is to remove waste products, remove excess fluid and correct any chemical imbalance.

Semi permeable membrane
During dialysis a semipermeable membrane separates the blood from the dialysis fluid. This membrane selectively allows certain substances to pass through but not others. It allows for the filtering of waste products into the dialysis fluid and therefore out of the body.

Blood supply
The more blood suppled to the membrane, the more efficient the dialysis treatment. This can be controlled by the dialysis machine.

Dialysis fluid
The dialysis fluid allows for the removal of waste products from the blood. This fluid also contains substances which correct chemical imbalances which may occur as a result of dialysis.

Fluid removal
In hemodialysis the machine uses pressure to pull fluid across the membrane from the blood and into the dialysis fluid. The fluid containing toxic waste substances is drained safely into the main drainage line of the hospital.