What happens during dialysis
There are 2 main types of dialysis: haemodialysis and peritoneal dialysis.
Haemodialysis
Haemodialysis is the most common type of dialysis and the one most people are aware of.
During the procedure, a tube is attached to a needle in your arm.
Blood passes along the tube and into an external machine that filters it, before it's passed back into the arm along another tube.
This is usually carried out 3 days a week, with each session lasting around 4 hours.
Peritoneal dialysis
Peritoneal dialysis uses the inside lining of your abdomen (the peritoneum) as the filter, rather than a machine.
Like the kidneys, the peritoneum contains thousands of tiny blood vessels, making it a useful filtering device.
Before treatment starts, a cut (incision) is made near your belly button and a thin tube called a catheter is inserted through the incision and into the space inside your abdomen (the peritoneal cavity). This is left in place permanently.
Fluid is pumped into the peritoneal cavity through the catheter. As blood passes through the blood vessels lining the peritoneal cavity, waste products and excess fluid are drawn out of the blood and into the dialysis fluid.
The used fluid is drained into a bag a few hours later and replaced with fresh fluid.
Changing the fluid usually takes about 30 to 40 minutes and normally needs to be repeated around 4 times a day.
If you prefer, this can be done by a machine overnight while you sleep.
Read more about how dialysis is performed.
Introduction 