Dialysis performs two functions that the kidneys are no longer able to do – removing excess waste and balancing fluid levels in the body.
Filtering waste products
Excess wastes and water pass from the blood into a special liquid called the dialysis fluid for removal from the body by a process called diffusion.
"My doctor did explain about my options when he told me I needed dialysis. That's the first I'd heard about it. He sent me to an educator and she gave me even more information on my choices." -Richard Colvin, Renal Dialysis Patient
Removing excess fluid
In both haemodialysis and peritoneal dialysis, the process called ultrafiltration removes excess fluid. This process occurs in slightly different ways in haemodialysis and in peritoneal dialysis.
In haemodialysis, the water is simply ‘sucked’ from the blood by the kidney machine. The amount of water to be removed during dialysis can be varied, depending on how the machine is set up.
In peritoneal dialysis a substance (usually glucose) is put into the blood, which ‘sucks’ the water from the blood using a process called osmosis. Peritoneal dialysis solution that contains a lot of glucose will draw off more fluid than a solution that is weaker.
