What is dialysis?
Principles of dialysis
Dialysis removes the waste products and extra fluid from your blood by filtering them through a membrane/filter, similar to the way healthy kidneys would. During dialysis, blood is on one side of the membrane/filter and a special fluid called dialysate (containing water, electrolytes, and minerals) is on the other. Small waste products in your blood flow through the membrane/filter and into the dialysate.
The 3 principles that make dialysis work are diffusion, osmosis, and ultrafiltration.
Diffusion
During diffusion, particles in the areas of high concentration move toward the area of low concentration. Picture how a tea bag works—the leaves stay in the bag, and the tea enters the hot water. In dialysis, waste in your blood moves toward dialysate, which is a drug solution that has no (or very little) waste. How much waste is removed depends on the size of the waste, the size of the pores (holes) in the membrane, what’s in the dialysate, and—like a tea—the length of treatment.1
Osmosis
During osmosis, fluid moves from areas of high water concentration to lower water concentration across a semi-permeable membrane until equilibrium is reached. In dialysis, excess fluid moves from blood to the dialysate through a membrane until the fluid level is the same between blood and dialysate.
Ultrafiltration
Ultrafiltration is the removal of fluid volume from a patient. In dialysis, ultrafiltration removes waste and excess fluids from the blood.2
Your Dialysis Journey video
What is peritoneal dialysis (PD)?
PD uses a special solution (dialysate) and your own peritoneal membrane—the lining of your abdomen—as the filter to help clean the blood and remove excess fluids. This method is similar to regular kidney function insofar as the blood cleansing and fluid control is continuous inside your body.
What is hemodialysis (HD)?
HD is a type of dialysis that filters your blood outside your body using a machine and a dialyzer, which is a manufactured filter that is referred to as an artificial kidney.
Learn more about dialysis
Which dialysis is right for me?
The 2 types of dialysis are peritoneal and hemodialysis. There may be medical or lifestyle reasons for why one type of dialysis best fits you.
Where can I do dialysis?
You can do dialysis in the hospital/clinic setting with in-center HD, or you can dialyze at home or on the road with PD. Some patients have the potential to do home HD.
Dialysis access
An access needs to be created surgically on your body for dialysis. Whether PD or HD, the location and type of the access site is different.
What to expect
Get a better understanding of what to expect with PD and in-center HD. Consider which type of dialysis is best for you.
Comparative chart
There are different benefits and considerations for PD and in-center HD. Understand all the treatment options and how they might impact you.
Curious about your treatment options?
Take the quiz to find out if PD is the right fit for you.
