Dialysis

Key points about dialysis

  • Dialysis is a treatment that’s used when your kidneys stop working properly, usually due to chronic kidney disease.
  • It cleans your blood by filtering out waste products and fluid that your kidneys would usually get rid of as urine.
  • While dialysis takes over some of the work of the kidneys it’s not as effective, and it isn’t a cure. 
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Dialysis cleans your blood by filtering out waste products and fluid that your kidneys would usually get rid of as urine. Without dialysis, waste products and excess fluid stay in your body, causing you to feel unwell.

Left untreated, chronic kidney disease is fatal. Dialysis takes over some of the work of the kidneys but it’s not as effective, and it isn’t a cure. 

There are two types of dialysis – haemodialysis and peritoneal dialysis. Haemodialysis is performed outside of your body and peritoneal dialysis is performed inside your body.

Chronic kidney disease treatment options

The following videos from Kidney Health NZ explain the treatment options for chronic kidney disease. These include haemodialysis, peritoneal dialysis, transplantation and supportive care. 

The videos can be found on this Kidney Health NZ resource page(external link) and are available in several languages. 

Haemodialysis (haemo means blood) is a type of dialysis used to treat kidney disease. With this treatment, the blood is filtered outside the body using a dialysis machine (also called a kidney machine). When you “go on the machine” needles connected to tubes are put into a special vein in your arm called a fistula (which is made by a small surgical operation).


The blood flows through these tubes out of your body into a filter (called a dialyser) attached to the dialysis machine and back into your body. Your blood goes round and round through the filter, just as it does with a normal kidney.

The filter cleans the blood and removes the excess water and wastes the damaged kidneys can no longer manage. The fluid made by the filter goes directly down the drain, just like urine.

Most people go on the machine 3 times a week. You sit in a chair and are connected to the machine for 4 or 5 hours each time. Some people have dialysis more often and for a longer time.

There are 3 places where you can have your dialysis treatment – at home (after being taught by hospital staff), at a satellite clinic or at the hospital.

Going on the machine at home makes it easier to continue normal life, but not everyone can manage dialysis on their own. The kidney team will discuss with you which place is best for you.

Deciding which type of dialysis is best for you is something that you and your kidney doctor (nephrologist) will talk about together. Sometimes they may recommend the one that they think will work best for you. This can depend on other medical conditions, family support and lifestyle factors.

Some people choose to do peritoneal dialysis because it can be done at home or at work, while others choose to do haemodialysis because they enjoy having 4 dialysis-free days.

There are advantages and disadvantages to both types of dialysis.

What are the advantages of haemodialysis?

  • Three days a week – four dialysis-free days.
  • Can be performed in hospital by healthcare professionals.
  • If you have a fistula, no external access between treatments.

What are the disadvantages of haemodialysis?

  • Restricted to a chair or bed for each treatment.
  • Fixed schedule – fit your life around treatments.
  • Only allowed to drink small amounts of fluid each day.
  • Some dietary restrictions.
  • Regular trips to the dialysis unit.

What are the advantages of peritoneal dialysis?

  • Performed around your daily activities.
  • Can be done overnight by a machine.
  • Usually able to drink more than if you are having haemodialysis.
  • No needles.
  • Easier to travel – you can take your supplies with you.

What are the disadvantages of peritoneal dialysis?

  • Permanent catheter in your abdomen.
  • Higher risk of infection (peritonitis) due to the frequency of treatment.
  • Can feel uncomfortable carrying extra fluid in the peritoneal cavity.

Decision aids are handouts, websites and tools that can help you work through the advantages and disadvantages of different treatment options such as for chronic kidney failure. Here are a couple you may find useful:

Your nephrologist will talk with you about when they think it’s a good time to start dialysis. Often the decision is based around your kidney function blood tests and how well or unwell you’re feeling.

For further information you can visit this website(external link).

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Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Carmel Gregan-Ford RN, BHSc, National Education Manager, Kidney Health New Zealand

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