Therapy
Dialysis
Dialysis is a treatment that does the job of the kidneys — filtering waste and excess fluid from the blood — when the kidneys have failed. It can be life-sustaining for people with kidney failure.
Quick answer
Dialysis: what it is, why it's done and what happens
Dialysis artificially removes waste products and surplus fluid from the blood. The main types are haemodialysis (using a machine) and peritoneal dialysis (using the lining of the abdomen).
- Why it is done: It is used when the kidneys can no longer filter the blood adequately (kidney failure), to keep the body's chemistry and fluid balance safe, often while awaiting or instead of a transplant.
- What happens: Haemodialysis usually happens at a unit a few times a week, with blood passed through a filtering machine over a few hours.
What it is
Dialysis artificially removes waste products and surplus fluid from the blood. The main types are haemodialysis (using a machine) and peritoneal dialysis (using the lining of the abdomen).
Why it is done
It is used when the kidneys can no longer filter the blood adequately (kidney failure), to keep the body's chemistry and fluid balance safe, often while awaiting or instead of a transplant.
What happens
Haemodialysis usually happens at a unit a few times a week, with blood passed through a filtering machine over a few hours. Peritoneal dialysis is done at home, using fluid exchanges in the abdomen.
Recovery
Dialysis is an ongoing treatment rather than a one-off; people build it into their routine, supported by the kidney team, diet advice and medicines.
Good to know
Risks and things to consider
Dialysis is life-sustaining but demanding and does not fully replace healthy kidneys. There are risks around access sites and infection, and it affects daily life; a transplant is preferred where possible.
Education and reference only. This explains the procedure in general terms and is not medical advice. Your own care, risks and recovery will be explained by the team looking after you.
Answers
Dialysis: frequently asked questions
What does dialysis do?
It does the kidneys' job of filtering waste and excess fluid from the blood when the kidneys have failed.
How often is dialysis needed?
Haemodialysis is typically done about three times a week for several hours; peritoneal dialysis is done more frequently at home. The kidney team tailors the schedule.
Related
Other therapy
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — procedure and treatment guidance
- Relevant Royal College / professional body
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