Dialysis

Dialysis is a medical treatment that filters and purifies the blood using a machine to keep your body in balance when the kidney can't do its job properly. This treatment is necessary for individuals with end-stage renal disease (ESRD) or acute kidney injury.

Types of Dialysis

  • Hemodialysis: This type of dialysis uses a machine to filter the blood outside the body. The patient's blood is pumped through a dialyzer, which removes waste products and excess fluids, before being returned to the body.
  • Peritoneal Dialysis: In this type of dialysis, a special fluid called dialysate is infused into the patient's abdominal cavity through a catheter. The peritoneum, a membrane in the abdomen, acts as a filter to remove waste products and excess fluids from the blood.
  • Continuous Renal Replacement Therapy (CRRT): This type of dialysis is used for critically ill patients who require continuous removal of waste products and excess fluids. CRRT is typically performed in an intensive care unit (ICU) setting.

How Dialysis Works

Dialysis works by using a semipermeable membrane to separate the blood from the dialysate, allowing waste products and excess fluids to pass through while keeping beneficial substances, such as proteins and blood cells, in the bloodstream. The dialysate is formulated to match the body's natural chemical balance, helping to restore normal electrolyte levels and acid-base balance.

Indications for Dialysis

  • End-stage renal disease (ESRD)
  • Acute kidney injury
  • Poisoning or overdose
  • Fluid overload
  • Electrolyte imbalance

Benefits and Risks of Dialysis

The benefits of dialysis include:

  • Removal of waste products and excess fluids from the blood
  • Correction of electrolyte imbalances
  • Improvement in symptoms such as fatigue, nausea, and vomiting

The risks of dialysis include:

Dialysis Access

To undergo dialysis, patients need a way for the dialysis machine to access their bloodstream. The most common types of dialysis access include:

  • Arteriovenous Fistula (AVF): A surgically created connection between an artery and a vein in the forearm.
  • Arteriovenous Graft (AVG): A surgically implanted tube that connects an artery and a vein in the forearm.
  • Catheter: A tube inserted into a large vein in the neck or chest to access the bloodstream.

Dialysis Frequency and Duration

The frequency and duration of dialysis sessions vary depending on the individual patient's needs. Typically, hemodialysis is performed three times a week for 3-4 hours per session, while peritoneal dialysis can be done continuously or in cycles throughout the day.

Frequently Asked Questions (FAQs)

What is dialysis?
A treatment that filters waste products from the blood when kidneys are not functioning.

Why is dialysis needed?
To replace kidney function in patients with end-stage renal disease or acute kidney injury.

What are the types of dialysis?
Hemodialysis and peritoneal dialysis.

How often is dialysis performed?
Typically 3 times a week, for 3-4 hours per session.

Can dialysis be done at home?
Yes, with peritoneal dialysis or home hemodialysis.

What are the risks of dialysis?
Infection, low blood pressure, and blood clots.

How long can someone live on dialysis?
Varies, but average life expectancy is 5-10 years.

Can dialysis be stopped?
Only with a kidney transplant or if kidney function improves.

Is dialysis painful?
Generally not, but some discomfort may occur during the procedure.

Can patients on dialysis travel?
Yes, with planning and arrangements for dialysis at their destination.

Article last updated on: 25th June 2025.
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