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Medical Author:

Benjamin Wedro, MD, FACEP, FAAEM

Benjamin Wedro, MD, FACEP, FAAEM

Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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In this Article

• Kidney failure facts
• What are the kidneys?
• What causes kidney failure?
• What are the symptoms of kidney failure?
• How is kidney failure diagnosed?
• What is the treatment for kidney failure?
• Diet
• Medications
• Dialysis
• Hemodialysis
• Peritoneal dialysis
• Kidney transplantation
• What is the prognosis for someone with kidney failure?
• Patient Comments: Kidney Failure - Diagnosis
• Patient Comments: Kidney Failure - Treatments
• Patient Comments: Kidney Failure - Diet
• Patient Comments: Kidney Failure - Symptoms
• Find a local Nephrologist in your town
• Kidney Failure Index

Dialysis cleanses the body of waste products in the body by use of filter systems. There are two types of dialysis; 1) hemodialysis, and 2) peritoneal dialysis.

Hemodialysis uses a machine filter called a dialyzer or artificial kidney to remove excess water and salt, to balance the other electrolytes in the body, and to remove waste products of metabolism. Blood is removed from the body and flows through tubing into the machine, where it passes next to a filter membrane. A specialized chemical solution (dialysate) flows on the other side of the membrane. The dialysate is formulated to draw impurities from the blood through the filter membrane. Blood and dialysate never touch in the artificial kidney machine.

For this type of dialysis, access to the blood vessels needs to be surgically created so that large amounts of blood can flow into the machine and back to the body. Surgeons can build a fistula, a connection between a large artery and vein in the body, usually in the arm, that causes a large amount of blood flow into the vein. This makes the vein larger and its walls thicker so that it can tolerate repeated needle sticks to attach tubing from the body to the machine. Since it takes many weeks for a fistula to mature enough to be used, significant planning is required if hemodialysis is to be considered as an option.

If the kidney failure happens acutely and there is no time to build a fistula, special catheters may be inserted into the larger blood vessels of the arm, leg, or chest. These catheters may be left in place for up to three weeks. In some diseases, the need for dialysis will be temporary, but if the expectation is that dialysis will continue for a prolonged period of time, these catheters act as a bridge until a fistula can be planned, placed, and matured.

Dialysis treatments normally occur three times a week and last a few hours at a time. Most commonly, patients travel to an outpatient center to have dialysis, but home dialysis therapy is becoming an option for some.