Hemodialysis

Treatment Overview

Chronic kidney disease and acute kidney injury (also known as acute renal failure) cause the kidneys to lose their ability to filter and remove waste and extra fluid from the body. Hemodialysis is a process that uses a man-made membrane (dialyzer) to:

• Remove wastes, such as urea, from the blood.
• Restore the proper balance of electrolytes in the blood.
• Eliminate extra fluid from the body.

For hemodialysis, you are connected to a filter (dialyzer) by tubes attached to your blood vessels. Your blood is slowly pumped from your body into the dialyzer, where waste products and extra fluid are removed. The filtered blood is then pumped back into your body.

There are different types of hemodialysis. Talk about these with your doctor to decide which one might be best for you.

• In-center hemodialysis. You go to a hospital or a dialysis center. Hemodialysis usually is done 3 days a week and takes 3 to 5 hours a day.
• Home hemodialysis. After you are trained, you do your dialysis treatments at home. Hemodialysis is usually done 3 days a week (or every other day). Discuss with your doctor how long each session needs to be. A session could be as long as 6 hours, which may help you feel better.
• Daily home hemodialysis. After you are trained, you do your dialysis treatments at home. Hemodialysis is done 5 to 7 days a week. Each session takes about 3 hours.
• Nocturnal home hemodialysis. After you are trained, you do your dialysis treatments at home. Hemodialysis is done 3 to 7 nights a week. Each session is done overnight (about 6 to 8 hours).

Before treatments can begin, your doctor will need to create a site where the blood can flow in and out of your body during the dialysis sessions. This is called the dialysis access. The type of dialysis access you have will depend in part on how quickly you need to begin hemodialysis.

There are different types of access for hemodialysis:

• Fistula. A fistula is created by connecting an artery to a vein in your lower arm. A fistula allows repeated access for each dialysis session. It may take several months for the fistula to form. A fistula may not clot as easily as other dialysis access methods. A fistula is the most effective dialysis access and the most durable. Complications include infection at the site of access and clot formation (thrombosis).
• Graft. A vascular access that uses a synthetic tube implanted under the skin in your arm (graft) may be used if you have very small veins. The tube becomes an artificial vein that can be used repeatedly for needle placement and blood access during hemodialysis. A graft does not need to develop as a fistula does, so a graft can sometimes be used as soon as 1 week after placement. Compared with fistulas, grafts tend to have more problems with clotting or infection and need to be replaced sooner. A polytetrafluoroethylene (PTFE or Gore-Tex) graft is the most common type used for hemodialysis.
• Venous catheter. A tube, or catheter, may be used temporarily if you have not had time to get a permanent access. The catheter is usually placed in a vein in the neck, chest, or groin. Because it can clog and become infected, this type of catheter is not routinely used for permanent access. But if you need to start hemodialysis right away, a catheter may be used until your permanent access is ready.

Hemodialysis for acute kidney injury may be done daily until kidney function returns.

Choosing between treatment with hemodialysis or peritoneal dialysis is based on your lifestyle, other medical conditions, and body size and shape. Talk to your doctor about which type would be best for you.