More about dialysis – Nahge Clinic

Hemodialysis

Hemodialysis (he-mo-di-AL-uh-sis) is a way to remove waste products from the blood when the kidneys can no longer do their job adequately. In hemodialysis, a machine filters wastes, salts and fluid from the blood. Hemodialysis is the most common way to treat kidney failure.

How does Hemodialysis Work?

In hemodialysis, blood is removed from the body and filtered through a filter called a dialyzer, or artificial kidney, and the filtered blood is returned to the body. To perform hemodialysis, there needs to be an access point in the patient’s body to get the blood from the body to the dialyzer and back into the body. There are three types of access points for hemodialysis: arteriovenous (AV) fistula, AV graft, and central venous catheter (HD cath). The fistula is the most common access used in adult patients and the central venous catheter is the most common access used in children.

When a patient goes to receive hemodialysis, a nurse checks vital signs and gets the patient’s weight. The patient’s weight will indicate how much excess fluid the patient needs to have removed during the treatment. The patient is then connected to the machine.

Blood never actually goes through the dialysis machine. The machine is like a big computer and a pump. It keeps track of blood flow, blood pressure, the amount of fluid removed, and other vital information. It also mixes the dialysate, or dialysis solution, which is the fluid bath that goes into the dialyzer. This fluid helps pull toxins from the blood. The dialysis machine has a blood pump that keeps the blood flowing by creating a pumping action on the blood tubes that carry the blood from the body to the dialyzer and back to the body.

The dialyzer, or filter, is the key to hemodialysis. The dialyzer is a hollow plastic tube about a foot long and three inches in diameter that contains many tiny filters. There are two sections in the dialyzer: the section for dialysate, and the section for the blood.

The two sections are divided by a semipermeable membrane to prevent mixing. The membrane allows the dialysate and waste to pass through, but does not allow blood cells to pass through. The dialysis solution is then flushed down the drain along with the waste. The electrolytes in the dialysis solution help balance the electrolytes in the patient’s blood. Once it is filtered, it is then returned to the patient’s body.

What are the Advantages and Disadvantages of Hemodialysis?

The benefits of hemodialysis include:

Nurses perform treatments for the patient
Regular contact with other hemodialysis patients and staff
Patients usually only have three treatments per week; giving them four days off
No equipment or supplies have to be kept at home
In an emergency, medical help is available quickly

The disadvantages of hemodialysis include:

Travel to a dialysis center may be required three times a week
Patients may not be able to set their own treatment schedule
Permanent access required; usually in the arm for adults and the neck/chest area for children
Needles are required to access a fistula
Access sites run the risk for infection
Strict renal diet and fluid restrictions are required
Some patients experience discomforts such as headaches, nausea, leg cramps, tiredness, and weakness

How do I Prepare for Hemodialysis?

Before hemodialysis begins, your team will need to place an access line (fistula, AV graft, or central venous catheter). The surgical access needs time to heal before you begin hemodialysis treatments. In some cases, an emergency line (central venous catheter) will be placed and used immediately.

If you are doing in-home hemodialysis, you will receive intensive training on what the procedure involves and how to use the equipment safely. You will also meet with a dialysis nurse and nutritionist. It may be a good idea to also have a family member trained to help you. Be sure to find out your new dietary and fluid restrictions with the nutritionist. Visit our ‘Diet and Nutrition’ tab for more information on a renal diet.

Resources:

Home Dialysis Central – Online source of up-to-date, unbiased information about home dialysis—in all its forms—for people with kidney disease, their families, and the healthcare professionals who provide kidney disease care.

American Kidney Fund – Financial assistance and programs for renal patients.

Dialysis Patient Citizens – Nationwide, non-profit, patient-led organization with membership open only to dialysis and pre-dialysis patients and their families.