Hemodialysis

Hemodialysis is a type of dialysis that filters your blood to remove waste products and excess fluids. Your kidneys are part of your urinary system. Healthy kidneys filter your blood and make pee. But if they don’t work properly, dialysis does the work for them.

During hemodialysis (hee-moh-dahy-AL-uh-sis), a machine removes blood from your body. It filters your blood through an artificial kidney (dialyzer) to remove waste and fluid. It then returns the cleaned blood to your body.

You may need hemodialysis if you have very damaged kidneys that can no longer clean your blood properly. This usually happens in late-stage chronic kidney disease (CKD) or kidney failure. You may also need it if you’re waiting for a kidney transplant.

Hemodialysis (or haemodialysis) is the most common type of dialysis. Most people who need dialysis receive hemodialysis.

How does hemodialysis work?

The dialyzer is the part of the hemodialysis machine that filters your blood. Your blood flows through tiny mesh tubes inside the dialyzer’s core. Waste products and excess fluids in your blood pass through the mesh tubes into dialysate. Dialysate is a fluid that consists of water, salts and electrolytes.

Your filtered blood returns to your body. The dialyzer then gets rid of the dialysate. The dialysate has your blood’s waste products and excess fluid.

What are the types?

There are two main types of hemodialysis. Your healthcare provider will review them and recommend the best type for you. They include:

In-center hemodialysis

For this type, you go to a healthcare facility that specializes in providing hemodialysis. A hemodialysis nurse or technician performs the procedure.

Most people get in-center hemodialysis at least three times per week. Each session takes between three and four hours.

Home hemodialysis

This type takes place in your home. Over several weeks or months, your healthcare providers will teach you how to perform hemodialysis. They’ll also teach you how to fix common problems that may occur. You then perform hemodialysis yourself, on your own schedule.

There are three types of home hemodialysis:

• Conventional home hemodialysis: You perform conventional home hemodialysis three times a week. Each session lasts at least three to four hours.
• Short daily home hemodialysis: Short daily home hemodialysis uses new technology that allows for shorter sessions. You perform hemodialysis five to seven days a week. Each session lasts around two hours.
• Nocturnal (overnight) home hemodialysis: This type takes place while you’re asleep. You perform hemodialysis four to six days a week. Each session lasts between six and eight hours. This type removes more waste from your blood. You spend more hours each week on nocturnal dialysis than on the other types.

What happens before hemodialysis?

You must prepare for your first hemodialysis session weeks or even months in advance.

If you can do hemodialysis at home, your provider will teach you how to properly perform it. They’ll also go over some common problems.

You’ll first have a minor surgery to make it easier to access your bloodstream. You may have one of the following procedures:

• Dialysis fistula: Your surgeon connects an artery and vein in your arm.
• Dialysis graft: If the artery and vein in your arm are too short to connect, your surgeon will use a soft, hollow tube (graft) to join them.

These procedures make the connection between your artery and vein easier to access during hemodialysis. They also help your blood flow in and out of your body faster.

In some situations, you may need to start hemodialysis quickly. Your provider may insert a temporary soft tube (catheter) into a vein in your leg, chest or neck.

Your provider will teach you how to clean your fistula or graft to prevent infections and feel for the vibrations (thrill) to ensure the access is working. They’ll also show you how to protect your fistula or graft. If you accidentally damage it, you may no longer be able to use it for hemodialysis.

What happens during treatment?

Your hemodialysis nurse or technician will put two needles in your arm. Soft tubing connects both needles to the hemodialysis machine.

If you’re on home hemodialysis and have proper training, you may put the needles in yourself.

The hemodialysis machine:

1. Removes blood from one of the needles in your arm
2. Circulates your blood through the many mesh tubes in the dialyzer
3. Moves excess waste and fluids into a dialysate solution
4. Returns your filtered blood to your body through a second needle in your arm

During your hemodialysis session, the machine regularly monitors your blood pressure.

Is it painful?

You may feel a slight pinch when the needles enter your fistula or graft. The needles are 15- or 16-gauge. They’re bigger than the needles that providers use for blood tests. The outer diameter of a 15-gauge needle is about 1.8 millimeters (mm). That’s about 2.5 times larger than the tip of a ballpoint pen. The outer diameter of a 16-gauge needle is slightly smaller — about 1.65 mm. But the hemodialysis process itself shouldn’t cause any pain.

Why does it take so long?

Healthy kidneys work nonstop to filter your blood. They filter your blood even while you sleep. But even with advances in treatment, hemodialysis isn’t as efficient as healthy kidneys.

Healthy kidneys filter about 150 quarts of blood in a single day. Hemodialysis is only about 5% to 10% as effective as healthy kidneys.

What happens after?

You or your provider will remove the needles, apply pressure on the needle access site to stop it from bleeding and then clean your access areas. You may continue your everyday activities.

Many people feel tired or sick after hemodialysis sessions. Your symptoms may last a few hours. But others report having more energy with more frequent hemodialysis.

What are the potential benefits and risks of this treatment?

The main advantage of hemodialysis is that it does the work of your kidneys when they no longer can. Without it, toxins will build up in your blood (uremia). Uremia is fatal without treatment. Filtering out toxins that build up in your blood also helps many people feel better.

Another advantage is that sessions are usually only three times each week.

You may decide when and where to have your sessions for home dialysis. You may even choose to have your sessions overnight. Nocturnal home hemodialysis allows you to maintain a more consistent daily routine.

Hemodialysis also has some risks. Some people may have complications with their fistulas or grafts. These may include:

• Infection
• Scar tissue that causes a hemodialysis access blockage
• Blood clots in the fistula or graft that won’t allow dialysis

Rarely, the needles in your arm may come out, or a tube may disconnect from your hemodialysis. In these situations, the machine will alert you or your provider. The machine then shuts off to protect you from blood loss until someone fixes the problem.

What are the side effects?

Hemodialysis side effects may include:

• Low blood pressure
• Nausea and vomiting
• Dizziness
• Fainting
• Chest pain
• Back pain
• Headaches
• Itchy skin
• Muscle cramps
• Restless legs syndrome

How long can you live on hemodialysis?

If you’re on hemodialysis, the average life expectancy is five to 10 years. But some people have lived up to 30 years on hemodialysis. Your provider will give you a better idea of what to expect according to your situation.

Will I need to continue treatments for the rest of my life?

Hemodialysis can’t cure late-stage CKD or kidney failure. Unless you get a kidney transplant, you’ll need hemodialysis for the rest of your life.

But sometimes, a sudden kidney failure only needs temporary dialysis. Your healthcare provider will stop dialysis once your kidneys start working again.

What is the recovery time?

Most people start to feel better a few weeks after starting hemodialysis.

Reach out to your healthcare provider if you feel sick or tired after your session. They can prescribe medications or make adjustments to help you feel better.

What happens if I refuse it?

If you choose not to start or decide to stop hemodialysis, you’ll develop uremia. Your kidneys will eventually fail. Over time, kidney failure is fatal. You may survive a few days or weeks without hemodialysis if you have kidney failure.

Refusing or stopping hemodialysis is a personal choice. Before making a decision, you should share your feelings with your provider, family and friends.

Is there anything I can do to make this treatment easier on me?

Managing CKD or kidney failure can be frustrating. The following tips may make hemodialysis easier:

• Wear warm clothes: Many people feel chilly as the hemodialysis machine withdraws blood from the body. Sitting still for several hours can also cause you to feel cold. It’s a good idea to wear socks, pants, a hat or a sweatshirt to help stay warm. Make sure your top has loose sleeves that you can easily roll up to access your fistula or graft.
• Bring something to do: Hemodialysis sessions can be boring. It’s a good idea to bring something to keep yourself busy or entertained. This may include a laptop, smartphone, book, video game system, playing cards, or paper and a pencil.
• Find a support group: Talking to people who understand what you’re going through can help reduce feelings of stress, anxiety, depression and isolation.
• Work with a renal dietitian: Working with a renal dietitian can help you feel better between sessions and reduce any side effects.

When should I call my healthcare provider?

Contact your healthcare provider if you experience:

• Signs of low blood pressure, including dizziness, fainting or dehydration
• Nausea and vomiting
• Signs of infection, including warmness or discoloration around your fistula or graft, a fever or chills
• Severe pain in your abdomen
• A bulge in your abdomen (hernia)

What is the difference between hemodialysis and peritoneal dialysis?

During hemodialysis, your blood leaves your body and enters a machine that filters out waste products and extra fluid. Once the machine filters your blood, it goes back into your body.

During peritoneal dialysis, your provider attaches a catheter to your abdominal lining (peritoneal membrane). A bag with a dialysis solution then attaches to a catheter. The solutions flows from the bag into your peritoneal cavity. It absorbs waste products and extra fluid. About 60 to 90 minutes later, you drain the solution with the waste products and fluid into a clean, empty bag.