Dialysis in chronic kidney disease

Photo of a man during dialysis (PantherMedia / SimpleFoto)

Dialysis makes it possible to continue living with end-stage kidney disease for many years or even decades. There are different types of dialysis. Dialysis at a dialysis center is a good option for many people. Others may prefer a method they can use at home.

A kidney transplant is often the best option for people who have end-stage kidney disease, but it's not always possible. In that case, and while waiting for a donor kidney, it’s necessary to have renal (kidney) replacement therapy with dialysis.

There are two main types of dialysis, known as hemodialysis and peritoneal dialysis. The most suitable type will depend on medical factors. But because the ways the different types are used in everyday life are so different, personal preferences play a major role in the decision too. So it’s a good idea to learn about the different types of dialysis and talk with your family and doctor to decide which one is the most suitable for you.

Thanks to dialysis, it’s possible to live with the disease for many years. How well it works will mainly depend on whether you have any other medical conditions and – if so – what kind, how well the dialysis is prepared, and how successfully you can handle the dialysis, medication and dietary recommendations.

What does hemodialysis offer?

Hemodialysis is the most commonly used type of dialysis in Germany. In this method, blood is transported out of the body through tubes and cleaned in a machine using dialysis fluid. The dialysis is typically carried out three times per week. Each session lasts about four to five hours.

Hemodialysis is usually done at a dialysis center, but it’s also possible to do it at home (home hemodialysis). The costs of home dialysis are covered by statutory health insurers in Germany, just as they are for in-center dialysis. Medical staff at the center make sure that everything runs smoothly. This gives most people a feeling of safety and is an advantage for those who don’t feel comfortable with home hemodialysis.

Home hemodialysis allows for more independence and flexibility, though. You aren’t limited by the opening hours of the dialysis center, and it saves you the travel time to get there. But home hemodialysis isn’t possible without having training at a dialysis center and the support of one family member who has also been trained. There also needs to be enough space at home for the dialysis machine and the necessary equipment. It’s not clear whether there are differences in life expectancy between people who have in-center hemodialysis and those who have home hemodialysis. There is a lack of suitable research in this area.

If you are traveling away from your usual center, you can get “holiday dialysis” at a different center. Traveling to more distant countries is also possible: You will usually just need to make arrangements for dialysis at your travel destination in advance. If people who have statutory health insurance in Germany receive dialysis in other countries, the costs are covered up to the amount that it would cost in Germany.

What are the disadvantages of hemodialysis?

Some people feel like they are “dependent” on the dialysis machine. The long treatment times and the time it takes to get there and back can also be a burden and make it more difficult to see friends and family. The scheduled dialysis appointments at the center are usually on weekdays and during the day – which can be a problem for people who would still like to work. So most larger centers offer evening hours as well.

Hemodialysis only works with the right type of passageway to access the bloodstream. Because superficial veins don’t suit this purpose, a small operation is needed several weeks or months before hemodialysis can be started. The procedure involves connecting a vein and an artery in the forearm, if possible. This “short-circuit” of the blood's circulation (called an arteriovenous fistula or a shunt) allows a slightly larger blood vessel to form, into which the dialysis cannulas can be inserted.

The procedure needs to be done some time before dialysis is started because it takes a while for the fistula to fully develop. An arteriovenous fistula is the best passageway for hemodialysis because it is associated with the fewest complications. It can also be distressing, though: Some people feel constantly reminded of their condition and their dependency on dialysis. Sometimes, that's enough of a reason to opt for peritoneal dialysis instead. This type of passageway is also the cause of the typical complications of hemodialysis: The new blood vessel may become inflamed, for example, or be blocked by a blood clot. If it’s not possible to have an arteriovenous fistula, hemodialysis can also be done using a “neck line.” This is where a catheter is inserted into a large vein in your neck that is close to the heart.

Hemodialysis usually doesn’t lead to any complications. During the time that the person is connected to the dialysis machine, problems like a drop in blood pressure or seizures may occur – but that is rare. Blood clotting must be suppressed with medication during dialysis too.

What does peritoneal dialysis offer?

In peritoneal dialysis, the blood isn't cleaned outside the body but on the inside, in the abdominal cavity (the hollow space surrounding the organs in the abdomen), with the help of dialysis fluid. Patients are given a special abdominal catheter: About two liters of the dialysis fluid are transported into the abdominal cavity through this catheter. After some time, this fluid is then removed and replaced with new dialysis fluid. This type of dialysis can also be done at home on your own.

Two basic methods are used in peritoneal dialysis. The standard method is called continuous ambulatory peritoneal dialysis (CAPD). In this method, the fluid is manually exchanged three to four times per day, and no machine is needed. But you do need to get extensive training from medical professionals to learn how to handle the catheter hygienically. In CAPD, the abdomen is always “filled” with dialysis fluid.

If you don’t want to exchange the fluid during the day or if you don't have the opportunity – because you’re at work, for example – you can use automated peritoneal dialysis (APD) every night instead. Here, the catheter is connected to a device called a cycler that regularly exchanges the dialysis fluid.

Which of the two methods is more suitable for peritoneal dialysis will also depend on the specific properties of the peritoneum (the lining of the abdominal cavity), though: So CAPD may be more suitable for some people, but APD might be a better option for others.

Like in hemodialysis, there are certain recommendations for eating and drinking in peritoneal dialysis too. But they are not quite as strict as the ones for hemodialysis.

If you start finding it hard to manage with peritoneal dialysis, you can switch to hemodialysis (or vice versa).

What are the disadvantages of peritoneal dialysis?

As in hemodialysis, surgery is needed here too, to implant a permanent catheter into the abdominal cavity. The most common complications of peritoneal dialysis have to do with the catheter:

  • If bacteria enter the abdomen, they can cause inflammation of the peritoneum (peritonitis).
  • The tip of the tube may result in painful irritation of the mucous membranes lining the inside of the abdomen.
  • If the opening of the tube sticks together or the tube gets a kink in it, dialysis will become more difficult or may no longer be possible.
  • The opening in the abdominal wall where the tube goes in may become infected.

Most dialysis fluids contain sugar to help remove excess fluid from the body. Experts believe that the sugar may be released into the bloodstream over time and cause people to become overweight. In people with diabetes, blood-sugar-lowering treatments may then need to be adjusted accordingly.

Research summaries

What is hemofiltration?

In hemofiltration, blood is transported through tubes into a machine and cleaned there. No dialysis fluid is needed: Instead, pressure is applied to remove water and waste products from the blood. If this method is combined with hemodialysis, it is called hemodiafiltration. In Germany, both of these methods are only very rarely used to treat people with chronic kidney disease. There are also not enough high-quality studies showing that they are better than conventional dialysis.

Can you decide not to have dialysis?

Aside from a kidney transplant, there is no alternative to dialysis that allows you to live for a longer time if your kidneys aren’t working well enough. Some people with kidney failure still opt to not have dialysis, though – for example, because they are very old and have other medical conditions. Making this decision means letting your life come to an end. It is often difficult for friends and family to accept – so it's important to discuss it with them first. Support from family and friends also becomes especially important in the weeks and months to come.

Anyone who decides not to have dialysis can continue treatment with medication and may live for another few weeks or months despite the kidney failure. Palliative care is then important towards the end of life. It can reduce pain and other symptoms, and aims to maintain quality of life as much as possible. That may involve things like being allowed to eat and drink a greater variety of things, or whatever you feel like.