dialysis

Dr. med. Philipp Nicol is a freelance writer for the medical editorial team.

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Dialysis is a medical procedure that removes harmful substances from the blood. It is also known as blood washing. Dialysis is used primarily for acute or chronic kidney problems. Read everything about dialysis, when to perform it and what the risks are here.

What is dialysis?

Dialysis is an artificial blood wash that removes toxic substances from the blood.

The body produces many toxic metabolic products every day, which are normally excreted in the urine through the kidneys. These so-called “urinary substances” include, for example, urea, uric acid, creatinine and many more.

If the kidneys are unable to adequately excrete these substances due to acute or chronic damage (acute or chronic kidney failure), they accumulate in the body, which can become life-threatening within a few days.

The first human dialysis was carried out in Gießen in 1924 - since then it has saved the lives of millions of people. Around 70,000 people are currently dialyzed on a permanent basis in Germany.

Dialysis can also be used for certain types of poisoning to remove the toxin from the body.

There are basically three dialysis methods:

• Hemodialysis
• Peritoneal dialysis
• Hemofiltration

The principle of all three processes is similar: blood is continuously taken from the body and filtered through a membrane (dialyzer). A rinsing liquid (dialysate) is sometimes used to wash out the substances in the blood. The purified blood is then returned to the body.

Further information: hemodialysis
When to perform hemodialysis and what to watch out for, read the article on hemodialysis.

Further information: peritoneal dialysis
When to perform peritoneal dialysis and what to watch out for, read the article on peritoneal dialysis.

The third method is hemoperfusion. It is used to cleanse the blood in cases of poisoning. The blood is fed into containers with activated charcoal, which removes the poison from the blood and binds it (adsorption).

When do you have dialysis?

Dialysis can be used acutely and only for a short time or as a long-term treatment.

Acute dialysis

Acute dialysis must be used in the following situations:

• Acute kidney failure: Signs of this are, for example, rising potassium levels, signs of overhydration (hypervolaemia) or symptoms of poisoning due to substances that are phased out in the urine (uremia)
• Poisoning: In the event of poisoning with dialyzable substances (for example the antidepressant lithium or methanol), dialysis can save lives

Chronic dialysis

In the case of advanced, chronic renal impairment (chronic renal insufficiency), dialysis is used as a long-term, usually lifelong treatment (long-term dialysis). Dialysis must then take place regularly, for example every other day.

The following symptoms, among others, may indicate a deterioration in kidney function:

• severely increased blood pressure
• Changes in blood salts (electrolytes)
• Changes in blood pH
• glomerular filtration rate (GFR) as a measure of kidney function below 10 to 15 milliliters per minute

What do you do with dialysis?

For dialysis, large amounts of blood are drawn in a short time and then returned to the body in a clean state. But the blood vessels are either difficult to access (arteries) or have too little pressure (veins) and are therefore not suitable for dialysis. For this reason, a special vascular access is surgically created during long-term dialysis - a so-called dialysis shunt.

Long-term dialysis vascular access (shunt)

For long-term dialysis, an operative connection is created between the artery and the vein (AV shunt) - for example by inserting a small plastic tube (interposal). For dialysis, the graft is pierced with a needle. In principle, a dialysis shunt can be used in many places, but the less used forearm is preferred (e.g. the left arm for right-handed people).

This vascular access is permanent and avoids repeated puncturing of the vessels with the associated risks such as infections or injuries.

Vascular access for acute dialysis

Large cannulas (Shaldon catheters) are used for short-term or acute dialysis. This dialysis catheter can be used in the inguinal, collarbone or jugular vein.

Anticoagulation

During dialysis, the blood comes into contact with the components of the dialysis machine. These are usually made of plastic and activate blood coagulation (one also speaks of thrombogenic material). For this reason, blood coagulation (anticoagulation) must be inhibited for the duration of the dialysis treatment, for example by administering heparin.

Another possibility is the so-called regional anticoagulation: citrate is added to the dialysis machine, which binds the calcium in the blood and necessary for the coagulation process and thus inhibits blood clotting in the dialysis machine. At the end of the blood wash, the administration of calcium removes the citrate effect again.

Dialysis procedure

Depending on the dialysis method, dialysis can be carried out on an outpatient basis in a special dialysis center or at home (home dialysis).

Dialysis in the hospital or doctor's office
Hemodialysis and hemofiltration are performed in the hospital. With long-term dialysis, the blood is washed three times a week for four to five hours under supervision. A shunt is required for this type of dialysis.

Dialysis at home
Peritoneal dialysis can be done at home. The advantage of this method for the patient is the great independence. You do not have to go to the hospital regularly, but can do the dialysis independently and on your own responsibility - for example at night.

What are the risks of dialysis?

Dialysis is a standard procedure in kidney replacement therapy. Nevertheless, it carries certain risks. The most common dialysis side effects include:

Drop in blood pressure

Dialysis is a significant burden on the body. A common reaction is a drop in blood pressure. The drop in blood pressure can be counteracted by lowering the filtration rate (you should not dialyze more than 600 milliliters of blood per hour). It also helps to lower the temperature of the blood in the dialysis machine a little. So the body temperature remains rather low, which in turn stabilizes the blood pressure.

Muscle spasms

Dialysis removes minerals from the body - this promotes muscle cramps. A massage usually helps. The doctor may also give you a low-dose, muscle-relaxing sedative (such as diazepam).

headache

Headaches are also a common side effect. Classic pain relievers with active ingredients such as paracetamol provide a remedy here.

Nausea and vomiting

A drop in blood pressure can cause vomiting. Nausea is common after long dialysis sessions. It usually helps to treat the drop in blood pressure; if necessary, MCP-containing agents can also be administered to prevent nausea and vomiting.

Other side effects can include itching, fever, chills, irregular heartbeat, and chest or back pain.

The so-called dysequilibrium syndrome is rather rare: symptoms such as headaches, impaired consciousness or epileptic seizures occur. It is believed that dialysis removes substances from the body that lead to the transfer of fluid from the vessels into the tissue. The tissue swells, which in extreme cases can lead to life-threatening brain edema.

Vascular Access Complications

Various complications can occur with an AV shunt:

• Infection of the shunt
• Aneurysm (wall widening)
• decreased blood flow to the body area behind the shunt
• Closures

Dialysis - Life Expectancy

Despite medical progress, dialysis patients have a shorter life expectancy than healthy people, especially if they have additional comorbidities such as diabetes mellitus. The cause is the underlying disease (kidney failure), which can be associated with serious complications such as heart attack or stroke.

What should I watch out for after dialysis?

Dialysis treatment means a significant interference in everyday life: the intensive treatment has an impact on social and professional life. In order to cope with this and avoid additional stress, the support of family, friends and colleagues is particularly important.

Dialysis Diet

You can influence the proportion of urinary substances through your diet. At the same time, dialysis removes important substances from the body, which can lead to weight loss in the long term. You should therefore take the applicable recommendations into account and, if necessary, seek support from a dietician who can put together an individual menu for you.

Further information: Dialysis: Nutrition
How to eat properly as a dialysis patient and how you have to pay attention to it can be found in the article Dialysis: Nutrition.

Dialysis vacation

Above all, the loss of mobility and independence is a limitation due to dialysis. Going on vacation is still possible. Today dialysis patients can travel anywhere in Germany and in most countries of the world. A place for hemodialysis can also be found within Germany at short notice. When traveling abroad, you should plan more time for organization. It is advisable not to go on vacation as a new dialysis patient, as the body needs time to get used to the treatment.

Dialysis cruises are offered especially for dialysis patients: this is a completely normal cruise with the option of dialysis under medical supervision.

What should you consider before starting your trip?
Hemodialysis patients around the world can take advantage of what is known as guest dialysis. Addresses for this holiday dialysis can be found in self-help groups, specialized travel agencies or in the advertisements of specialist magazines. Dialysis guides, which are available in most dialysis practices, provide additional information. You can book a dialysis place before you start your journey. To do this, the guest dialysis center needs information on the desired dialysis days and times. Travel agencies that specialize in holiday dialysis take care of the planning and coordination.

In general, dialysis patients should not travel to areas with poor hygienic conditions. There is a significantly higher risk of infection here. It is also important to clarify the cost of dialysis abroad with your health insurance company before the start of your vacation.

What kind of support do doctors offer?
Before you decide to have hemodialysis while on vacation abroad, you should definitely discuss this with your doctor. He will advise you whether the selected holiday region is an option and whether your general state of health allows you to travel. The doctor compiles all data relevant for hemodialysis such as dry weight, dialysis time, laboratory values ​​or medication to prepare for the guest dialysis.

Before you go on vacation, you should send this data to the guest dialysis practice. Depending on the country of vacation or the guest dialysis practice, you will need to take certain medication with you. Your doctor should write a prescription in good time so that all medication is available when you go on holiday. Your doctor will also advise you whether it makes sense to become a member of an organization for dialysis patients that may organize a return campaign. This could be necessary in the event of an upcoming transplant or an unexpected deterioration in health. Patients who are on dialysis via the peritoneum (peritoneal dialysis) should also consult their doctor before traveling.

Nowadays, dialysis is a standard procedure that, with the right care, enables an almost normal life.

Tags:  prevention Diseases menshealth