Dialysis

Dialysis is an apparatus-based method for the treatment of certain diseases or symptoms in which the body’s kidneys are unable to perform their work adequately or at all, or in which the patient no longer has a kidney. In principle, in all variants of dialysis, all the patient’s blood is passed through a kind of filter, freed from harmful substances and excess water and then returned to the body in a purified state – hence the popular synonym for dialysis: blood washing. In most cases, it is therefore a renal replacement therapy due to terminal kidney failure.

The first dialysis of the diseased person in accordance with today’s principle was carried out in Gießen in 1924. The technology became available to a wider public from around 1945 onwards and has been subject to constant development with a growing number of applications. Today, dialysis is the mainstay of renal replacement therapy, so that in 2010 there were about 70,000 patients in Germany requiring permanent dialysis, and the number is rising.

Functions of the kidney

The kidney, of which every human being usually has two, is one of the most important organs of the body, without which the human being would not be viable. Not only does it regulate the body’s water balance through urine excretion. It also filters harmful substances that the body cannot break down from the blood and is crucial in maintaining the electrolyte composition of the blood, i.e. the dissolved salts and ions.

In addition, the kidneys produce hormones such as Epo (erythropoietin), which is important for blood production and is probably known to most people from cycling, and regulate the pH. The pH value is a measure of the ratio of chemical acids and bases in the blood, which must be kept constant within narrow limits. The kidney also plays a decisive role in adjusting blood pressure.

This shows the importance of this organ and thus of dialysis as an important therapeutic option. When using dialysis therapy, a distinction must be made between acute complaints and chronic diseases. In the area of acute events, dialysis is suitable for the rapid restoration of vital functions.

The main areas of application here are acute, sudden kidney failure or a high-grade overhydration that cannot be treated with medication, as well as acute poisoning. However, dialysis has the greatest relevance as the most important instrument of renal replacement therapy. It is used whenever the kidneys themselves are no longer able to perform the tasks assigned to them, or can no longer perform them adequately.

On the one hand, this occurs when the kidneys are no longer available, e.g. as part of a tumor therapy in which both kidneys had to be removed. On the other hand, however, the vast majority of dialysis patients have chronic kidney failure, i.e. kidneys that work too poorly. In both cases, the above-mentioned tasks are performed by the dialysis machine. In rare cases, dialysis is also used in cases of liver disease.