When the kidneys no longer manage to perform their function of excreting toxins and water, their duties must be taken over elsewhere. Various methods of blood washing are available, as well as transplanting foreign kidneys. In Germany, nearly 80,000 people are affected.
When are kidney replacement procedures used?
In principle, the answer is simple: whenever kidney function is so poor that the affected person would develop urinary toxicity without therapy. The most common cause is chronic renal failure, also known as chronic renal insufficiency in the medical jargon. This is based on many possible triggers – first and foremost diabetes and high blood pressure.
In the case of chronic renal failure, either blood purification (dialysis) must be carried out for the rest of the patient’s life or the patient receives a new kidney (kidney transplant). Renal replacement therapy is also used for acute kidney failure. Dialysis is used to bridge the time until the causal underlying disease is overcome and kidney function is restored. In addition, blood washing is also used in cases of poisoning to remove harmful substances from the body as quickly as possible.
How does dialysis work?
The principle of all forms of dialysis is the same: particles and water pass through differences in concentration and/or actively applied pressure to the other side of a membrane, where there is an exchange fluid (dialysate). In this way, urinary waste products and excess water can be removed from the blood. The membrane can be outside (extracorporeal) or inside (intracorporeal) the body. A
hemodialysis, hemofiltration, and hemodiafiltration, which use an artificial membrane, are based on the first principle; peritoneal dialysis, which uses the peritoneum as the membrane, is based on the second.