Which dialysis forms are there?
In Germany, 86.1% is hemodialysis (HD). In this case, an "artificial kidney" (= hemodialyzer) is connected directly to the bloodstream, which, although no optical similarity with the right kidneys, but can imitate their function within certain limits. However, their detoxification capacity is no more than 10-15% of healthy kidneys.
The hemodialyzer consists of a system of several plastic membranes, on which the anticoagulated blood is passed by means of a pump. On the other side there is a salt solution, in which the waste products pass through the concentration difference. In addition, water is pressed off ("ultrafiltration"). A machine monitors the exact sequence, the functions, temperature, blood pressure and other parameters. The procedure lasts 3-5 hours and requires about 120 liters of water.
What is a shunt?
As the toxins gradually re-accumulate in the blood, the treatment must be done about 3 times a week. Since this regularly requires access to the blood system of the patient, this gets a so-called shunt - a permanent connection between an artery and vein, usually on the forearm, whereby the vein expands greatly and therefore can be well punctured.
The treatment is usually carried out in special dialysis centers, but is also possible as home dialysis. Relatively common side effects of HD are circulatory disorders with hypotension and nausea, muscle spasms and cardiac arrhythmias, as well as infections and occlusions of the shunt.
In this form, the waste does not pass the membrane passively but is actively pressed through it. The removed fluid is replaced with an infusion solution. HF is only used in 0.1% to 1.3% of cases.
As the name suggests, this process is a combination of the above two methods. Depending on the federal state, between 5 and 24% is used.
Peritoneal dialysis (PD)
This procedure makes use of the semipermeable properties of the peritoneum and the vessel walls. The patient is implanted with a permanently lying plastic catheter through which the sterile rinsing fluid is introduced into the abdominal cavity 4 to 6 times a day, left there for 5-8 hours and then drained off again. The toxins from the blood migrate through the peritoneum and can be removed.
The procedure can be carried out in various modifications and with additional equipment by the patient himself. This has the advantage of independence and flexibility, a more uniform concentration of the toxins in the blood and less strict dietary requirements. This makes the PD especially suitable for children. Disadvantage is that the danger of peritonitis is increased. By adding sugar in the rinsing liquid, the excess water is removed from the body, but there is a risk of metabolic disorders. In Germany, PD is used in about 1-7% of patients.