What is hemodialysis?
In hemodialysis, blood is sent outside the body through an artificial membrane to remove harmful substances. This membrane functions like a filter, i.e. it is only permeable to a part of the substances.
Conversely, the patient’s blood can be enriched with appropriate substances in the course of hemodialysis through a specific composition of the dialysate. Harmful substances are thus removed from the blood and desirable substances are added back.
Dialysis shunt
Dialysis patients therefore need a safe and stable vascular access: they are given a so-called dialysis shunt. Vascular surgeons usually sew together an artery and a vein in the forearm (Cimino shunt). The procedure usually takes place under local anesthesia (regional anesthesia).
Because blood flows at a higher pressure in arteries than in veins, the blood flows into the vein via the dialysis shunt at an unusually high pressure. To accommodate this, the vein expands over time and develops a thicker wall. It can then be repeatedly pierced for dialysis. Until the wall of the vein reaches a sufficient thickness, dialysis is performed through a catheter. It is usually placed on the patient’s neck or chest.
When do you perform hemodialysis?
Hemodialysis is used:
- for a few days in acute kidney failure or in cases of poisoning.
- as a permanent therapy for chronic kidney failure (chronic renal insufficiency) in advanced stages.
What do you do during hemodialysis?
Dialysis patients usually have to come to a special treatment center three times a week for four to eight hours each time. Hemodialysis is therefore time-consuming – with all the restrictions this imposes on a job and normal everyday life.
Hemodialysis as home dialysis
Hemodialysis as home dialysis requires a great deal of personal responsibility on the part of the patient, but offers him greater time flexibility than hemodialysis in a dialysis center. In addition, treatment complications (such as problems with the dialysis shunt) occur much less frequently with home dialysis.
What are the risks of hemodialysis?
Phosphate can accumulate in the body due to kidney weakness. The result can be hyperparathyroidism, followed by bone damage and arteriosclerosis. Dialysis patients consequently take tablets at every meal that bind the phosphate. If the calcium level in the blood permits, those affected also receive vitamin D, as this is important for the absorption of calcium into the bones.
What do I have to consider during hemodialysis?
Hemodialysis puts a strain on the body and restricts the patient in terms of timing and nutrition. However, it is vital if the kidneys fail. Dialysis can often bridge the long wait for a new kidney (kidney transplant).
However, such complications can be significantly reduced or delayed by optimal hemodialysis treatment. That is why doctors also pay attention to other diseases such as high blood pressure, dyslipidemia and anemia (renal anemia), which can develop as a result of chronic kidney failure.
