Currently, every tenth Pole has a condition related to the excretory system, mostly kidneys. Every year, 6-10% of young people suffer from an infection of the urinary tract, while in the group of people over the age of 50 it afflicts 20% of the population. One of the most frequent and serious diseases of today’s civilisation – diabetes – pertains to over 2 million people nationwide. It is the first and the most common determinant behind the development of end-stage renal failure, which makes it necessary to commence treatment.
Chronic renal failure is a complex syndrome, usually characterised by slow but irreversible and progressing deterioration in the kidney function. At the heart of this disease lies a system of conditions that destroys renal parenchyma, leading to impairment of both the excretory and the secretory function of the organ (impaired secretion of the erythropoietin hormone). As a result, kidneys are unable to remove harmful substances toxic to man and excess water from the body. These compounds accumulate in the patient’s body, which causes disease symptoms and damages other internal systems, such as: the gastrointestinal tract, the immune system, the cardiovascular system and the skeletal system.
Once kidneys are unable to remove excess fluids, mineral components or metabolites from the blood, produce hormones and stimulate formation of erythrocytes, contemporary medicine uses a renal replacement therapy known as dialysis. It is one of the most common methods of treating chronic renal failure. The dialysis system was introduced in 1960s and it became a commonly used procedure all over the world.
For dialysis to be usable and – what’s most important – effective, a way of taking blood from the patient’s body, filtering it through a dialyser and reintroducing thus purified blood to the patient’s body had to be developed. Since such a process had to be repeated many times, continuous access to the patient’s blood vessels was required. This problem was solved by arteriovenous fistula. It is the most common and the safest way of accessing human blood circulation system, which makes haemodialysis a legitimate and effective procedure. Other ways of achieving such access, used depending on the patient’s condition, are: arteriovenous graft and central venous catheter.
A dialysis fistula is created via an incision made on a wrist, an arm or a leg to join an artery and a vain into one structure. Under normal conditions these blood vessels never occur as a combined vessel because their functions in human body largely differ. The procedure lasts about an hour and it is performed with local anaesthesia. The combining of the vessels causes faster and more powerful blood flow. Such an arteriovenous connection can be congenital or formed as a result of an injury. Fistulas can occur in all areas of human body but they are most frequent on lower extremities and between encephalic vessels.
Another way of treating chronic renal failure is peritoneal dialysis. It permits removing the accumulated fluids and – in severe cases – uraemic toxins from the patient’s body. The dialysis progresses in the abdominal cavity, which is the site of exchange between the blood filling the vessels of the patient’s peritoneal membrane or the natural membrane surrounding abdominal organs and the dialysis fluid situated in the peritoneal cavity.
