Discuss the Management of Kidney Failure by Dialysis and Transplant
Most humans are born with two bean-shaped kidneys (approximately 11cm long and 6cm wide) located in front of the twelfth ribs at the back of the abdominal cavity. Oxygenated blood and nutrients are supplied to the kidneys by the renal artery and the renal vein carries away filtered blood to the heart.
Kidneys play a crucial role in homeostasis, working as vital filtration and purification organs. They filter poisonous urea and other waste products from the bloodstream so that they can be eliminated by excretion from the body in urine. The production of urine containing variable amounts of water and solute concentrations allows the kidneys to control the water and ion content of the body; osmoregulation. They produce the hormone, erythropoietin, which stimulates erythrocyte production in the bone marrow.
Complications of diabetes, uncontrolled hypertension, inflammation affecting kidney tissue and inherited diseases, such as polycystic kidney disease, are the main causes of kidney failure. Toxins, including urea and other nitrogenous wastes are not filtered from the blood and amass in the tissues. The kidneys are rendered incapable of maintaining the composition of body fluids. Currently 35,000 UK residents receive treatment for kidney failure. Patients are often anaemic, feel ‘run down’ and suffer with cramps, loss of appetite, itching or vomiting. Kidney failure, once inevitably fatal, can be treated by three options: haemodialysis, peritoneal dialysis and kidney transplant.
Haemodialysis, the most common treatment for kidney failure, uses a filter known as a dialyser as an artificial kidney. The patient’s arterial blood, about 200cm3 outside the body at any one time, is usually pumped from a shunt from a vein in the forearm through the dialyser where molecules are exchanged between the dialysate and the blood. A net movement of urea, water, glucose and salts such as sodium and potassium...