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| Artificial Kidney |
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| The haemodialyzer or artificial kidney is a machine used to filter the blood of a person whose kidneys are damaged. The process is called haemodialysis. |
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| Haemodialysis is defined as the seperation of small molecules from large molecules in a solution by interposing a semipermeable membrane between the solution and water. |
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| It works on the principle of dialysis, which is the diffusion of small solute molecules through a semipermeable membrane. |
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| The haemodialyzer consists of a cellophane tube suspended in a salt - water solution of the same composition as the normal blood plasma, but without any urea present in it. |
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| Blood of the patient is pumped from one of the arteries into the cellophane tube after cooling it to 0oC and mixing it with an anticoagulant heparin. The pones of the cellophane tube allow urea, uric acid, creatinine and excess salts to diffuse from the blood into the surrounding solution. |
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| The blood which is now purified, is warmed to body temperature, mixed with an anti heparin to restore its normal clotting power and is checked to ensure that it is isotonic to the patients blood. It is then pumped into a vein of the patient. Plasma proteins remain in the blood as the pones of the cellophane are too small to permit the passage of their large molecules. |
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| Flow of blood through an artificial kidney for haemodialysis |
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| The use of dialysis creates a lot of discomfort and the added risk of formation of clots. It may cause fever, cardio vascular problems and haemorrhage. |
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| So an effective alternative treatment would be to have a kidney transplant. |
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