Explain the concept and mechanism of dialysis.

Asked by manya.bhardwaj.01 | 19th Jun, 2017, 04:09: PM

Expert Answer:

Concept of Dialysis:

  • If one kidney is damaged or removed, then the other kidney alone can fulfil excretory needs. 
  • However, the failure of both the kidneys allows urea and other wastes to accumulate in the blood.
  • Such a patient undergoes dialysis.
  • In dialysis, an artificial kidney is used.

Mechanism of Dialysis:

  • The artificial kidney contains tubes made of cellophane with a semi-permeable lining.
  • These tubes are suspended in a tank filled with a dialysing solution.
  • This fluid contains water and glucose in concentrations similar to those in blood.
  • The patient’s blood is led from the radial artery and cooled at 0°C.
  • Then anticoagulant heparin is added to the blood.
  • Blood is then passed through semi-permeable coiled cellophane tubes.
  • The tubes allow small molecules such as urea, creatinine, uric acid to pass out.
  • Also metabolic wastes are filtered out in the surrounding solution.
  • But the macromolecules such as proteins are retained in the blood.
  • Purified blood is then mixed with antiheparin and warmed to the body temperature.
  • The purified blood is returned through a vein in the same arm.
  • The function of dialysis is similar to the function of the kidney, but the only difference is there is no reabsorption during dialysis.

Answered by Sheetal Kolte | 19th Jun, 2017, 07:06: PM