Question

What is dialysis and how does this process take place?
[5 Marks]

Answer 1

The process of removing metabolic waste and excess fluids from the body artificially is called dialysis. This process is done when an individual’s kidney fails to perform its functions.
[2 Marks]

The following are the steps involved in dialysis process:

• The arterial blood is passed through the dialysis unit.
• While the blood is being passed through the machine, heparin is utilised as an anticoagulant.
• The dialysis unit receives a fluid called dialysis fluid which is composed of water, electrolytes and minerals.
• A semipermeable barrier in the unit prevents blood cells and proteins from diffusing into the dialysis fluid.
• The concentration gradient allows urea, phosphate, creatinine, and other undesirable chemicals from the blood to flow into the dialysis fluid.
• The dialysis fluid releases the body's vital chemicals into the bloodstream.
• The purified blood is being pumped back to the body through a vein and the used dialysis fluid is disposed off. [3 Marks]