5.2.9 Kidney Failure

Question 1

What can cause kidney failure?

Answer 1

• Blood loss (accident)
• High BP
• Diabetes
• Overuse of drugs
• Infections

Question 2

What happens if the kidney fails?

Answer 2

• Urea, salts and toxins aren’t excreted
• Less blood filtered by glomerulus so GFR decreases

Electrolyte balance in blood is disrupted
- Excess K+ causes cramps and potentially cardiac arrest
- Excess Na+ causes muscle spasms and higher BP

Question 3

What are the forms of treatment for kidney failure

Answer 3

• Renal Dialysis
• Kidney Transplant

Question 4

Types of renal Dialysis

Answer 4

• Haemodialysis
• Peritoneal Dialysis

Question 5

What is haemodialysis?

Answer 5

• Regular treatment (hospital or in home)
• Partially permeable dialysis membrane separates patients blood from dialysis fluid
• Blood is passed through a tube surrounded by dialysis fluid
• Dialysis fluid contains substances needed in blood at the right concentrations (equal conc of glucose and salts on both sides, no urea)
• Dialysis fluid refreshed to maintain concentration gradient
• Patient’s blood and dialysis fluid flows in opposite directions, (concentration gradient)

Question 6

Kidney Transplant

Answer 6

• Medication must be taken to prevent patient’s immune system from rejecting kidney
• Better long term solution
• More freedom (not tied to dialysis machine for hours a day)
• Diets less restricted
• Less expensive to run machine
• Permanent

However :
- Kidney does not have the same antigens on cell surface so an immune response occurs to the kidney
- Immunosuppressant drugs need to be taken for life
- Not enough donors