Acute kidney injury

Question 1

acute kidney injury

Answer 1

deterioration in kidney function within a few hours or days

Question 2

acute kidney failure

Answer 2

when renal injury progresses to the point where kidney stops working entirely

Question 3

Pre renal kidney failure

Answer 3

1. reduction of blood flow to the kidneys leading to underperfusion
2. Reduced blood supply -> reduced gfr
3. Reduces urine output (oliguria) - accumulation of water and body fluids
4. If blood flow falls below 25% of normal - kidney injury cannot be restored
5. Cells become hypoxic, necrosis, further reduction in blood flow
6. Can progress to intrarenal AKI

Question 4

Causes of pre renal kidney injury

Answer 4

Hypovolemia - Diarrohea, haemorrhage, vomiting, reduced CO, Cardiac Failure
MI
Sepsis - systemic vasodilation

Question 5

Intrinsic renal failure

Answer 5

Injury within the kidney itself

Question 6

Causes of intrinsic renal failure

Answer 6

1. Conditions which damage the glomerular capillaries
   - Acute glomerularnephritis
   autoimmune reaction which damages the glomerulus
   - Malignant hypertension
2. Main cause is Acute Tubular Necrosis
   - Severe ischaemia - dead cells plug up nephrons so there is no urine output
   - toxins or medication
   3, Damage renal interstitium
   - Acute interstitial nephritis - hypersensitivity reaction, causes inflammation and damage to tubules.

Question 7

Post renal acute kidney injury

Answer 7

obstruction of the urinary tract leading to intratubular pressure and fall in GFR

Question 8

Causes of post renal kidney injury

Answer 8

• Obstruction of urinary tract
• Prostatic hypertrophy
• Stones
• Tumors ( prostate/cervical )

Question 9

Clinical manifestations of acute kidney injury

Answer 9

• Oedema and hypertension - retention of water and waste products
• Hyperkalemia - retention of K+ ions
• Retention of H+ - metabolic acidosis -> high resp rate