Wk 10: Biochemistry: Renal (AKI)

Question 1

Define acute kidney injury (stage 1)

Answer 1

• SCrinc ≥ 26μmol/L w/in 48hrs
• SCr inc ≥ 1.5x from reference, w/in a week
• Urine output <0.5ml/kg/hr for >6hrs

Question 2

What is stage 2 AKI?

Answer 2

• SCr inc ≥ 2 - 2.9x from reference
• Urine output <0.5ml/kg/hr for >12hrs

Question 3

What is stage 3 AKI?

Answer 3

• SCr inc ≥ 3x from reference

OR

• On Renal replacement therapy
• Urine output <0.3ml/kg/hr for >24hrs

OR

• Anauria 12hrs

Question 4

When would you refer a patient with AKI?

Answer 4

AKI stage 3

Question 5

Outline the STOP: AKI mnemonic for the causes of AKI

Answer 5

• Sepsis + hypoperfusion
• Toxicity
• Obstruction
• Parenchymal kidney disease

Question 6

What are drugs to look out for?

Answer 6

CANDA:

• Contrast media
• Acei
• NSAIDs
• Diuretics
• ARBs

Question 7

Would you stop aspirin dose of 75mg OD in a patient with AKI?

Answer 7

NO unless has GI bleed

Question 8

Outline the sick day rules

Answer 8

• If vom/di, fever, sweats + shaking
• Stop: ACEi, ARBs, NSAIDs, Diuretics + metformin
• Restart after 24-48hrs eating + drinking normally

Question 9

Why must NSAIDs be stopped when a patient has a sick day?

Answer 9

• Impair renal autoregulation
• Inhibit prostaglandin-mediated vasodilation of afferent arteriole
• Inc risk of AKI

Question 10

Why must ACEi, ARBs + diuretics be stopped when a patient has a sick day?

Answer 10

• Cause volume contraction
• Inc risk of AKI by red glomerular perfusion