Acute kidney injury with hyperkalaemia — SCE Geriatric Medicine MCQ

Correct answer: C — Temporarily withhold ramipril, spironolactone and metformin while treating the AKI and hyperkalaemia

Explanation lettering: B = shown as A · D = shown as B · A = shown as C · C = shown as D

The correct answer is A. Current UK guidance on acute kidney injury management (Bradford Hospitals NHS AKI guideline) specifies that ACE inhibitors, potassium-sparing diuretics, and metformin should be temporarily withheld in AKI. This patient has three compelling reasons to withhold these drugs: (1) **Ramipril**: ACE inhibitors paradoxically increase AKI risk during sepsis and hypotension by causing unopposed efferent arteriolar vasodilation, reducing glomerular filtration pressure; this mechanism is particularly harmful in acute illness, unlike their chronic renoprotective role. (2) **Spironolactone**: A potassium-sparing diuretic absolutely contraindicated in hyperkalaemia (K⁺ 5.9 mmol/L). (3) **Metformin**: Contraindicated in AKI due to accumulation and risk of metformin-associated lactic acidosis. Ibuprofen gel (contributing to AKI) should also be reviewed. Option B incorrectly assumes long-term chronic renal protection applies during acute sepsis—the mechanism differs fundamentally. Options C and E are dangerous (increasing metformin in AKI; giving potassium supplements when hyperkalaemic). Option D is incorrect: AKI does not mandate permanent anticoagulation cessation.

Reference: Bradford Hospitals NHS Trust. Guidelines for the management and prevention of Acute Kidney Injury (AKI). 2019. https://www.bradfordhospitals.nhs.uk/wp-content/uploads/2019/06/AKI-guideline.pdf