Hyperkalaemia — UKMLA MCQ

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MediumRenal medicine & UrologyHyperkalaemiaUKMLA

A 63-year-old man with CKD stage 3 is found to have hyperkalaemia (K+ of 6.1 mmol/L). He has peaked T waves on ECG but is asymptomatic. Which medication should be administered first?

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Correct answer: B — Calcium gluconate IV

This patient has hyperkalaemia with ECG changes: K+ 6.1 mmol/L plus peaked T waves. ECG changes indicate myocardial toxicity and risk of malignant arrhythmia, so the first treatment is immediate IV calcium to stabilise the cardiac membrane. In a non-arrest/peri-arrest patient, this is IV calcium gluconate. Calcium does not lower serum potassium; after membrane stabilisation, potassium should be shifted intracellularly with IV insulin/glucose and/or nebulised salbutamol, and then removed from the body as appropriate. Sodium bicarbonate is reserved mainly for significant metabolic acidosis, and furosemide is not the immediate priority.

Reference: UK Kidney Association Clinical Practice Guideline: Management of Hyperkalaemia in Adults, 2023. https://guidelines.ukkidney.org/hyperkalaemia/