skip to main content

Hyperkalaemia Emergency — ESENeph MCQ

Instant feedback + full explanation. One question, done properly.

EasyElectrolyte DisordersHyperkalaemia EmergencyESENeph

A 45-year-old woman presents with a potassium of 6.8 mmol/L. ECG shows peaked T waves but no broad QRS. She is haemodynamically stable. After IV calcium gluconate, what is the most rapid-acting treatment to lower serum potassium?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: D — IV Insulin 10 units with 25 g glucose (50 mL of 50% dextrose)

After cardioprotection with calcium gluconate, the most rapid potassium-lowering treatment is IV insulin (10 units Actrapid with 25 g glucose). This stimulates cellular uptake of potassium via Na+/K+-ATPase activation, with onset within 15-30 minutes and peak effect at 30-60 minutes. Nebulised salbutamol (onset 15-30 min) is often used as an adjunct. Sodium bicarbonate is less effective alone. Ion-exchange resins take hours. Furosemide promotes renal excretion but onset is slower.

Reference: UK Renal Association 2020 – Hyperkalaemia Guideline; NICE CG169