An 8-year-old with chronic salt-wasting tubulopathy has potassium 2.4 mmol/L, magnesium 0.46 mmol/L, metabolic alkalosis and ventricular ectopy.

Question

An 8-year-old with chronic salt-wasting tubulopathy has potassium 2.4 mmol/L, magnesium 0.46 mmol/L, metabolic alkalosis and ventricular ectopy. Urine output is established. Which immediate principle is most important?

Accepted Answer

Replace potassium with cardiac monitoring and correct the accompanying magnesium deficit

Answer

Delay replacement until genetic testing distinguishes Bartter from Gitelman syndrome

Answer

Administer sodium bicarbonate to correct the alkalosis before replacing electrolytes

Answer

Correct potassium alone because magnesium status does not affect renal potassium wasting

Answer

Give a rapid undiluted intravenous potassium bolus before checking urine output

Bartter syndrome — RACP Paediatrics MCQ

An 8-year-old with chronic salt-wasting tubulopathy has potassium 2.4 mmol/L, magnesium 0.46 mmol/L, metabolic alkalosis and ventricular ectopy. Urine output is established. Which immediate principle is most important?