Electrolyte Disorders USMLE Step 1 Practice Question
A 56-year-old woman with chronic kidney disease Stage 4 presents with diffuse muscle weakness and palpitations. Vital signs: BP 158/92, HR 104, RR 18, SpO2 98% on room air. ECG shows peaked T waves and prolonged PR interval. Serum potassium is 6.8 mEq/L, bicarbonate 19 mEq/L, creatinine 3.2 mg/dL. Urine output remains normal. She receives intravenous calcium gluconate. Which of the following best describes the primary purpose of this treatment?
Answer choices
- AEnhance urinary potassium excretion
- BShift potassium into cells
- CRemove potassium through the gastrointestinal tract
- DStabilize the cardiac membraneCorrect answer
- ECorrect the metabolic acidosis directly
- FF. Promote potassium binding to albumin in the serum
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