A 45-year-old man with a history of poorly controlled type 2 diabetes mellitus presents with generalized weakness and muscle cramps. His laboratory results show: Na 138 mEq/L, K 6.8 mEq/L, Cl 102 mEq/L, HCO3 20 mEq/L, BUN 45 mg/dL, Cr 3.2 mg/dL. ECG shows peaked T waves. Which of the following is the most appropriate immediate intervention?
✓ Correct Answer: Option D
Intravenous calcium gluconate is the immediate intervention for severe hyperkalemia with ECG changes (peaked T waves) to stabilize the cardiac membrane and prevent life-threatening arrhythmias. Insulin and dextrose shift potassium intracellularly, and polystyrene sulfonate removes potassium more slowly.