A patient with chronic renal failure presents to the emergency department with symptoms of marked fatigue, confusion, and shortness of breath. The patient's current medications include calcium acetate, erythropoietin, and furosemide. Laboratory reports reveal hyperkalemia. What is the most appropriate initial management for this patient?
Give a bolus of intravenous fluids
Administer calcium gluconate
Start insulin and dextrose infusion
Oral administration of sodium polystyrene sulfonate