This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'Hyperkalemia without ECG changes may be treated with all except : \nSelect and explain. \nA. Calcium gluconate, B. Salbutamol, C. Na bicarbonate, D. Insulin with dextrose', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Calcium antagonizes the cardiac conduction abnormalities induced by potassium. In the given question, the patient has no ECG changes; therefore calcium gluconate will not be useful. Use of calcium gluconate should be restricted to life-threatening hyperkalemia.', 'role': 'assistant'}]