A nurse is caring for a client who has acute kidney injury and a potassium level of 6.5 mEq/L (3.5 to 5 mEq/L). Which of the following electrocardiogram (ECG) changes should the nurse expect?

Rationale: A. Prominent P waves: Hyperkalemia typically causes a decrease in P wave amplitude and can eventually lead to their disappearance, rather than making them more prominent. Prominent P waves are not characteristic of elevated potassium levels. B. Narrowed QRS complexes: Hyperkalemia often leads to a widening, not narrowing, of the QRS complex as potassium levels rise. A narrowed QRS complex is not a hallmark finding in clients with elevated potassium. C. Shortened PR intervals: Hyperkalemia is more commonly associated with prolonged PR intervals. A shortened PR interval is not typically seen in potassium imbalance and would be more relevant in other conduction abnormalities. D. Peaked T waves: Tall, peaked T waves are the classic early ECG finding in hyperkalemia. They result from increased potassium altering myocardial repolarization and are often the first electrocardiographic sign of elevated serum potassium.