病人血鉀值 2.8 mEq/L，哪項評估是優先的？
A client has a potassium level of 2.8 mEq/L. Which assessment is the priority?
- ABowel sounds腸鳴音
- BLung sounds肺部聽診音
- CHeart rhythm✓ 正解心律
- DSkin turgor皮膚彈性
低血鉀（Hypokalemia，血鉀 < 3.5 mEq/L）會顯著影響心肌的電生理機能，導致心肌細胞再極化延遲。在心電圖上，這可能表現為 U 波出現、T 波倒置、ST 段下陷，且極易引發嚴重的致命性心律不整（如心室顫動）。因此，對於低血鉀病人，心臟監測與心律評估是護理師的首要任務，以利於及時發現並處置心律異常。
Hypokalemia (serum potassium < 3.5 mEq/L) significantly affects the electrophysiology of the myocardium, causing delayed repolarization of cardiac cells. ECG changes may include the appearance of U waves, T-wave inversion, and ST-segment depression, and the patient is at high risk for life-threatening arrhythmias such as ventricular fibrillation. Therefore, in a client with hypokalemia, cardiac monitoring and assessment of heart rhythm are the nurse's top priority so that rhythm disturbances can be detected and treated promptly.