護理師準備對心臟衰竭病人給予毛地黃（Digoxin）。在給藥前，哪項發現需要暫停給藥？
A nurse is administering digoxin to a patient with heart failure. Before giving the medication, which finding necessitates withholding the dose?
- ABlood pressure of 110/70 mmHg血壓 110/70 mmHg
- BApical pulse of 52 beats per minute✓ 正解心尖脈搏 52 次/分鐘
- CClient reports mild nausea客戶主訴輕微噁心
- DSerum potassium level of 4.2 mEq/L血清鉀濃度 4.2 mEq/L
Digoxin 具有正性心肌收縮力與負性心率變時作用（抑制房室傳導）。臨床給藥前必須確實測量心尖脈（Apical pulse）滿一分鐘。若心率過低（成人通常定義為 <60 bpm），給藥可能導致嚴重的心搏過緩或傳導阻滯。此外，低鉀血症會增加 Digoxin 中毒風險，故血清鉀離子濃度亦為重要監測項目。
Digoxin has both positive inotropic and negative chronotropic effects (by inhibiting AV conduction). Before clinical administration, the apical pulse must be measured for a full minute. If the heart rate is too low (typically defined as <60 bpm in adults), administration may cause severe bradycardia or conduction block. In addition, hypokalemia increases the risk of digoxin toxicity, so serum potassium concentration is also an important parameter to monitor.