護理師照護一位錯過透析治療的末期腎病（ESRD）病人。病人的鉀離子值為 7.2 mEq/L，心電圖顯示 T 波高尖。哪項處置是保護心臟免於心律不整的最優先措施？
A nurse is caring for a client with end-stage renal disease (ESRD) who missed their last dialysis treatment. The client's potassium level is 7.2 mEq/L, and the ECG shows peaked T waves. Which intervention is the highest priority to protect the heart from dysrhythmias?
- AAdminister IV regular insulin with 50% dextrose靜脈注射常規胰島素併用 50% 葡萄糖
- BInitiate emergent hemodialysis開始緊急血液透析
- CAdminister Sodium Polystyrene Sulfonate (Kayexalate)口服硫酸鈉聚苯乙烯磺酸鹽 (Kayexalate)
- DAdminister IV Calcium Gluconate✓ 正解靜脈注射葡萄糖酸鈣
高血鉀（Hyperkalemia）是腎衰竭病人最危險的生理適應問題。當血鉀高達 7.2 mEq/L 並出現心電圖變化（如 T 波高尖）時，病人面臨致命性心律不整（如心室顫動）的立即風險。臨床決策的優先順序應是：穩定心肌（Stabilize）→ 轉移鉀離子（Shift）→ 移除鉀離子（Remove）。IV Calcium Gluconate（葡萄糖酸鈣）的作用是提高心肌細胞的動作電位閾值，對抗鉀離子對心臟的毒性，雖不降血鉀，但能「保命」。Insulin/Dextrose（A）能將鉀移入細胞內，是第二步。Kayexalate（C）排鉀慢且效果不可靠。洗腎（B）是最終移除鉀的手段，但準備機器需要時間，在等待期間必須先穩定心肌防止心跳停止。
Hyperkalemia is the most dangerous physiologic adaptation problem in clients with renal failure. When the potassium level reaches 7.2 mEq/L and ECG changes (such as peaked T waves) are present, the client faces an immediate risk of lethal arrhythmias (such as ventricular fibrillation). Clinical priorities follow the sequence Stabilize → Shift → Remove. IV calcium gluconate raises the myocardial cell action potential threshold and counteracts the cardiotoxic effects of potassium; although it does not lower the serum potassium, it 'saves the life.' Insulin/dextrose (A) shifts potassium into the cells and is the second step. Kayexalate (C) removes potassium slowly and unreliably. Hemodialysis (B) is the definitive means of removing potassium, but setting up the machine takes time; in the interim, the myocardium must first be stabilized to prevent cardiac arrest.
美國 NCLEX 考題極度強調「穩定心肌」優於「降鉀」的邏輯順序。在台灣臨床實務中，醫師通常會同時開立 Calcium、RI/D50W 及緊急洗腎照會，護理師需敏銳察覺心電圖變化並在藥物到達後立即施打。美國護理師在 ACLS 規範下對於此類高鉀急症的處置流程（Protocol）執行權限較大。