一位 50 歲白血病女性病人在右側鎖骨下靜脈有中央靜脈導管（CVC）。護理師執行預定的無菌換藥與接頭更換。下列哪些介入可預防換接頭瞬間的空氣栓塞？（多選題）
A 50-year-old female with leukemia has a central venous catheter (CVC) in the right subclavian vein. The nurse is performing a scheduled sterile dressing and cap change. Which interventions prevent air embolism during the brief moment the line is open? (Select all that apply.)
- AHave the client perform the Valsalva maneuver (deep breath in, hold, bear down) when the cap is opened.✓ 正解當打開蓋子時，指示病人進行瓦爾薩爾瓦動作（深吸氣、屏氣、用力）。
- BInstruct the client to scream and hyperventilate to blow air away from the open lumen.指示病人尖叫並過度換氣，將空氣吹離開放的管腔。
- CHave the client turn their head and neck away from the insertion site (toward the opposite side).✓ 正解讓病人將頭部和頸部轉向插入部位的另一側（朝向對側）。
- DPosition the client in high-Fowler's at 90 degrees so gravity pulls air to the feet.將病人置於九十度的高福勒氏臥位，以便重力將空氣拉向腳部。
- EBoth the nurse and the client wear surgical masks throughout the procedure.✓ 正解護理師和病人在整個過程中都佩戴外科口罩。
CVC 換接頭時若有空氣吸入，可能造成致命的空氣栓塞。 選項 A 正確：Valsalva manuever 增加胸內壓，防止空氣被吸入靜脈。 選項 C 正確：頭轉向對側避免病人口鼻細菌污染敞開的導管接頭。 選項 E 正確：護理師與病人皆戴口罩降低呼吸道飛沫污染導管的風險。 選項 B 錯誤：尖叫過度通氣不會排空氣，反而引發胸內負壓吸氣，更危險。 選項 D 錯誤：應採平躺或 Trendelenburg 位（頭低腳高）— 高 Fowler's 位會增加胸內負壓吸入空氣。
Air embolism during CVC cap change is potentially fatal. A correct: Valsalva maneuver increases intrathoracic pressure, preventing air entry into the vein. C correct: Turning the head away from the site prevents oral/nasal contamination of the open hub. E correct: Masks on both nurse and client reduce respiratory droplet contamination. B incorrect: Screaming/hyperventilating creates negative intrathoracic pressure, drawing air in—more dangerous. D incorrect: Supine or Trendelenburg is correct; high-Fowler's increases negative pressure and air aspiration risk.
「Central Line (CVC/中央導管) = Valsalva Maneuver (憋氣用力下腹) + 出聲請病人轉出面向反側 + 一起戴口罩」。全世界各國護理標準技術作業流程完全一致！這更是國考極為熱愛的技術題幹核心。