下列哪位病人發生醫院獲得性肺炎的風險最高？
Which client is at the highest risk for developing hospital-acquired pneumonia?
- AA client on mechanical ventilation for 4 days✓ 正解接受機械通氣 4 天的病人
- BA client with a closed fracture of the tibia脛骨閉鎖性骨折的病人
- CA client receiving IV fluids for dehydration因脫水接受靜脈輸液的病人
- DA client with an indwelling urinary catheter留置導尿管的病人
醫院獲得性肺炎（HAP）的風險因素通常與呼吸道防禦機制被繞過有關。機械通氣（Mechanical ventilation）病人因為插管，氣管直接與外界相通，且無法有效咳嗽排痰，是發生呼吸機相關肺炎（VAP）的高風險群。比較其他選項，骨折、脫水或尿管留置雖然都有風險，但都不及人工氣道直接增加的肺部感染風險高。
Risk factors for hospital-acquired pneumonia (HAP) usually involve bypassing the respiratory defense mechanisms. Mechanically ventilated clients are intubated, with the trachea directly connected to the outside, and cannot effectively cough or clear secretions, making them at high risk for ventilator-associated pneumonia (VAP). Compared with the other options, fractures, dehydration, or an indwelling urinary catheter carry some risk, but none reach the level of pulmonary infection risk directly conferred by an artificial airway.