— 生理適應 · MEDIUM · MCQ —
一位 COPD 病人出現呼吸性酸中毒。其原因為何？
A client with chronic obstructive pulmonary disease (COPD) develops respiratory acidosis. What is the cause?
- AInadequate alveolar ventilation✓ 正解肺泡通氣不足
- BExcessive intake of bicarbonate過量攝取碳酸氫鹽
- CHyperventilation過度換氣
- DDiuretic therapy利尿劑治療
— Explanation · 中文詳解 —
呼吸性酸中毒（Respiratory Acidosis）的根本機轉為二氧化碳（CO2）排出不足，導致血液中碳酸濃度上升，pH 值下降。對於慢性阻塞性肺病（COPD）病人，因長期氣道阻塞、氣囊過度膨脹及肺泡彈性喪失，導致肺泡換氣（Alveolar ventilation）能力顯著下降，無法有效排出代謝產生的 CO2，進而引發酸中毒。
The fundamental mechanism of respiratory acidosis is inadequate elimination of carbon dioxide (CO2), leading to increased carbonic acid in the blood and a decrease in pH. In clients with COPD, chronic airway obstruction, alveolar hyperinflation, and loss of alveolar elasticity significantly reduce alveolar ventilation, preventing effective elimination of metabolic CO2 and resulting in acidosis.