With COPD, excessive oxygen therapy drives which condition and can contribute to respiratory what?

With COPD, excessive oxygen therapy drives which condition and can contribute to respiratory what?

• A. Hypercapnia
• B. Hypoxemia, metabolic alkalosis
• C. Hyperoxia, respiratory alkalosis
• D. Dehydration, metabolic acidosis

Answer: (A)

In COPD, breathing is often driven more by low oxygen levels than by CO2 buildup, so giving too much oxygen can blunt the natural drive to breathe. This can lead to hypoventilation and a rise in blood CO2, i.e., hypercapnia. The excess CO2 causes respiratory acidosis because CO2 forms carbonic acid in the blood, lowering pH. So, excessive oxygen therapy tends to drive hypercapnia and can contribute to respiratory acidosis. That’s why oxygen is carefully titrated to a modest target (often around 88–92% saturation) to avoid suppressing ventilation while still correcting hypoxemia.

In COPD, breathing is often driven more by low oxygen levels than by CO2 buildup, so giving too much oxygen can blunt the natural drive to breathe. This can lead to hypoventilation and a rise in blood CO2, i.e., hypercapnia. The excess CO2 causes respiratory acidosis because CO2 forms carbonic acid in the blood, lowering pH. So, excessive oxygen therapy tends to drive hypercapnia and can contribute to respiratory acidosis. That’s why oxygen is carefully titrated to a modest target (often around 88–92% saturation) to avoid suppressing ventilation while still correcting hypoxemia.