In COPD patients on oxygen therapy, ABGs are monitored as needed to assess what?

• A. To assess oxygenation and CO2 retention.
• B. To measure liver function.
• C. To evaluate acid-base only in chronic kidney disease.
• D. To monitor white blood cell count.

Answer: (A)

ABG monitoring in COPD patients on supplemental oxygen focuses on how well oxygen is getting into the blood and whether CO2 is being retained. An arterial blood gas provides PaO2 and PaCO2, along with pH and bicarbonate, giving a clear view of gas exchange and acid-base status. In COPD, adding oxygen helps correct low oxygen levels but can worsen CO2 retention in some individuals, so ABGs are used to balance adequate oxygenation with avoiding hypercapnia. This testing guides adjustments to oxygen therapy and can reveal when ventilatory support or other interventions are needed. The other options don’t reflect the purpose of ABG testing here, since they relate to liver function, white blood cell counts, or kidney disease rather than gas exchange and acid-base balance.