Which statement reflects a contraindication to oxygen therapy?

• A. None
• B. Pneumothorax
• C. Hypertension
• D. Anemia

Answer: (A)

The main idea here is that supplemental oxygen is broadly safe and used whenever there’s a risk of hypoxia, with very few true contraindications. Pneumothorax is not a reason to withhold oxygen; in fact, high oxygen can help speed reabsorption of intrapleural air, and oxygen is routinely given in suspected or known pneumothorax as part of standard care. Hypertension is not a contraindication—oxygen won’t inherently worsen high blood pressure, though oxygen should be used with clinical judgment as for any patient with cardiovascular disease. Anemia isn’t a contraindication either; oxygen can improve tissue oxygen delivery temporarily even though it doesn’t treat the underlying anemia. The absence of a real contraindication means there isn’t a condition listed here that would preclude giving oxygen, so the correct stance is that there are none. (Note: in some conditions, like COPD with chronic CO2 retention, oxygen requires careful titration to avoid hypoventilation, but that’s a dosing consideration rather than a contraindication.)