For a stable COPD patient with resting SpO2 of 89%, what is the target oxygen saturation range and when is long-term oxygen therapy indicated?

• A. Target SpO2 88-92%; LTOT indicated if PaO2 ≤55 mmHg or SpO2 ≤88% with hypoxemia-related complications
• B. Target SpO2 94-98%; LTOT indicated in all with O2
• C. Target SpO2 85-90%; LTOT indicated if FEV1 <30%
• D. Target SpO2 90-95%; LTOT never indicated

Answer: (A)

Oxygen therapy in stable COPD aims to keep resting oxygen saturation in a range that treats hypoxemia without causing harm from too much oxygen. The preferred target is 88–92% because this range provides enough oxygen delivery while avoiding the risk that higher oxygen levels can blunt the drive to breathe in chronic CO2 retainers and worsen hypercapnia.

Long-term oxygen therapy is shown to improve survival in patients with chronic hypoxemia, defined by a PaO2 of 55 mmHg or less, or an SpO2 of 88% or less on room air. It may also be indicated when PaO2 is 56–59 mmHg if there are signs of hypoxemia-related complications such as pulmonary hypertension or polycythemia. In this context, a resting SpO2 of 89% does not by itself trigger LTOT; it sits within the safe target range, and ongoing assessment with arterial blood gas or additional hypoxemia findings would guide LTOT decisions.

So the best choice reflects maintaining SpO2 in the 88–92% range and initiating LTOT only when there is more pronounced or clinically significant hypoxemia (PaO2 ≤55 mmHg or SpO2 ≤88% with complications).