In COPD patients, what is the recommended oxygen saturation target and the upper limit to avoid hyperoxia?

• A. Maintain SPO2 at 100% with no upper limit.
• B. Maintain SPO2 at 93% with a maximum of 94%.
• C. Maintain SPO2 at 95% with a maximum of 96%.
• D. Maintain SPO2 at 90% with a maximum of 91%.

Answer: (D)

In COPD with chronic CO2 retention, the goal of oxygen therapy is to provide enough oxygen without suppressing the drive to breathe. Too much oxygen can blunt the hypoxic drive and worsen CO2 retention, leading to acidosis and potential respiratory failure. Because of this, oxygen is titrated to a narrow target range rather than 100% saturation.

A common and effective target is around 90% saturation, with a strict upper limit just above that to avoid hyperoxia. Keeping SpO2 near 90% and not rising above about 91% helps maintain adequate oxygen delivery while minimizing the risk of CO2 retention. In practice, start with a modest oxygen flow and adjust to keep SpO2 in that small window, using continuous pulse oximetry and reassessing as the patient’s condition changes.