A PaO2 of 60 mmHg corresponds to an approximate SpO2 of what percentage?

• A. 80%
• B. 85%
• C. 90%
• D. 95%

Answer: (C)

In assessing the relationship between arterial oxygen partial pressure (PaO2) and oxygen saturation (SpO2), the use of the oxygen-hemoglobin dissociation curve is crucial. A PaO2 of 60 mmHg typically corresponds to an SpO2 around 90%.

At this level of PaO2, hemoglobin is sufficiently bound with oxygen, allowing for adequate oxygen delivery to tissues. This value usually indicates that the patient may have mild hypoxemia, where the oxygen saturation remains tolerate but not ideal. Understanding this relationship is significant in clinical settings, where monitoring oxygen levels critically aids in assessing respiratory health.

Higher PaO2 values correspond to higher SpO2 percentages, while lower values lead to decreased saturation. In the context of the provided responses, choices above and below 90% do not accurately reflect this clinical correlation at a PaO2 of 60 mmHg, reinforcing that 90% is the most appropriate answer.