Final answer:
SaO2 and SpO2 are both measurements of oxygen saturation in the blood. SaO2 is measured directly from an arterial blood sample, while SpO2 is measured non-invasively using a pulse oximeter.
Step-by-step explanation:
The terms SaO2 and SpO2 both refer to the measurement of oxygen saturation in the blood.
SaO2, or arterial oxygen saturation, is measured directly from a blood sample taken from an artery. It represents the percentage of hemoglobin molecules in the arterial blood that are bound to oxygen.
SpO2, or peripheral oxygen saturation, is measured non-invasively using a pulse oximeter. It represents the percentage of hemoglobin molecules in the blood that are bound to oxygen, as measured at a peripheral site like the finger.