When SpO2 dips into the low 90s or below ... low blood oxygen levels persist for a long time or if your oxygen levels drop repeatedly. In severe cases, if your brain is getting less oxygen ...

Your SpO2 level should stay above 92% when sitting, walking, running, sleeping, and doing various physical activities.

Supplemental oxygen is commonly used in critically-ill patients to prevent hypoxemia (peripheral oxygen saturation [SpO2], < 88%), but excessive use can lead to hyperoxemia (SpO2, > 96% ...