What is the normal range for blood oxygen levels?

Blood oxygen generally refers to blood oxygen saturation, which is normally categorized into arterial blood oxygen saturation and venous blood oxygen saturation. The normal range for arterial blood oxygen saturation is typically between 95% and 98%, while the normal range for venous blood oxygen saturation is generally between 64% and 88%. If concerned, it is advisable to seek medical consultation in advance. Detailed explanations are as follows:

Arterial blood oxygen saturation reflects the percentage of oxygenated hemoglobin relative to total hemoglobin in arterial blood. The normal value is typically between 95% and 98%, making it an important indicator for determining whether the body is experiencing hypoxia. When arterial blood oxygen saturation falls below 95%, it may indicate hypoxia.

Venous blood oxygen saturation reflects the percentage of oxygenated hemoglobin relative to total hemoglobin in venous blood. Since venous blood has already passed through tissues and released oxygen, its oxygen saturation is typically lower than that of arterial blood, generally between 64% and 88%. When venous blood oxygen saturation drops below 64%, it may also suggest the presence of hypoxia.

When measuring blood oxygen saturation, it is important to remain calm and breathe normally, avoiding emotional excitement, breath-holding, or other behaviors that may affect the accuracy of the measurement.