What is the normal saturation of oxygen (SaO2) in the blood?

The normal saturation of oxygen in the blood, referred to as arterial oxygen saturation (SaO2), typically falls within the range of 95% to 100%. This value represents the percentage of hemoglobin binding sites in the bloodstream that are occupied by oxygen.

A saturation level of 95% indicates that 95% of hemoglobin is saturated with oxygen, which is generally considered adequate for normal physiological function. When SaO2 levels drop below this range, it may indicate hypoxemia, which can necessitate further medical assessment or intervention.

While some sources may cite a lower threshold of 90% to 92% as acceptable in certain populations, especially those with chronic respiratory conditions, the most universally recognized normal range for healthy adults is indeed 95% to 100%. This is critical for ensuring optimal oxygen delivery to tissues and maintaining overall metabolic function. Thus, selecting this range accurately reflects the generally accepted values in medical practice.