Blood oxygen saturation range
Normal oxygen saturation (SpO2) is between 95% and 100% in both adults and children.
Oxygen saturation below 95% is considered abnormal, and the brain may be affected when SpO2 levels drop below 80% to 85%. Cyanosis of the skin or mucous membranes occurs when SpO2 levels fall below 67%.
However, older adults typically have slightly lower blood oxygen saturation levels than younger adults and children. People over 70 may have oxygen levels close to 95%, which is normal for this age group, while infants and children have normal SpO2 rates of 97% or higher.
Low levels of oxygen in body tissues are called hypoxia. Low oxygen levels in the blood are called hypoxemia. Hypoxia and hypoxemia can occur separately, although they often occur together because when blood oxygen levels are low, the blood cannot deliver enough oxygen to the body's tissues. Hypoxia is often used to describe low oxygen in body tissues as well as low blood oxygen.
Reference chart of normal blood oxygen saturation in different age groups
(Health) Status SpO2 Level
Normal adults and children 95% to 100%
Abnormal (brain may be affected) 80% to 85%
Skin becomes cyanotic below 67%
What are the symptoms of low oxygen saturation?
Signs and symptoms of low oxygen saturation (hypoxia and/or hypoxemia) include:
Difficulty breathing
Cyanosis
Deeper and faster breathing
a severe drop in blood pressure
dizzy
Rapid heart rate, arrhythmia
Indigestion, loss of appetite
Convulsions and coma, etc.
Hypoxemia is a medical emergency. If symptoms of hypoxia occur, please seek medical attention in time.