Oxygen saturation is a crucial measure of how well the lungs are working. When we breathe in air, our lungs transmit oxygen into tiny blood vessels called capillaries. In turn, these capillaries send oxygen-rich blood to the heart, which then pumps it through arteries to the rest of the body. 

Our organs need a constant supply of oxygen to work properly. When the capacity of the lungs to transport oxygen into the blood is impaired, blood oxygen saturation declines, potentially putting our organs in danger. A pulse oximeter can quickly detect this drop in oxygen saturation, alerting people of the need for medical intervention.