Your Guide to Interpreting Pulse Oximeter Readings

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Pulse oximetry measures how much oxygen is being carried by one’s blood throughout their body while their heart is pumping. So, how is this measured? Namely through pulse oximeters, small devices that are used in hospitals, clinics and homes to measure heart rate and blood oxygen saturation.

Unlike a clinical blood test, pulse oximeters allow for near-instant results — and they’re completely non-invasive. Simply slip the device on the end of your finger or toe and you’ll have results in seconds. First developed back in 1974 by Japanese bioengineer Dr. Takuo Aoyagi, pulse oximeters were made commercially available for at-home monitoring in 1995. Since then, personal pulse oximeters have allowed folks with lung, breathing and heart conditions to track their own readings and monitor their daily levels. So, how do these wondrous devices work?