Pulse Oximetry Summary
Pulse oximetry is the non-invasive ...

Pulse Oximetry Summary
Pulse oximetry is the non-invasive continuous measurement of the oxygen saturation of hemoglobin. It exploits the fact that oxy- & deoxy hemoglobin differentially absorb red and infra-red light.
Shine Red and IR light through the skin and measure the absorption → DeoxyHb and OxyHb have different light absorption profiles → The signal that varies with time represents the pulsatile blood flow. Using a standard curve, the ratio of Red/IR absorption (modulation ratio) is used to calculate the SaO2 
The plethysomograph waveform shows signal over time, corresponding to pulse
Amplitude may increase with greater SV (such as after a pause)
Perfusion index indicates the signal strength

Nick Mark MD @nickmmark

#Pulse #Oximetry #Summary #critcalcare #pathophysiology #diagnosis 
Contributed by

Dr. Gerald Diaz
Board Certified Internal Medicine Hospitalist, GrepMed Editor in Chief 🇵🇭 🇺🇸 - Sign up for an account to like, bookmark and upload images to contribute to our community platform. Follow us on IG:  https://www.instagram.com/grepmed/ | Twitter: https://twitter.com/grepmeded/
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