apnea guy sleeping very well

Here is what no one tells you about Pulse Oximetry

Pulse oximetry is the non-invasive measurement of a person’s oxygen saturation, the value expressed is SpO2. The most common forms of SpO2 testing is with a sensor attached to the finger, earlobe (pediatric application is often on the child’s toe), or forehead (reflectance testing). It is important to understand that perfusion, skin pigmentation and thickness, ambient light sources and nail polish and acrylic nails all will affect the acuity of pulse oximetry or SpO2 testing.