Final answer:
Pulse oximetry is measured in percent saturation and uses sensors on a thin body part like a fingertip to determine blood oxygen levels. Normal readings are between 95-100%, and the method provides insights into metabolic rate and respiratory health.
Step-by-step explanation:
Pulse oximetry is measured in terms of percent saturation of oxygen in the blood. Sensors for a pulse oximeter are typically placed on a thin part of the body, such as the tip of the finger, where they can measure light absorption by hemoglobin to calculate oxygen saturation. Normal readings for pulse oximetry range from 95-100 percent saturation. Lower readings may indicate hypoxemia, or low blood oxygen levels. In addition to pulse oximetry using a sensor on the finger, oxygen levels can be measured directly from the plasma, typically after an arterial stick, and are expressed in terms of partial pressure of oxygen (pO2), which is recorded in millimeters of mercury (mm Hg).
Understanding oxygen saturation is critical for assessing a person's metabolic rate and can reveal information about their athletic conditioning or detect certain medical problems. It is a non-invasive measure that provides immediate feedback about the efficiency of a person's oxygen use and respiratory function.