Final answer:
Oxygenation at the cellular level in body tissues is commonly measured using a pulse oximeter calculating percent saturation or through arterial blood gas (ABG) analysis to assess the partial pressure of oxygen (pO2).
Step-by-step explanation:
To determine oxygenation at the cellular level in body tissues, the most widely used test is the measurement of percent saturation using a pulse oximeter. This device calculates the percentage of hemoglobin binding sites in the blood that are occupied by oxygen. Pulse oximeters function by emitting two wavelengths of light through a thin part of the body, such as a fingertip, and then using a photodetector to measure the light absorption difference, which varies based on the hemoglobin's oxygen saturation
arterial blood gas (ABG) analysis measures the partial pressure of oxygen (pO2) in the blood, providing direct monitoring of free oxygen in the plasma. This test gives information about the amount of oxygen dissolved in the blood and is expressed in millimeters of mercury (mm Hg). Both of these tests offer insights into the metabolic rate, the rate of food energy conversion, and can reveal various health and conditioning states.