What device is used to measure the oxygen level in arterial blood?

The device used to measure the oxygen level in arterial blood is a pulse oximeter. This small, non-invasive tool works by shining light through a relatively thin part of the body, typically a fingertip or earlobe, and detects changes in light absorption that correlate with the level of oxygen bound to hemoglobin in the blood. This allows healthcare professionals to quickly assess a patient’s oxygen saturation levels, which is vital for monitoring respiratory health and ensuring proper oxygen delivery throughout the body.

In contrast, a stethoscope is designed primarily for listening to internal body sounds, such as heartbeats and lung sounds, but does not provide information about oxygen saturation. A sphygmomanometer measures blood pressure in the arteries and is not related to oxygen levels. A thermometer is used to measure body temperature, serving a different purpose entirely. Each of these devices has distinct functions within the healthcare field, but only the pulse oximeter provides vital information regarding oxygen levels in the bloodstream.