Certified Medical Assistant Practice Exam 2026 - Free CMA Practice Questions and Study Guide

The device used to measure oxygen saturation levels is the pulse oximeter. This non-invasive tool works by passing a beam of light through the skin, usually on a fingertip, to estimate the amount of oxygen being carried in the blood. It provides a quick and effective way to monitor a patient’s respiratory status, making it an essential instrument in various healthcare settings. Pulse oximeters can give immediate feedback, allowing healthcare professionals to assess the effectiveness of oxygen therapy or detect potential respiratory issues.

Other devices listed do not directly measure oxygen saturation. A cardiac monitor primarily tracks heart rate and rhythm, a blood pressure cuff measures blood pressure levels, and a respiratory monitor focuses on the rate and depth of breathing, but none of these provide information about oxygen saturation specifically.