pulse oximetry test

medicine

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July 20, 2026

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Pulse oximetry is a noninvasive medical method used to measure the oxygen saturation of arterial blood. It utilizes spectrophotometry, a technology that analyzes how much light is absorbed by oxygenated and deoxygenated hemoglobin. A sensor, typically attached to a finger, toe, or earlobe, detects pulsatile blood flow and provides a numerical percentage indicating the blood's oxygen level. This method replaced the more painful and time-consuming invasive arterial blood gas tests, which previously took 20 to 30 minutes to yield results. A pulse oximetry test is also referred to as pulse oximetries.12

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oxygen therapy
Flow rate
…gas (ABG) test and the pulse oximetry test. In the ABG test, blood is drawn from an artery, and blood acidity, oxygen, and carbon dioxide levels are measured. In pulse oximetry, a probe, generally placed over the end of a finger, is used to indirectly determine hemoglobin saturation—the percent of…
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…gas (ABG) test and the pulse oximetry test. In the ABG test, blood is drawn from an artery, and blood acidity, oxygen, and carbon dioxide levels are measured. In pulse oximetry, a probe, generally placed over the end of a finger, is used to indirectly determine hemoglobin saturation—the percent of…
Read More