Blood oxygen levels refer to the amount of oxygen circulating in the blood. Normal blood oxygen levels fall between 75 and 100 millimeters of mercury (mm Hg) on arterial blood gas (ABG) test results.

Lindsay Modglin is a nurse and professional writer who regularly writes about complex medical topics, as well as travel and the great outdoors. She holds a professional certificate in scientific ...

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The blood oxygen sensor featured in Apple Watch Series 6 and 7 is “not intended for medical use,” Apple says. That seems odd, considering that low blood oxygen is a serious medical condition. If the ...

The severity of COVID-19 pneumonia can be difficult to assess in people from different ethnic groups, due to inaccurate readings from a device that measures the level of oxygen in the blood of ...