Measurement of skin tone confirms inaccuracy of pulse oximeters in some people, Elizabeth Tracey reports


Just how inaccurate are the devices used to measure oxygen in the blood, called pulse oximeters, in people with darker skin? That’s the question that Ashraf Fawzy, a critical care medicine expert at Johns Hopkins, and colleagues addressed in a recent study.

Fawzy: There is a gradation of how inaccurate the pulse oximeter is based on the skin pigmentation. We measured skin pigmentation using a colorimeter, a handheld device that measures the light reflectance off of the skin and that correlated with melanin levels. And we showed that those with darker skin pigmentation that is objectively measured has worse accuracy of pulse oximeters. We had a pretty small sample and this needs to be done in much broader samples.   :29

Fawzy says pulse oximeters were developed decades ago and really haven’t changed much at all over the years. The problem of inaccuracy in those with darker skin was very apparent during the pandemic, and now points clearly to the need to update the technology, which is vital for many hospitalized people. At Johns Hopkins, I’m Elizabeth Tracey.