In this hospital, pulse oximeters went from overestimating to underestimating blood oxygen. Why?

Pulse oximeters gained prominence during the Covid-19 pandemic, offering anyone a handheld tool to take stock of their blood oxygen level.  But their newfound popularity also brought new attention to their limitations — several studies have shown that pulse oximeters overestimate blood oxygen levels when used on darker skin tones. This can make patients of color appear more healthy than they really are, resulting in worse health outcomes and exacerbated inequality. Read the rest…