Pulse oximeter accuracy and limitations

FDA warned Friday that while pulse oximeters have increased in use during the COVID-19 pandemic, they may not always be accurate. In a Safety Communication, the agency noted the devices are “useful for estimating blood oxygen levels” but “have limitations and a risk of inaccuracy under certain circumstances that should be considered.” FDA said: “Be aware that multiple factors can affect the accuracy of a pulse oximeter reading, such as poor circulation, skin pigmentation, skin thickness, skin temperature, current tobacco use, and use of fingernail polish.” A recent letter in the New England Journal of Medicine found that Black patients may not receive accurate readings from some pulse oximeters. FDA noted that although the retrospective study had certain limitations, it “agrees that these findings highlight a need to further evaluate and understand the association between skin pigmentation and oximeter accuracy.” FDA’s communication reviews how to take a reading with a pulse oximeter, how to interpret a reading, and when patients should contact their health care providers. “Patients with conditions such as COVID-19 who monitor their condition at home should pay attention to all signs and symptoms of their condition and communicate any concerns to their health care provider,” FDA said.