Source: ABC News Online
Pulse oximeters, medical devices used in battling COVID-19, may not work effectively on people of color, according to health officials.
The small devices clamp onto a patient’s finger and measure oxygen levels in blood. During the pandemic, they’ve been used by people at home and in hospitals to monitor COVID-19 patients as the virus attacks the lungs, often leading to a drop in oxygen levels.
“The devices may be less accurate in people with dark skin pigmentation,” The U.S. Food and Drug Administration (FDA) has said in a statement. Pulse oximeters use infrared light beams to estimate the oxygen saturation of the blood and pulse rate, and darker skin pigment may absorb some of that light and alter results.
Black patients are nearly three times as likely to have dangerously low blood oxygen levels go undetected by pulse oximetry compared with white patients, the FDA said, citing December research.
“Melanin is a primary light absorber in the skin, and it’s going to absorb the light. This abounds more in individuals with darker skin,” Dr. Panagis Galiatsatos, an assistant professor in the Division of Pulmonary & Critical Care Medicine at Johns Hopkins, told ABC News. “These devices were evaluated on a certain population. It doesn’t take into account confounders like darker skin. We’d love to calibrate for darker skin variations — it’s just never been done before.
Other factors that affect the accuracy of pulse oximeters include skin temperature and thickness, tobacco use and the use of fingernail polish.
The Centers for Disease Control and Prevention has updated its coronavirus clinical guidance to flag that skin pigmentation may adversely affect results.
Pulse oximeters are popular because they’re a painless way to measure blood oxygen levels. Their sales skyrocketed during the pandemic even though studies from 2005, 2007 and 2020 found that the devices “provide misleading measures of blood oxygen levels to patients of color.”
Black and Hispanic individuals are twice as likely to die from COVID-19 as white Americans and three times more likely to be hospitalized with the virus.