Are pulse oximeters less accurate for people of color?
New studies suggest pulse oximeters are not calibrated to account for darker skin, resulting in overestimation of Black and Hispanic patients’ blood oxygen levels, raising the possibility they may not receive treatments they need
New studies call into question the accuracy of pulse oximeters in some people of color. The devices are not calibrated to account for darker skin tones so there is a risk that oxygen saturation levels in Asian, Black and Latino patients may be overestimated.
The inaccurate reading could result in some people of color not receiving needed supplemental oxygen or being prescribed COVID-19 treatments such as the antiviral remdesivir or the steroid dexamethasone.
The lead author of a new study published in the online Journal of the American Medical Association Internal Medicine, told NPR that the researchers’ analysis of pre-pandemic health data found pulse oximetry measurements resulted in patients of color receiving less supplemental oxygen than white patients.
“We were fooled by the pulse oximeter,” said the study’s lead author Dr. Leo Anthony Celi, clinical research director and principal research scientist at the MIT Laboratory of Computational Physiology.
“We were given the false impression that the patients were OK. And what we showed in this study is that we were giving them less oxygen than they needed,” he told NPR.
The study of 3,069 patients in an intensive care unit found that Asian, Black and Hispanic patients had a higher adjusted time-weighted average pulse oximetry reading and were administered significantly less supplemental oxygen for a given average hemoglobin oxygen saturation compared with white patients.
“There were differences in supplemental oxygen administration between Asian, Black and Hispanic patients and white patients that were associated with pulse oximeter performance and may contribute to racial and ethnic disparities in care,” the study states.
It continues, “further research is needed to confirm these findings and explore other clinical factors associated with treatment disparities.”
Pulse oximetry is a painless, noninvasive method of measuring the saturation of oxygen in a person’s blood. Oxygen saturation indicates how well the lungs are working.
Pulse oximeters took on an even more significant role in hospitals and homes during the COVID-19 pandemic.
Earlier this year, in a KSL-TV report, Dr. Wing Province, an emergency physician and medical director of Intermountain Park City Hospital, recommended that Utahns obtain a pulse oximeter for home use should they become ill with COVID-19 symptoms.
“If your oxygen levels are less than 90%, then I would say you should come to an emergency department, or call 911,” he said.
While new studies reflect pulse oximeters may be less accurate in some patients of color, health care providers can also draw blood to measure oxygen saturation so they are not solely reliant on the devices.