Study confirms racial bias with pulse oximeters

A new study in JAMA Pediatrics published March 20, 2023, suggests that pulse oximetry overestimated arterial oxygen saturation in Black children.

Among the study cohort of 774 white and Black children, a discordant finding of normoxemia by peripheral oxygen saturation levels on pulse oximetry (SpO₂ ≥92%), or a false negative, reached 12% of Black versus 4% of white patients. These children had true hypoxemia according to directly measured arterial blood oxygen saturation (SaO₂ <88%). However, among patients with normal SpO₂ readings, 5% of Black children and 1% of white children turned out to have hypoxemia by SaO₂.

“The discrepancy has been attributed to light absorption properties of melanin,” wrote the study authors. “Race is an imperfect proxy for skin pigmentation with the inherent assumption that Black or African American patients had darker skin and more melanin than white patients.”

Researchers suggest that future studies in children should prospectively evaluate the association between SpO₂ and SaO₂ with reliable, direct measurement of skin pigmentation.

Some previous studies conducted during the pandemic suggested that Black patients with COVID-19 may have experienced delays in care due to potentially inaccurate readings.

Back in November 2022 at a meeting to discuss ongoing concerns that pulse oximeters may be less accurate in individuals with darker skin pigmentations, an FDA panel said pulse oximeters are less accurate in patients with darker skin, and they urged FDA to notify patients and providers about the issue and recommend that manufacturers correct the discrepancy.