Pulse oximeters, devices used for estimating blood oxygen levels, may be less accurate in people with darker skin pigmentation, the FDA warns. The tools are often used by patients at-home to monitor conditions, however the FDA cautioned that the technology have limitations and a risk of inaccuracy under certain conditions.

Today many pulse oximeters are digitally connected, which has made the device popular for remote monitoring.

While the agency doesn't explicitly mention race, it cites a recent report published in The New England Journal of Medicine, which found, in two large cohorts of patients, “Black patients had nearly three times the frequency of occult hypoxemia that was not detected by pulse oximetry as white patients.”

The agency went on to detail that poor circulation, skin pigmentation, skin thickness, skin temperature, the use of tobacco and fingernail polish can all have an effect on the device’s accuracy. 

"Pulse oximeters have limitations and a risk of inaccuracy under certain circumstances. In many cases, the level of inaccuracy may be small and not clinically meaningful; however, there is a risk that an inaccurate measurement may result in unrecognized low oxygen saturation levels. Therefore, it is important to understand the limitations of pulse oximetry and how accuracy is calculated and interpreted," the agency wrote. 

The agency is now taking action to look into possible issues with the devices. 

"The FDA is evaluating published literature pertaining to factors that may affect pulse oximeter accuracy and performance, with a focus on literature that evaluates whether products may be less accurate in individuals with darker skin pigmentation," the release read. 

It also pledged to continue work on the analysis of premarket data, and work with stakeholders to analyze the post-market data. 

WHY IT MATTERS

Over the last year the pulse oximeter has been used to remotely monitor patients with COVID-19. It is also important to note that according to the CDC, evidence suggests ethnic minority groups are disproportionately affected by COVID-19.

Historically, there has been a large gap in representation in clinical trials. Namely, women and people of color have not been representative in the research.

In 2020, the FDA rolled out a new guidance, called Enhancing the Diversity of Clinical Trial Populations – Eligibility Criteria, Enrollment Practices and Trial Designs, aimed at boosting the number of underrepresented populations in clinical trials. 

THE LARGER TREND

Connected pulse oximeters are plentiful today. In September, Masimo scored 510(k) clearance for its Rad-G pulse oximeter that can be used to spot-check or continually monitor patients.

We’ve also seen digital health companies expand beyond the traditional pulse oximeter. For example, California-based Beddr launched its Sleep Turner, which is a sleep sensor worn on the forehead that can measure blood oxygenation, heart rate and sleep position.