Study: Medical devices have been shown to provide inaccurate readings for non-white patients

University of Manitoba professors discover that a commonly used medical care device is providing inaccurate results on patients of color, prompting doctors to take potentially harmful measures.

In July, Dr. Barret Rush, assistant professor of critical care, and Dr. Jennifer Zielger, critical care fellow, both in the department of internal medicine at Max Rady College of Medicine at the University of Manitoba (UM), a study shows Black, Asian and Hispanic patients receive less supplemental oxygen than white patients.

The study called Assessing racial and ethnic disparities in oxygen delivery in ICU patientswas then released this month in JAMA Internal Medicine and was by Dr. Eric Raphael Gottlieb and Dr. Leo Celi from Harvard Medical School and the Massachusetts Institute of Technology.

A media release UM sent out on Aug. 3 said they determined the discrepancy was related to a design flaw in the fingertip device used to measure oxygen levels in the blood. The oxygen level in a patient’s blood is measured by the device, which produces a beam of light through the finger once it is clipped onto the finger.

The device is already known to provide inaccurate readings due to pigmentation, whether it’s skin color or nail polish. The study by Dr. rush and dr However, Ziegler is the first to gather evidence of the impact on patient care.

The press release even states that there have been “several studies that have shown that pulse oximeters overestimate oxygen levels in non-white patients.”

“This shows that systemic racism is built into the technology we use and impacting minority health outcomes,” Rush says. “Not only does our medical technology provide us with biased and incorrect information, but clinicians use this inaccurate information to make clinical decisions that cause harm.”

Elements of the study included reviewing anonymous data from more than 3,000 critically ill patients admitted to an intensive care unit at a Boston, Massachusetts hospital from 2008 to 2019. dr rush and dr Ziegler found that pulse oximeters overestimated the oxygen levels of Black, Asian, and Hispanic patients and that the patients were receiving less oxygen than they should have.

It was this discovery that allowed the two doctors to continue their studies.

The history of oximeters is that they were developed in the 1970’s and trials of the device were conducted on mostly healthy white male patients. dr Rush focuses his research on health disparities in critical care and suggests that a recalibration of the medical device is in order.

“Technology should be objective. But we found that she still has prejudices against non-white patients and that she contributes to overall poorer outcomes for non-white patients,” he says. “Our ultimate goal is to identify barriers and improve patient outcomes for these patients.”

Patient data included results from both pulse oximeters and laboratory tests, and the research team compared the results of both methods by measuring blood samples. The result was that black patients received less supplemental oxygen for a given oxygen saturation level, likely due to erroneous oximeter readings.

“Pulse oximeters are in every ward, clinic, and emergency room,” says Dr. Ziegler, who focuses her research on epidemiology and the use of “big data” in healthcare. “They contribute to worse outcomes in non-white patients. That should change.”

The next steps include Dr. rush and dr Ziegler along with her Boston colleagues consulting with bioengineers in the US to discuss solving the problem of racial bias in pulse oximeter technologies.

This discovery has led to media attraction from around the world such as CNN, BBC, NPR, Reuters, Good morning America and over 100 other news agencies.