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Oakland clinic gets medical device maker to disclose risk of false blood-oxygen reading

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Oakland clinic gets medical device maker to disclose risk of false blood-oxygen reading

-One of healthcare’s most fundamental tools works less reliably for people with darker skin tones.
– An Oakland clinic’s lawsuit is helping to change that in California.

The pulse oximeter, a device that measures the degree to which red blood cells are saturated with oxygen, is one of healthcare’s most fundamental tools.

So when Dr. Noha Aboelata learned that research stretching back decades showed that the devices routinely failed patients with darker skin tones, she took action.

Aboelata, the founder and chief executive of East Oakland’s Roots Community Health Center, urged the Food and Drug Administration to require makers of pulse oximeters to test their devices on people of color, and to warn consumers about the risk of false readings.

Attorneys for Roots wrote to companies that made or sold pulse oximeters in California, asking them to improve their products and disclose their limitations. When none responded, the clinic filed a lawsuit to force a change in practices.

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A year later, Roots and Aboelata are celebrating their first wins.

Minneapolis-based Medtronic, a leading provider of the devices to hospitals, reached a settlement with Roots last month.

Medtronic agreed to provide brochures and advisory labels on pulse oximeters sold to California hospitals, informing users that the devices can artificially inflate blood oxygen estimates on patients with darker skin. In exchange, Roots dropped its claims against the company.

In a statement, Medtronic said it “looks forward to working with Roots, the FDA and other key stakeholders to ensure health equity can be achieved through technology, educational efforts, and partnerships.”

Three other companies that sell directly to consumers also agreed to place informational labels on their products.

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The suit is proceeding against CVS, Walgreens, GE HealthCare and five other defendants that have not settled, Roots attorney Jonathan Weissglass said.

CVS and GE said they wouldn’t comment on pending legislation. Walgreens didn’t immediately respond for comment, but said earlier this year that it also would not comment on pending litigation.

The settlements are a step toward resolution for a pervasive yet frequently overlooked problem that has haunted medicine for decades.

“This pulse ox issue should never have been allowed to happen, and once it was known, it should not have been allowed to continue,” Aboelata said. “I’m still talking to people every week who don’t know about it.”

A pulse oximeter shines a light that passes through the patient’s skin, blood and tissues, and then measures how much light comes out the other side. They’re typically clipped on a fingertip.

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Before pulse oximeters were widely adopted in the 1980s, the only way to gauge a patient’s blood oxygen saturation was to draw blood from their arterial vein, a painful procedure that had to be followed by immediate laboratory analysis.

Oxygen-rich blood absorbs more infrared light. So does melanin, the pigment that helps determine skin, hair and eye color. As a result, patients with darker skin tones are more likely to get pulse oximeter readings that show their blood oxygen saturation to be higher than it actually is.

As early as 1990, researchers noted that Black patients were more likely to get deceptively high “pulse ox” readings when hypoxic, or suffering from low oxygen.

In 2005, UC San Francisco’s Hypoxia Research Laboratory found the devices were more likely to overestimate oxygen saturation in patients with dark skin than in those with light skin, results the lab confirmed in a follow-up study two years later.

Yet many providers — including those like Aboelata, who focused on addressing racial inequities in healthcare — were unaware of this data. This became a matter of life and death during the COVID-19 pandemic, when pulse oximeter readings became the primary metric hospitals used to determine who should get care.

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CDC guidelines instructed providers to start anyone with pulse ox readings below 90% on oxygen therapy.

A 2020 study of thousands of patients at the University of Michigan found that Black patients, compared with white patients, had nearly three times the rate of “occult hypoxia” — low blood oxygen that goes undetected because pulse oximeter readings are in the normal range.

After reading the study, a pharmacist and cardiologist from the University of Michigan looked at 204 patient records from their hospital.

In a study published in February, they found that Black patients’ blood oxygen readings on pulse oximeters were on average 6% higher than the actual blood oxygen levels measured in their arterial blood samples. In contrast, pulse oximeters overestimated white patients’ blood oxygen by just 1% on average.

Artificially high blood oxygen readings could lead physicians to underestimate how much blood is pumping from a patient’s heart or overestimate the degree of resistance in the patient’s vascular system, the researchers said.

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“Those sorts of measurements can impact how we care for patients with heart failure, and can impact their candidacy for more intense treatment options like heart transplants and heart pumps,” cardiologist Dr. Scott Ketcham said.

Currently, the FDA recommends — but doesn’t require — that pulse oximeter makers ensure that in their clinical trials, either two participants or 15% of total participants are “darkly pigmented” people, a definition open to interpretation.

In February 2021, the FDA issued a safety notice cautioning users that pulse oximeters can be thrown off by a number of variables, including skin pigment.

In February, an agency advisory panel recommended that the FDA require that new devices be tested on at least 24 people whose skin tones collectively span the Monk Skin Tone scale, a 10-color palette often used to train artificial intelligences to recognize people of different colors.

The proposal would divide the scale into three parts, with each part represented by at least 25% of study participants.

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Though the FDA indicated that it would issue new guidelines for pulse oximeter manufacturers by Sept. 30, it has not done so yet. The agency is working to release the updated guidance “as expeditiously as possible,” a spokesperson said.

The FDA also funded a study at UCSF’s Hypoxia Research Laboratory to better understand the relationship between skin pigment and pulse ox accuracy. The research team is preparing its results for publication now, said Dr. Phil Bickler, director of the UCSF lab and an investigator on the study.

Until then, making sure their devices work equally well for users of all skin tones is optional for manufacturers.

When Manhattan Beach-based BodiMetrics, a maker of wearable health monitors, sought FDA clearance for its most recent smart ring fitness tracker, the company opted to broaden the range of skin tones represented in its study population. One-third of its study population had darker skin pigment, compared with the FDA-recommended minimum of 15%.

“It’s a lot more money to do the clinical studies [to] prove that we didn’t have a pigmentation problem,” BodiMetrics founder and chief operating officer Neil Friedman said. “But that was our goal … to make sure that people had a device that properly measured their blood oximetry and prevented them from being misdiagnosed or potentially dying.”

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Video: NASA Announces Artemis III Crew

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Video: NASA Announces Artemis III Crew

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NASA Announces Artemis III Crew

NASA announced the crew of Artemis III mission, which will fly to low-Earth orbit to test rendezvous and docking maneuvers with one or two lunar landers.

“I am excited to welcome you as the next crew in the Artemis journey to successfully return to the moon — this time to stay.” “I’m honored by the role that I’ve been given. I’m also very humbled by the task in front of us. But first and foremost, I’m grateful.” “So with that, the Artemis II crew, comrade, hands you the baton. You got the controls.” “As you know, we had a significant anomaly at our Launch Complex 36A on May 28. We’ve redoubled our efforts and are moving forward.”

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NASA announced the crew of Artemis III mission, which will fly to low-Earth orbit to test rendezvous and docking maneuvers with one or two lunar landers.

By Alisa Shodiyev Kaff

June 9, 2026

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Santa Monica Mountains’ last steelhead trout survived the Palisades fire — and even had babies

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Santa Monica Mountains’ last steelhead trout survived the Palisades fire — and even had babies

Scientists feared the Santa Monica Mountains’ last remaining steelhead trout were dead, smothered by debris flows unleashed by the Palisades fire.

But the endangered fish surprised them: A team of biologists recently spotted 30 of the rare trout — and 21 babies — in Topanga Creek.

“There was a lot of happy dancing in the creek,” said Rosi Dagit, principal conservation biologist for the Resource Conservation District of the Santa Monica Mountains, which works with public and private landowners to conserve natural resources.

That’s because the steelhead here are endangered, at both the state and federal levels. Once, they swam in most streams of the Santa Monicas, but their numbers plummeted amid overfishing and coastal development. Increasingly frequent wildfire has further stressed their habitat. Topanga Creek, a biodiversity hot spot, is home to their last known population in the mountains that stretch from the Hollywood Hills to Point Mugu in Ventura County.

The trout that were spotted, including this one, are part of a distinct Southern California population that’s listed as endangered at the state and federal levels.

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(RCDSMM Stream Team)

The California Department of Fish and Wildlife spearheaded a complex mission to rescue trout threatened by the Palisades fire that sparked in January 2025.

Time was of the essence. The fire hadn’t yet been fully contained. But rain was on the way, which would sweep massive amounts of sediment from the denuded hillsides into the water. Fish are often killed this way.

Crews stunned the fish with electricity, scooped them up in buckets, trucked them to a hatchery and ultimately moved them to Arroyo Hondo Creek in Santa Barbara County.

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Within days, Topanga Creek was choked with mud. Some assumed the fish left behind were goners.

But in March, the conservation district’s team found four. The following month, when water conditions were clearer, they saw more.

“These fish continue to amaze me,” said Kyle Evans, environmental program manager for the state Department of Fish and Wildlife, who had seen the damage to the creek. “I had seen populations get wiped out in similar situations. So when I heard, I was thrilled.”

Evans surmises the fish that survived were in an area of the creek where less charred material and sediment were swept in.

“These fish likely hunkered down, were hiding under some rocks or places to try to get away from the main concentration of flow,” he said. “And luckily they weren’t buried.”

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The ones that were spotted were fairly small, around 6 to 14 inches. Rainbow trout and steelhead trout are the same species, but with different lifestyles. If the fish remain in freshwater, they’ll be considered rainbows. However, they can migrate to the ocean and become steelhead, where they typically grow larger before returning to their natal waters to spawn.

Topanga Creek hasn’t fully recovered from the damage it sustained, but scientists say it’s looking better. Surveys last year were “so depressing,” Dagit said, with very few animals, and stretches that were essentially transformed into flat roads from all the sediment buildup. Some of the riparian canopy burned right down to the creek.

Then came 32 inches of rain over the last nine months, scouring out and moving sediment, creating deeper pools. Dagit said they recently found newt egg masses for the first time in years, as well as a few adult newts and many frogs. Plants that provide cover are starting to recover.

She provided photos comparing certain pools last year and this year, some dramatically transformed. In September 2025, the Shrine Pool could have been an overgrown hiking trail. This April, it was filled with shallow water.

Shrine Pool, Sept. 2025, left, and the same location, April 2026, right.

The Shrine Pool in September 2025, left, and the same location in April 2026, right, with RCDSMM’s Isaac Yelchin donning a wetsuit.

(RCDSMM Stream Team)

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Topanga Creek is home to another endangered fish, the small but hardy northern tidewater goby, often described as cute. Not long before the trout operation, Dagit led a rescue of hundreds of these fish too. Many were repatriated to the lagoon at the mouth of the creek in a moving ceremony last June.

There’s still the matter of what to do with the trout that were moved to Santa Barbara County last year. Evans would like to bring them home to the Santa Monicas at some point, but isn’t sure if it will happen. On one hand, they could bolster the small, genetically isolated surviving population. On the other, they might inadvertently bring in a disease or bacteria. There is some time to decide. Evans estimates the creek still needs to recover for two to three more years.

For now, the fish are functioning fine in their adopted creek. Experts worried the trauma wrought by the move would disrupt their spawning process, but they had babies that spring. This year, they spawned again.

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Pacifica pier cracks, another coastal casualty as seas continue to rise

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Pacifica pier cracks, another coastal casualty as seas continue to rise

The Pacifica Municipal Pier was shut down and taped off Thursday after city workers noticed cracks running through the landmark structure and concrete chunks falling into the ocean.

It’s just one of many coastal California structures that have recently crumbled under pressure from a rising and relentless ocean.

Officials from the small, beach city south of San Francisco said the pier was closed due to “cracking, separation, and displacement of the concrete walkway and structural elements.”

It will stay closed while structural engineers asses its safety.

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Photos taken by city employees show a wide crack that runs from top to bottom and across the structure as well. Other photos show a large horizontal crack under the foundation of a small restaurant on the pier, the Chit Chat Cafe.

The cafe was also shut down.

This is not the first time the 53-year-old pier has shown signs of stress. In 2021, part of it was shut down after handrails along the edge collapsed. And in 2023, after a series of storms pummeled the Central California coast, damaging parts of the pier, the structure was partially closed for more than year.

Those same storms caused extensive damage in Aptos and Capitola, 70 miles south, where piers and waterfront infrastructure were swept away or damaged.

In 2024, a 150- to 180- foot section of the Santa Cruz wharf was ripped off by powerful waves.

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At least 10 of the state’s dozens of coastal public piers were closed for part or all of 2024 due to structural damage sustained in winter storms since 2022. At least five others have longer-term upgrades planned to address structural issues.

“These things are costly to maintain,” said Zach Plopper, senior environmental director at Surfrider. “They are a part of our California coastal culture in many ways, but we’re going to need to reckon with, one, the state that they’re in, and two, the continuous and worsening threats they’re going to experience,”

He said most of the piers were constructed in the early 1900s, and they weren’t built to withstand decades of rough seas, storms and rising sea level.

“With this incoming El Niño, which is forecasted to be significant, and this marine heat wave we’re in the midst of, we’re kind of in uncharted waters as far as what this winter could bring in terms of storms and swells to the California coast, and we’re likely going to see a lot more damage,” he said. “Not just piers, but roads and other coastal infrastructure up and down the state.”

There was no storm in Pacifica earlier this week, so no single event could be blamed for the destruction.

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However, a 2025 report from an outside engineering firm, GHD, found that several sections of the pier were in “poor” or “serious” condition, and they recommended closure before anticipated storms or events that could “subject the piles to high winds, swells and large waves.”

The firm found several areas of the pier where concrete was missing and rebar was exposed and corroding.

“The pier has continued to experience high winds and large waves in a harsh marine environment,” the engineers wrote in the report, noting that continuous exposure to seawater or marine spray was “detrimental” to the structure.

A 2023 city report estimated it would cost $19 million to repair.

That same year, a state law was enacted to require local governments along the California coast to plan for sea level rise in the coming decades.

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Sea level has risen some 8 inches, on average, along the coast in the past 150 years, Plopper said, and researchers anticipate another foot in the next 25 years.

“We’re going to see profound shifts on our coastline, none that we have ever experienced before, and building static structures on the coast just doesn’t work all that well,” he said. “We’re going to have to make some really hard decisions.”

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