Can Pulse Oximeters Help Monitor COVID Recovery At Home? Science Still Says 'Maybe'

Fact checked on May 20, 2022 by Vivianna Shields, a journalist and fact-checker with experience in health and wellness publishing.

Pre-COVID pandemic, pulse oximeters—small devices that measure oxygen levels in your blood—were the farthest thing from a hot commodity. But once the virus started making its rounds, sales of the tools spiked.

Still, more than two full years into the COVID-19 pandemic, science can't seem to agree on whether or not the devices are truly helpful for people at home recovering from the illness. The conflicting views are shown in two recent research articles—both that examined the effectiveness of pulse oximeters for monitoring recovering COVID patients at home—that came to slightly different conclusions.

The first, a study published in the New England Journal of Medicine, concluded that the addition of home pulse oximetry was no more effective than text check-ins from hospital staff in keeping patients alive and out of the hospital again.

However, another piece of research—this one, a viewpoint published in JAMA—found the opposite: That remote monitoring using pulse oximeters was highly effective at keeping patients out of the hospital during their recovery from COVID-19.

While the two studies came to roughly the same conclusion about how remote monitoring of some kind can help save lives and keep patients out of the hospital after a bout of COVID-19, the conflicting views on pulse oximeters might make you wonder: Are the devices helpful or not to have on hand? Here's what to know.

How Pulse Oximeters Work

A pulse oximeter, sometimes known as a pulse ox, is an electronic device that measures the amount of oxygen you have circulating in your blood. Though it's usually attached to the tip of the finger, pulse oximeters can also be attached to the forehead, nose, foot, ears, or toes.

In a matter of seconds, the device can give a heart rate and oxygen saturation reading (SpO2). There are a handful of things that can affect a pulse oximetry reading, including poor circulation, skin pigmentation or thickness, skin temperature, tobacco use, and fingernail polish.

In most healthy individuals, oxygen saturation levels range from 95%–100%. If you're using an at-home pulse oximeter and your oxygen saturation levels drop below 92% you should contact a health care provider; if it drops below 88%, seek emergency medical attention.

Home Monitoring Via Text Message vs. Pulse Oximeter

For the first study, a randomized trial known as COVID Watch, more than 2,000 participants were assigned to monitor oxygen levels through a pulse oximeter or automated text messages twice a day to self-assess their breathing.

"They were asked two questions," study co-author Anna Morgan, MD, MSc, MSHP, assistant clinical professor at the University of Pennsylvania Perelman School of Medicine, told Health. Participants were asked how they felt compared to 12 hours ago, and depending on the answer, if it was harder than usual for them to breathe. If the patient responded "yes," then a team of clinicians were alerted and the patient was contacted to determine whether they needed to visit the hospital. "They were questions that we felt were very answerable," Dr. Morgan added.

Ultimately, researchers found that patients who received text messages were no worse off than those who used a pulse oximeter. Dr. Morgan added that even anxiety levels among the texting group were roughly the same as those who used the tool.

"There was an expectation of anxiety benefits—that patients would be less anxious if they had a pulse oximeter," Dr. Morgan said. "That really didn't pan out. The levels of anxiety that patients reported were the same."

Meanwhile, the viewpoint published in JAMA found pulse oximeters to be helpful in preventing death in discharged COVID-19 patients, particularly when dealing with a condition known as 'happy' or silent hypoxia, or having low oxygen levels without respiratory distress. Hypoxia, though deadly, can be reversed if caught in time.

Pulse oximeters would be especially useful in those situations since text message monitoring wouldn't reveal a condition for which a patient isn't feeling symptoms, according to viewpoint co-author Peter Pronovost, MD, PhD, FCCM, chief quality and clinical transformation officer at University Hospitals. With pulse oximeters, when oxygen saturation changes significantly or drops below a certain level, hospital staff, theoretically, could be alerted to patients more quickly than through periodic checks.

Remote Monitoring in Any Form Saves Costs and Lives

Although the different points of research may seem at odds with their verdict about the need for pulse oximeters, they agree on the efficacy of remote monitoring of patients. The ability to monitor patients at home can save thousands in medical bills while utilizing readily available tools to hospital systems. Remote monitoring could also help regulate the number of open hospital beds at high volume times.

"We believe that somewhere between 30%–40%, maybe even 50% of hospital admissions can be cared for at home," Dr. Pronovost said. "It's transformative technology. Not only do we have monitoring, but we have an amazing amount of therapies that we can offer at home."

Pronovost says that while his study looked at COVID-19 patients, the technology and monitoring protocols could be applied to several different conditions, including pneumonia, heart failure, and chronic obstructive pulmonary disease (COPD).

Dr. Morgan also said she believes that remote monitoring via text messaging provides new opportunities for at-home care.

"I think the possibilities are endless. I think it's something that all patients can access equally," Dr. Morgan said. "I think that these text message programs are about meeting patients where they are and developing a relationship with them. People like using text messaging, and this is another way we can connect with our patients."

Do You Need a Pulse Oximeter?

The answer here is murky. Pulse oximeters may only give a partial picture when used without the insight of a medical professional.

According to Dr. Pronovost, the quality of the data from consumer-oriented pulse oximeters can be unreliable—many commercially-available pulse oximeters are unregulated as medical devices, and so their accuracy can be unreliable. (Both research articles above used hospital-grade pulse oximeters that can transmit data to trained professionals). It should also be noted too that some studies have shown pulse oximeters to be less accurate on darker skin tones.

That said, there are still accurate pulse oximeters on the market and readily available. Looking for devices that are FDA-approved are a good starting point, Dr. Pronovost said. However, if you have been diagnosed with a heart issue or pulmonary issue, a hospital-grade pulse oximeter may be a good investment, Dr. Pronovost said.

If you're not up for investing in any kind of pulse oximeter, you can still monitor your health at home—specifically by observing your breathing if you have or have recently had COVID-19. If at any point it feels more difficult to breathe than usual, or if your breathing changes suddenly, it's important to contact a health care provider.

Overall, continuous monitoring of any kind and ongoing communication with a health care provider can help you stay out of the hospital in the long term.

The information in this story is accurate as of press time. However, as the situation surrounding COVID-19 continues to evolve, it's possible that some data have changed since publication. While Health is trying to keep our stories as up-to-date as possible, we also encourage readers to stay informed on news and recommendations for their own communities by using the CDC, WHO, and their local public health department as resources.