What is a pulse oximeter? Should you use the device during the coronavirus pandemic?

Respiratory problems are one of the most common symptoms for the coronavirus. Some people have wondered if using a pulse oximeter to monitor oxygen levels could help detect COVID-19 early on.

The device has been selling out in stores and online during the coronavirus pandemic, news outlets have reported.

Some doctors, however, think it isn’t necessary for most people. Here’s what you should know about the device before using it.

What is a pulse oximeter?

Pulse oximetry measures oxygen levels in blood, according to Johns Hopkins Medicine.

“It is an easy, painless measure of how well oxygen is being sent to parts of your body furthest from your heart, such as the arms and legs,” Johns Hopkins Medicine said.

A pulse oximeter is a “clip-like device” that’s placed on the finger or earlobe that can read the oxygen levels in red blood cells, as well as a person’s heart rate.

How does a pulse oximeter work?

The device uses light to measure how much oxygen is in the blood, and it can help determine whether someone needs extra oxygen, according to Johns Hopkins Medicine.

Using that light, the device is able to measure the percentage of oxygen in red blood cells, according to the American Lung Association.

“The oxygen level may also help to determine if you need to receive supplemental oxygen,” the American Lung Association said. “This saturation number (a good number would be over 90-92%) differs from a value called the pO2 (a good number would be over 60-65) which is measured by obtaining blood from an artery.”

Who needs a pulse oximeter?

Doctors could suggest the use of a pulse oximeter if someone has shortness of breath or known lung or heart conditions, according to the American Lung Association.

The information a pulse oximeter gives can be useful in many different situations, Johns Hopkins Medicine said: During or after surgery, to see if lung medications are working, check a person’s ability to handle increased activity levels, see if a ventilator is needed or check if a person stops breathing during sleep.

It also can help people who have conditions that affect blood oxygen levels — like heart attacks, heart failure, anemia, lung cancer, asthma and pneumonia — monitor their health, according to Johns Hopkins.

Can a pulse oximeter help during coronavirus?

TV host Andy Cohen said owning a pulse oximeter helped him monitor his condition after he tested positive for the virus.

“You could scare yourself and think, ‘Oh my God, my lungs don’t feel right,’ but you could use this pulse oximeter and see, ‘OK, well actually, you’re fine, you’re within the range,’” he said on his show “Radio Andy.” “So that’s my pro-tip, make sure you have Tylenol and a pulse oximeter.”

Doctors are seeing lower blood-oxygen levels in coronavirus patients, according to New York Post.

“We are seeing lower levels in coronavirus patients because the virus impedes their ability to oxygenate the blood,” Dr. Eric Cioe-Peña, director of global health at Northwell Health, told New York Post. “There is fluid, instead of air, in their lungs, and so, when the blood passes through those organs, it doesn’t get oxygen.”

Many doctors, however, say a pulse oximeter isn’t needed for most people, and it could even be a bad idea to use as it could create unnecessary anxiety, ABC News reported.

“Keep in mind a pulse ox is only good if you have the ability to supply supplemental oxygen,” Cioe-Peña told ABC News. “So it is good for triage for those who are medically frail. But it is not a tool for everyone to have at home because, regardless, if the outcome is your oxygen saturation is low, you will need to go to a hospital.”

This story was originally published April 8, 2020 at 5:15 PM with the headline "What is a pulse oximeter? Should you use the device during the coronavirus pandemic?."