Should You Buy a Pulse Oximeter? A COVID-19 Question

During the first major wave of COVID-19 cases in New York City, emergency room physician Richard Levitan noticed something very strange: Pneumonia caused by COVID-19 was being discovered by chance in patients who had gone to the ER for other reasons, ranging from a fall to a stabbing. Although the patients had dangerously low levels of oxygen in their blood — some requiring the insertion of breathing tubes — most of them didn’t appear to have any difficulty breathing. Normally in such cases, patients are in severe distress, struggling for every breath, sometimes even unconscious due to lack of oxygen.

In a recent New York Times article, Dr. Levitan explained that COVID-19 pneumonia is different from other types of pneumonia because it creeps up without the usual warning signs. By the time patients experience shortness of breath, often they’re in very serious trouble. He suggests preventing that outcome by using a pulse oximeter as “an early warning system.”

What is a pulse oximeter? Your healthcare provider may have clipped this little device onto the end of your finger when you visited the hospital or your doctor’s office. “A pulse oximeter is a monitor that uses different wavelengths of light to determine how much oxygen is saturating the hemoglobin in your blood,” explains Timothy Quinn, MD, Chief, Division of Critical Care at Roswell Park. (Hemoglobin is the protein that carries oxygen throughout your body.) This helps your doctor determine how well your lungs are functioning — and if you develop COVID-19, that information is vital.

The numbers displayed on a pulse oximeter provide additional information to help your doctor determine whether or not you need immediate care. “We like numbers and data,” says Dr. Quinn. “If you say, ‘I have a temperature of X or an oxygen saturation of Y,’  that gives us more information than if you just tell us how you feel.”

Using a pulse oximeter at home “is not a bad idea,” he adds, “but you want to make sure it’s reliable.” Pulse oximeters can be purchased online or at many pharmacies. Be sure to check online reviews of different brands and models, because a 2018 study warns that “most sold in drugstores or on the Internet are specifically labeled ‘not for medical use’ and were not reviewed by the FDA for accuracy.” To check the device for accuracy, Dr. Quinn suggests taking your own reading and then getting a reading from someone else to see whether the numbers are similar.

The devices are offered in a wide range of prices, from as low as $13 to professional models at $1,000 and up. Given the current demand, it may take two weeks or more for you to receive an order placed online.

“They’re extremely easy to use,” Dr. Quinn explains. “You turn it on and put it on your fingertip — any fingertip.” Wearing dark nail polish or artificial nails may skew the results, and the same goes for poor circulation or cold hands. Because the device displays both your pulse rate and your oxygen saturation rate, he cautions that you need to make sure you’re reporting the correct number to your physician.

While some people — including smokers, those who use oxygen at home and others with underlying health issues — may have regular levels between 88-92, Dr. Quinn says a reading of 94-100 is the normal range for most people. If the reading falls below 90, it’s time to alert your healthcare provider.

Your temperature is another important piece of information your doctor will need, which is why Dr. Quinn recommends taking it and recording it on a regular basis if you have been diagnosed with COVID-19. “You should remain very aware of how you’re feeling.”

Monitoring your temperature and oxygen saturation could help alert you to COVID-19 pneumonia early on, when treatment is more likely to be successful, and could keep you  from winding up in the ER. Says Dr. Quinn, “Ideally you want to recover at home and not have to come into the hospital.”