Pulse oximeters are in great demand.


A pulse oximeter on a person's index finger.
Sandrine Mulas / Reuters
  1. I hate defending Dr. Oz, but …

  2. Here is the agreement with antibodies and immunity against coronaviruses

  3. I miscarried while we were all in solitary confinement

  4. “I want to be taught. NYC ER Docs explains what’s going on for the rest of us.

Slate makes its coronavirus coverage free for all readers. Subscribe to support our journalism. Start your free trial.

Of all the many things we want right now that we can’t have, I bet maybe the top of the list is: information. There is a huge gap between what we want to know about coronavirus – how long will it last, how to treat it best, how to avoid getting it, what to do if we start to feel sick, when do we know – you to go to the hospital – and what we really know. This lack of information, coupled with a spoonful of fear, makes everything that seems to tell you how to survive the virus extremely attractive.

The New York Times published an opinion piece from a pulmonologist on Monday about what makes the virus so dangerous and what could be done to make it less dangerous. Its author, Richard Levitan, left relative security in New Hampshire to spend 10 days caring for patients at the epicenter of the epidemic in New York and learning what he could do to fight the virus. Meanwhile, his lung specialist brain noticed something strange: many patients with severe cases did not seem as visibly distressed as doctors would expect, even if their lungs were compromised and their decimated oxygen levels.

As Levitan writes:

The vast majority of Covid pneumonia patients I have met have remarkably low oxygen saturation at triage – seemingly incompatible with life – but they used their cell phones while we put them on monitors. Although they were breathing fast, they had relatively minimal apparent distress, despite dangerously low oxygen levels and terrible chest x-ray pneumonia.

Levitan’s play describes the frightening consequences of an oxygen-poor body but not feeling as it is poor in oxygen. He writes that because these patients often feel relatively well, they are not treated soon enough. As a result, their lungs suffer more damage and patients need more invasive and intensive care, often associated with a lower probability of survival. It is a scary thing to learn during a pandemic in which common wisdom has become that anyone can stay at home as long as they can, so as not to overwhelm hospitals. Fortunately, Levitan also has a potential remedy for this problem:

There is a way to identify more patients with Covid pneumonia earlier and treat them more effectively – and that would not require waiting for a coronavirus test in a hospital or doctor’s office. It requires early detection of silent hypoxia using a common medical device that can be purchased without a prescription at most pharmacies: a pulse oximeter.

A pulse oximeter is a small device that, when hung on your finger, can give you a reading of your oxygen level. (For most healthy people, oxygen levels are between 94 and 100 percent when awake, doctors worry when they fall below 90 percent. Levitan writes that in his New York hospital, he treated COVID patients with oxygen levels as low as 50 percent.) Perhaps pulse oximeters were available for purchase without a prescription at most pharmacies when Levitan was writing his article. But since its publication, they have become very hard to find – they were sold in most pharmacies when I checked out Tuesday afternoon, and on Amazon, those that are actually well rated have also been sold. (Those that are not well evaluated are probably not approved by the Food and Drug Administration and, according to this study, are not worth your time.)

Publicizing the usefulness of these devices means that so far they have disappeared from most users grab.

Levitan’s play was not the first time that pulse oximeters have been shown to be useful for people struggling with COVID-19. Jessica Lustig, associate editor of the New York Times Magazine, mentioned the device in her March viral essay on caring for her husband during illness at home. (His was “brought by a friend from the pharmacy on the doctor’s advice.”) After recovering from COVID-19, Andy Cohen de Bravo also recommended them in March, as an essential tool for anyone worried about the virus. And as Quartz reported in early April, interest in oximeters has been high since the first case of coronavirus was reported in the United States in January – demand increased by more than 500% that week.

But Levitan’s play is more direct about their usefulness. He concluded by arguing that anyone with cough and fever – whether tested positive, negative or not at all – should monitor themselves with these devices for two weeks. The recommendation added some flair from a doctor and, more importantly, from a lung specialist. It’s almost crazy, after finishing the song, do not think about getting a pulse oximeter as soon as possible – it seems like these tools could be a shortcut to help us find a better way to sort out our overwhelmed hospitals. And yet, in a cruel twist, Levitan spreading the word about the usefulness of these devices means that so far, they have disappeared from most people.

As someone who has not yet purchased a pulse oximeter myself, I was curious to know how hard I would have to buy one. I was also curious to know what the rush on them could mean. Is this another N95 mask situation, where the public who knows something is supposed to be useful ends up keeping them away from the people who need it most? I emailed Levitan to ask him, and his response was reassuring, “There is no competition between hospitals and home appliances; we use different ones that are much more expensive, plugged into heart monitors, etc. “He wrote to me. His other comments make it clear that his advice is a long-term, not immediate, suggestion:

This pandemic is probably not going to go away this winter… maybe something we’ve been fighting for several years – pulse oximeters should be like a thermometer in your house; valuable information on which you contact your doctor to make a decision about the need for assessment and treatment.

It seems logical to me. In the Levitan’s Times article, it doesn’t pretend to offer specific advice on what to do with the information your oximeter tells you – there’s no reading percentage it offers as the number to which you need to record your alarm, or decide to call your doctor when you wouldn’t have otherwise. This is because doctors have yet to understand this. Which means that even if you have COVID-19 and a pulse oximeter, you should always talk to your doctor about how to use it. In other words, it’s always the doctor, not the pulse oximeter, who will help you get through this.

I also asked Jeremy Faust, an emergency room doctor and contributor to Slate, what he thought of the play and the race on the pulse oximeters. He said:

All medical devices provide information that is not so easy to interpret. I see it every time a family member wants me to look at the results of their routine blood tests. They see all these abnormal and “warning” values, and they are worried. But most of them are meaningless. The same can be said of the devices that measure our physiology. For every dubious story about a smart watch that captures an abnormal heart rate, there are countless false alarms, resulting in unnecessary visits to the doctor’s office and the emergency room.

Pulse oximeters could be a great tool for COVID-19. But only if you have been diagnosed or think you really have it. Even then, a low oxygen reading can be meaningful or meaningless.

In other words, like so many others, the possible role of pulse oximeters is not yet clear – including how exactly doctors can use them to better serve patients, and then how doctors can help people. home to use them. Which means if you have a pulse oximeter, great. If you don’t do it right now, it’s fine: calling your doctor if you’re sick will remain your first line of defense. It seems likely that over the next few years they will become household items. But that doesn’t mean it’s the essential tool that will allow you to get through. It just means that, like everything else, we are still figuring it out.

For more COVID-19 coverage, listen to Wednesday’s What Next.


Please enter your comment!
Please enter your name here