A Pulse Oximeter Could Save You from Covid-10; Monitoring the Wrong Symptoms will Kill You

As both public and private researchers and health organizations begin to learn more about COVID-19, respected physicians and researchers are suggesting many patients are focusing on the wrong symptoms, delaying medical attention and ultimately facing the uncertain availability of a ventilator when their lung capacity is exhausted. For nearly two months, patients have been largely instructed to wait at home until their symptoms – cough, fever and body ache, loss of taste or sense of smell, or difficulty breathing – either improve or worsen, but physicians at the heart of the pandemic are treating patients who waited far too long – based on medical advice. 

The human body is a remarkable organism, when one part of the organism cannot function at 100%, the body can compensate for extended periods of time. Such is the case of the novel coronavirus. As the virus attacks the lungs’ function and capacity, the body overcompensates by breathing harder to offset the incapacity. By the time the body is exhausted from compensating, the weakened immune system simply fails, and patients can no longer breathe on their own. There is a light at the end of the tunnel; however, as leading voices begin to advocate for the use of simple, at-home technology to measure lung function using oxygen saturation levels.

Anyone who’s been to the doctor’s office, a clinic or hospital should be familiar with the oximeter – a medical device slightly larger than a clothespin that clips onto the finger to measure pulse and, perhaps provincially, oxygen levels, offering insight into lung function, which can be inhibited by pneumonia.

On Monday, the New York Times published an opinion piece by Dr. Richard Levitan, an emergency physician who worked at Bellevue hospital in New York City for 10 days during the height of the crisis in the city. He cited his experience as a physician, inventor of an imaging system for teaching intubation and his experience in the E.R. in New York City. “I heard from a fellow physician that this [the pandemic] would be like nothing I’d ever seen. He was right,” said Levitan. “Pneumonia caused by the coronavirus had a stunning impact on the city’s hospital system.” During his time at Bellevue, almost all E.R. patients had Covid pneumonia. Within the first hour of his shift, he inserted breathing tubes into two patients.

“Even patients without respiratory complaints had Covid pneumonia. A patient stabbed in the shoulder, whom we X-rayed because we worried he had a collapsed lung, actually had Covid pneumonia. In patients on whom we did CT scans because they were injured in falls, we coincidentally found Covid pneumonia. Elderly patients who had passed out for unknown reasons and a number of diabetic patients were found to have it,” he said.

According to Levitan, these patients did not report any sensation of breathing problems, even though their chest X-rays showed diffuse pneumonia and their oxygen was below normal. “We are just beginning to recognize that Covid pneumonia initially causes a form of oxygen deprivation we call silent hypoxia — silent because of its insidious, hard-to-detect nature,” Levitan said.

Pneumonia is an infection of the lungs in which the air sacs fill with fluid or pus. Typically, patients develop chest discomfort, pain when breathing and other breathing problems. But when Covid pneumonia first strikes, patients do not feel short of breath, even as their oxygen levels fall. And by the time they do, they have alarmingly low oxygen levels and moderate-to-severe pneumonia (as seen on chest X-rays). Normal oxygen saturation for most persons at sea level is 94% to 100 %; Covid pneumonia patients that Levitan saw had oxygen saturations as low as 50%.

Levitan is not the only physician looking at oxygen saturation levels as conversation-starting indicators of the severity of the illness. Dr. Michael Marcin, M.D., M.S.C.R., clinical professor and medical director at University of California San Francisco, noted in his research that there is a national conversation starting across the United States regarding pulse and oxygen levels as a proxy for determining infection. Marcin, in an interview with Polo Lifestyles, suggested that every household purchase an oximeter and regularly check oxygen saturation levels, noting any fluctuations. “Someone asked me a good question,” he said. “Since there is no treatment for Covid, why does it matter if you catch it earlier? For me, there are a lot of ways to support breathing early on that keeps you from needing a ventilator. Conceivably, if you are in a hospital before your lung capacity drops, you can basically fall apart in a situation where everyone is prepared for that possibility. There is support in place at a hospital, whereas at home, you’re falling apart and then rushing off to the hospital at the last minute. A lot of the damage to the lungs comes from our own immune systems. Doctors and nurses can better reduce the impact of your body’s immune response. It’s like the Trust Game (falling into the arms of friends who will catch you): when you allow yourself to fall into the arms of someone prepared, that is very different than when you fall, and no one is prepared or looking after you. Both times you are falling, but you have very different outcomes.”

Marcin believes people are looking for the wrong symptoms before they become patients. Cough, body aches and pains, fever and shortness of breath, none of these symptoms actually tell you when you need hospitalization, he said. “What hospitals across the country are discovering is that patients are showing up too late to get care. How is that? It’s because people are focusing on symptoms that aren’t good markers for severity of illness.” What causes people to die, researchers are saying, is the inability of the lungs to function due to damage from the infection. “Our bodies are compensating for poor lung function for so long that when breathing is difficult and coughing is uncontrollable, it’s already too late. You need to be hospitalized early. You need to seek medical care when you can be saved, not be admitted to the ICU to be hooked up to a ventilator,” he said. 

This revelation comes despite many hospital policies and measures meant to discourage mildly sick people from seeking hospitalization. “I’m sticking my neck out here,” Marcin said. “But I think lung function is a major symptom. The doctors in the E.R. work on concrete facts and figures – give them something concrete to work with: an oxygen saturation number.”

Levitan’s experience backs up Marcin’s research. “A vast majority of Covid pneumonia patients I met had remarkably low oxygen saturations at triage — seemingly incompatible with life. Although breathing fast, they had relatively minimal apparent distress, despite dangerously low oxygen levels and terrible pneumonia on chest X-rays.”

The coronavirus attacks lung cells that make surfactant. This substance helps the air sacs in the lungs stay open between breaths and is critical to normal lung function. As the inflammation from Covid pneumonia starts, it causes air sacs to collapse, and oxygen levels fall. Yet the lungs initially remain compliant, not yet stiff or heavy with fluid. Patients still expel carbon dioxide, and without a buildup of carbon dioxide, patients do not feel short of breath.

This silent hypoxia, and the patient’s physiological response to it, causes more inflammation and more air sacs to collapse, and the pneumonia worsens until oxygen levels plummet. In effect, patients are injuring their lungs by breathing harder and harder. Dr. Luciano Gattinoni, of the Department of Anesthesiology and Intensive Care at the Medical University of Göttingen, found that 20% of Covid pneumonia patients develop a second and deadlier phase of lung injury. Fluid builds up, and the lungs become stiff, carbon dioxide rises and patients develop acute respiratory failure.

By the time patients have noticeable trouble breathing and arrive at the hospital with dangerously low oxygen levels, many will ultimately require a ventilator.

“There is a way we could identify more patients who have Covid pneumonia sooner and treat them more effectively — and it would not require waiting for a coronavirus test at a hospital or doctor’s office,” Levitan told the New York Times. “It requires detecting silent hypoxia early through a common medical device that can be purchased without a prescription at most pharmacies: a pulse oximeter.”

Pulse oximetry is no more complicated than using a thermometer. These small devices turn on with one button and are placed on a fingertip. In a few seconds, two numbers are displayed: oxygen saturation and pulse rate. Pulse oximeters are extremely reliable in detecting oxygenation problems and elevated heart rates.

The New York Times reported that detection of hypoxia, early treatment and close monitoring also worked for Boris Johnson, the British prime minister.

“Widespread pulse oximetry screening for Covid pneumonia — whether people check themselves on home devices or go to clinics or doctors’ offices — could provide an early warning system for the kinds of breathing problems associated with Covid pneumonia,” Levitan said.

According to Marcin, people using the devices at home should consult with their doctors to reduce the number of people who come to the E.R. unnecessarily due to misinterpretation. There also may be some patients who have unrecognized chronic lung problems and have borderline or slightly low oxygen saturations unrelated to the coronavirus.

Levitan concluded his analysis of the pandemic with a call to patients who have tested positive for the coronavirus: “All patients who have tested positive for the coronavirus should have pulse oximetry monitoring for two weeks, the period during which Covid pneumonia typically develops. All persons with cough, fatigue and fevers should also have pulse oximeter monitoring even if they have not had virus testing, or even if their swab test was negative, because those tests are only about 70 percent accurate. A vast majority of Americans who have been exposed to the virus don’t know it.”