Sign up to receive posts from The Exchange
Posted By: Mary Knudtson, DNSc, NP, FAAN
May 12, 2020
Emergency rooms in New York are finding COVID-19 pneumonia in some patients who have no shortness of breath. Clinicians have reported that when they did x-rays or CT scans for other issues, they were finding that even patients without respiratory complaints had COVID-19 pneumonia. They found that COVID-19 pneumonia initially causes a form of oxygen deprivation called "silent hypoxia."
Normally, a patient with pneumonia will develop chest discomfort, pain with breathing, or shortness of breath. The ER physicians found that when COVID-19 pneumonia first strikes, patients don't feel short of breath, even as their oxygen levels fall. By the time they have typical pneumonia symptoms, they have alarmingly low oxygen levels and moderate to severe pneumonia on chest x-ray.
Normal oxygen saturation for most persons at sea level is between 94% and 100%. The majority of COVID-19 pneumonia patients seen in New York ERs had remarkably low oxygen saturations at triage—as low as 50%!
The coronavirus attacks lung cells that make surfactant. Surfactant helps the air sacs in the lungs stay open between breaths and is critical to normal lung function. As the inflammation from COVID-19 pneumonia starts, it causes the air sacs to collapse, and oxygen levels fall. The lungs initially remain compliant, not stiff or filled with fluid. This means patients can still expel carbon dioxide and the patients do not feel short of breath. Patients compensate for the low oxygen in their blood by breathing faster and deeper.
ER clinicians recommend that all patients who have been diagnosed with COVID-19 use a pulse oximeter daily for the first 14 days of the illness to regularly check their oxygen levels. They also recommend that all persons with cough, fatigue, and fever should have pulse oximeter monitoring even if they have not had virus testing, or if they have and their swab test was negative, because the tests are only about 70 percent accurate. By doing this, patients with COVID-19 pneumonia could be identified and treated earlier—before the lung damage is as severe. Their experience suggests by identifying and finding the patients with COVID-19 pneumonia earlier, we might be able to decrease the mortality we are now seeing across the US. Following these guidelines to help identify patients seems like a great idea to me.
- Levitan R. The infection that's silently killing coronavirus patients. www.nytimes.com/2020/04/20/opinion/sunday/coronavirus-testing-pneumonia.html. Accessed May 7, 2020.