Completely confused doctors: How is it possible that some coronavirus patients do not feel alarmingly low levels of oxygen?

“There is a discrepancy between what we see on the monitor and the appearance of the patient in front of us,” said Reuben Streyer, an emergency room physician at Maimonides Medical Center in New York, who first encountered unusual cases of hypoxia in March. “.

Dr. Streyer and other doctors want to understand this hypoxia so they know they are treating it.

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Normal oxygen saturation is at least 95 percent. In most lung diseases, including pneumonia, saturation decreases and is accompanied by other changes, such as fluid in the lungs or increased carbon dioxide, as it cannot be expelled by the lungs.

Exactly these changes leave us breathless, says University of Florida respiratory physiologist Paul Davenport:

“The brain is tuned to monitor different carbon dioxide sensors. We don’t feel the oxygen levels.”

In severe cases of KOVID-19, there is a fight for breathing, but in the early stages of the disease, low oxygen saturation is not always associated with obvious respiratory problems.

Carbon dioxide levels can be normal and breathing can be smooth, according to Elnara Marsia Negri, a pulmonologist at the Sírio-Libanês Hospital in Sao Paulo. And that the oxygen saturation is 70, 60, 50 and even lower. This is, after all, a warning, as Dr. Nicholas Kaputo of the New York City emergency room said.

Scientists are now looking for the answer to why low blood oxygen levels occur, and Dr. Negri explained that this may be related to clotting that starts early in the lungs, perhaps due to inflammation of the vessels. that triggers a protein cascade that then causes clotting and prevents the blood from supplying enough oxygen.

Negri developed this idea while treating a woman who had difficulty breathing and poor circulation in her toes. After taking a blood clot, both problems resolved.

The drug was then administered to 27 patients with KOVID-19. One died after being transferred to another hospital, 24 of them recovered, including six of eight patients who were on respirators. Two are in critical condition. Negri plans to administer the drug to other patients, and clinical trials of its use and effectiveness are underway.

Streyer agrees that hypoxia is caused by clots in the small blood vessels in the lungs, but he noted that in some patients an almost waxy content was observed on all sides around the lungs, so he doesn’t know what really it’s happening.

Kaputo added that hypoxia stresses a body that is already struggling with KOVID-19 and that the doctors of these patients should avoid aggressive treatment.

Luciano Gatinoni, a visiting professor of intensive care at the University of Gottingen, said that doctors should not put hypoxia patients on their respirators if they can breathe easily. It can damage the lungs, he wrote April 24 in “JAMA.” This form of treatment should only be applied when non-invasive methods do not produce results.

Streyer, Caputo, and their associate Richard Levitan, a physician at Littleton Regional Healthcare in New Hampshire who treated patients with KOVID-19 in New York, said that simpler approaches like giving oxygen and turning on the stomach could help, this has had an effect on Most of the 50 patients, but 13 were intubated within 24 hours.

The problem is that a large number of people, fearful of the condition in the hospital, are late for help, so doctors wonder if monitoring blood oxygen at home could be helpful.