putting coronavirus patients on ventilators could be of little benefit to many and even harmful to some.
What's driving this reassessment is a baffling observation about Covid-19: Many patients have blood oxygen levels so low they should be dead. But they're not gasping for air, their hearts aren't racing, and their brains show no signs of blinking off from lack of oxygen.
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Because U.S. data on treating Covid-19 patients are nearly nonexistent, health care workers are flying blind when it comes to caring for such confounding patients. But anecdotally, Weingart said, "we've had a number of people who improved and got off CPAP or high flow [nasal cannulas] who would have been tubed 100 out of 100 times in the past." What he calls "this knee-jerk response" of putting people on ventilators if their blood oxygen levels remain low with noninvasive devices "is really bad. … I think these patients do much, much worse on the ventilator."
That could be because the ones who get intubated are the sickest, he said, "but that has not been my experience: It makes things worse as a direct result of the intubation." High levels of force and oxygen levels, both in quest of restoring oxygen saturation levels to normal, can injure the lungs. "I would do everything in my power to avoid intubating patients," Weingart said.
One reason Covid-19 patients can have near-hypoxic levels of blood oxygen without the usual gasping and other signs of impairment is that their blood levels of carbon dioxide, which diffuses into air in the lungs and is then exhaled, remain low. That suggests the lungs are still accomplishing the critical job of removing carbon dioxide even if they're struggling to absorb oxygen. That, too, is reminiscent of altitude sickness more than pneumonia.