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The coronavirus has brought a lot of attention to breathing machines known as ventilators. The devices can be lifesaving for some critically ill patients. But as NPR's Jon Hamilton reports, they're no panacea.
JON HAMILTON, BYLINE: The intensive care units at Barnes-Jewish Hospital in St. Louis are filling up with coronavirus patients, and Dr. Tiffany Osborn has been caring for many of those who've been placed on ventilators to keep them alive.
TIFFANY OSBORN: It's very concerning to see how many patients who require ventilation do not make it out of the hospital - how many of them die.
HAMILTON: Osborn is a critical care specialist at Washington University School of Medicine. She says doctors in China and Europe and elsewhere in the U.S. are reporting death rates from about 50% to more than 80%.
OSBORN: We're not sure how much help ventilators are going to be. They may help keep somebody alive in the short term. We're not sure if it's going to help keep someone alive in the long term.
HAMILTON: Patients end up on a ventilator when their lungs can no longer deliver enough oxygen to keep the body going. Osborn says it's an extreme measure.
OSBORN: We give sedation so that the person goes to sleep and then we provide a paralytic that stops their breathing.
HAMILTON: Next, they insert a long plastic tube through the trachea and vocal cords that allows a machine to deliver puffs of highly oxygenated air to the lungs.
OSBORN: The ventilator itself can do damage to the lung tissue based on how much pressure is required to help oxygen get processed by the lungs.
HAMILTON: And Osborn says coronavirus patients often need dangerously high levels of both pressure and oxygen because their lungs have so much inflammation. Also, ventilators create a path for a wide range of infections to reach the lungs. Dr. Negin Hajizadeh is a pulmonary critical care doctor at Hofstra/Northwell School of Medicine in New York. She says ventilators work really well for patients with common forms of pneumonia.
NEGIN HAJIZADEH: We treat patients for several days. And then we get the antibiotics into the body, and the patient recovers. Unfortunately with this COVID-associated pneumonia, there are no treatments that we know work for sure.
HAMILTON: So Hajizadeh, who spoke to me from just outside of an intensive care unit, says ventilators are of limited value.
HAJIZADEH: We have had several patients between the hospitals across the Northwell health system that have come off of the breathing machine, but the vast majority are unable to.
HAMILTON: Hajizadeh says one reason is that the coronavirus often does a lot more lung damage than, say, the flu.
HAJIZADEH: There is fluid and other toxic chemical cytokines, we call them, raging throughout the lung tissue.
HAMILTON: She says in some patients, the damage is so bad that even ventilation won't help. So they've tried an even more extreme measure called ECMO which delivers oxygen directly to a patient's bloodstream.
HAJIZADEH: Remember; ECMO, too, is a life-supporting treatment, so it's a bridge while we are allowing the lung to heal itself from a pneumonia.
HAMILTON: If it can - Dr. Tiffany Osborn says that what doctors are learning about severe coronavirus infections should make it crystal clear why we all need to take steps to keep the virus from spreading.
OSBORN: I know that, at times, it gets frustrating. But it's really important not just for yourself and your family but for the - the other people that you care about to shelter in place until this is over.
HAMILTON: Osborn should know. When she's not at the hospital, she's living in a camper to avoid putting her family at risk.
Jon Hamilton, NPR News.
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