Governor Andrew Cuomo has warned that New York State is running out of time to get enough ventilators to treat the sickest coronavirus patients. Without them, vastly more New Yorkers could die. But the number of ventilators is not the only bottleneck: hospitals around the country are worried that a surge in COVID-19 patients will catch them short of the staff needed to run the lifesaving machines.

In a typical hospital intensive care unit, one nurse takes care of one or two patients at a time, says Ali Raja, a physician and executive vice chair of emergency medicine at Massachusetts General Hospital. Before an individual is put on a ventilator, an anesthesiologist or emergency room doctor must intubate, or feed a tube down the throat of, that person. Such patients need to be anesthetized and immobilized during this process to avoid feeling like they are choking, Raja says. Then there are the respiratory therapists—roughly one for every 10 patients—needed to set up the ventilators and routinely check in on the machines, responding if there are any alarms or malfunctions. In addition, a critical care doctor must check in on each patient twice a day. There is also the worry that the health care workers themselves will become sick with the virus.

“This disease, unlike really anything we’ve seen in 100 years, doesn’t just affect our patients—it affects our staff,” says Raja, who is estimating that 20 to 25 percent of hospital workers might fall ill and be unable to come to work. Major hospitals such as his have the “bench strength,” or backup staff, to continue functioning with such a reduction, Raja says, but “in community hospitals in Massachusetts, that’s really hard to come by.”

About 80 percent of COVID-19 patients can safely recover at home, studies suggest. Even most of those admitted to a hospital can be treated simply with extra oxygen to help them breathe better, without the need for a ventilator to force air into their lungs. But people whose lungs are filled with fluid need the device to allow their body to focus on fighting the virus rather than struggling to breath, Raja says.

“There are questions about which patients we should intubate and whether we should do it earlier or later in their care. But there’s no doubt that ventilators save patients’ lives,” he says. “While COVID-19 has a mortality rate as high as 50 percent in some ICU case series, it would be much higher if we did not intubate those patients who are severely ill.”

Coronavirus patients who are sick enough to require a ventilator need one for an average of nearly three weeks, whereas a few days are sufficient for many people with other conditions, says Eric Schneider, senior vice president for policy and research at the Commonwealth Fund, a private nonprofit organization that promotes a high-performing health care system. This long-term need means that New York may not—as Governor Cuomo has suggested—be able to free up enough ventilators to send to the next national hotspot, Schneider says.

Hospitals and health care workers are beginning to figure out how to treat two patients at a time on one ventilator. In many places, including Raja’s hospital, experts are working to develop ways to double ventilator capacity while still allowing the different adjustments that each patient might need, he says. The same number of nurses would still be required, Raja says, because “there is so much to nursing care beyond ventilator management. Having two patients on one vent doesn't take anything off of their plate.”

Such doubling up is necessary because of a lack of ventilators and the skyrocketing cost of a new one—from about $25,000 before the current outbreak to $50,000 or more now, Schneider says. “States are bidding against the federal government and against each other,” he says, noting that production cannot ramp up fast enough to meet the current demand. “Prices are all over the place.” Without adequate staff, patients cannot be treated safely even if there are enough machines to go around, Schneider and Raja say.

William Padula’s research at the University of Southern California helps support this observation. Padula, an assistant professor of pharmaceutical and health economics, has been studying the global death rates for COVID-19 and has found they are lower in countries that have more nurses per patient. Nations with one extra nurse per 1,000 people save two lives per million coronavirus patients, according to research he conducted with his colleagues at Johns Hopkins University. “You need skilled specialists available in hospitallike settings to manage patient caseloads and, especially, to deal with high-needs patients on respirators or [others] who need special care,” says Padula, who is now expanding his analysis to include doctors.

Peter Marshall, vice chief for medical critical care at the University of Southern California’s Keck School of Medicine, says his hospital is managing fine—at the moment. But he is anxious for the future. Without an emergency room, Keck usually receives patients who are transferred from other hospitals—often the sickest individuals. Right now, Marshall says, his hospital has 15 patients on ventilators and the capacity to handle at least 30. “If this goes on for weeks and weeks, it’s conceivable that we would have shortages,” he says, adding that other Los Angeles hospitals are already nearing capacity.

Raja says the Massachusetts General Hospital system—one of the largest and best-resourced in the country—should be able to handle all but the most extreme level of demand. Partners Healthcare, the nonprofit parent company of Mass General and other Harvard University–affiliated hospitals, has many nurses and anesthetists who have been working in operating rooms but whose duties can be shifted to care for COVID-19 patients. “We have lots of people with the right expertise,” he says. “What I worry about is smaller hospitals that don’t have the bench strength we do.”

There have been concerns about nurses and other health care workers contracting COVID-19 when they are intubating patients, because the process can generate aerosols that may spread the virus. But Raja says it can be done safely with the proper protective equipment. He says a device called a video laryngoscope allows clinicians to stand a few feet from people, rather than directly above them, while intubating those individuals. Intubation takes only about five minutes, in addition to another 15 to 20 for staff to put on appropriate protective gear, he says.

Major hospitals such as Raja’s have disposable tips for their video laryngoscopes, allowing them to be quickly cleaned. In a smaller hospital, the cleaning process alone might take an hour or more, he says. If the staff have to perform back-to-back intubations, they are going to run out of devices and personnel pretty quickly, he adds.

The real fear, Raja says, is the surge that everyone knows is coming in the next two weeks. “We are all expecting a surge [higher] than anything we’ve seen,” he says. “We have plans ready with more beds and more personnel. But we don’t know whether or not those are enough. There are so many different eventualities we might not be ready for, and we just can’t know, until it starts, whether we are.”

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