by Mark Harris, IEEE Spectrum
Early on in the COVID-19 pandemic, engineers launched extraordinary crash programs that produced scores of ventilator designs. What will happen to them now?
The projections were horrifying. Experts were forecasting upwards of 100 million people in the United States infected with the novel coronavirus, with 2 percent needing intensive care, and half of those requiring the use of medical ventilators.
In early March, it seemed as if the United States might need a million ventilators to cope with COVID-19—six times as many as hospitals had at the time. The federal government launched a crash purchasing program for 200,000 of the complex devices, but they would take months to arrive and cost tens of thousands of dollars each.
Across the United States and around the world, engineers sat up and took notice. At NASA’s Jet Propulsion Laboratory (JPL), in Pasadena, Calif., a chance meeting between engineers at a coffee machine led to a prototype low-cost ventilator in five days. At Virgin Orbit, a rocket startup in nearby Long Beach, engineers assembled their own ultrasimple but functional ventilator in three days.
And in Cleveland, a team at the Dan T. Moore Company, a holding company with an impressive portfolio in industrial R&D, had its first prototype up and running in just 12 hours. “It was made out of plywood and very crude,” says senior engineering manager Ryan Sarkisian. “But it gave us a good understanding of what the next steps would be for a rapid response–style solution.”
From the largest universities to domestic garages, hundreds of teams and even individuals scrambled to build ventilators for the expected onslaught. An evaluation of open-source ventilator projects has tracked 116 efforts globally, and it is far from comprehensive.
Meanwhile, the U.S. Food and Drug Administration (FDA) rushed through rules at the end of March that would allow, if the worst-case scenarios came to pass, new ventilators and other medical devices intended to treat COVID-19 to be deployed without the usual years-long safety assessments. Around the same time, General Electric and Ford announced that they were joining forces to rapidly manufacture 50,000 ventilators based on one of GE’s existing designs.
With hundreds of thousands of traditional ventilators on order and potentially even more DIY devices coming soon, President Trump boasted in a speech on 29 April, “We became the king of ventilators, thousands and thousands of ventilators.”
Now, though, before most of the DIY ventilators could make it to production, let alone treat a patient, the need for them has faded away. Aggressive social distancing and isolation policies have slowed transmission of the coronavirus, while hospitals and state governments readily shared surplus ventilators with locations that were suffering the worst outbreaks, like New York City.
Today, some hospitals are even quieter than they were before COVID-19. “This morning in Cincinnati, there were 12 COVID-19 patients on a ventilator,” said Richard Branson, a professor of surgery emeritus at the University of Cincinnati College of Medicine. In a phone interview with IEEE Spectrum in late April, Branson, who is also editor in chief of the journal Respiratory Care, added “We usually have more patients on ventilators than that on a regular day, but we canceled all the [elective] surgeries.”
No one is complaining about having too many ventilators, of course. The story line, starting with the earnest pleas and the ensuing media frenzy, and continuing with the massive engineering response, certainly has a heartwarming ring. Countless engineers dropped what they were doing and worked long hours to design, build, and test impressive machines in weeks, rather than months or years. But an unforeseen twist in that story line raises some vexing questions. What has become of all these rapid-response ventilator projects and the tens of thousands of home-brewed devices they planned to produce? Has it all been a well-intentioned waste of time and money, a squandering of resources that could have been better put toward producing protective equipment or other materials? And even if any of these devices do find their way into hospitals, for example, in developing countries with a real need for ventilators, will they be safe and effective enough to actually use?
“There was one particular day where I was scrolling through Facebook, and one, two, three friends had lost a friend or family member to COVID-19,” remembers Wallace Santos, cofounder of Maingear, a maker of high-performance gaming computers based in Kenilworth, N.J. “That’s when I thought, Holy crap, this is really happening.”
So when Rahul Sood, the chairman of Maingear’s board and a longtime tech entrepreneur, suggested that Maingear build a ventilator itself, Santos was interested—if skeptical. “I didn’t know if we could do it, but we started to investigate,” he says. “And the truth is that if we can build really complex and beautiful liquid-cooling systems [for computers], we can build a ventilator as well. It’s not that hard actually.”
Like most medical gear, ventilators come in different types and sizes, and with different features, capabilities, and levels of complexity. They all perform the same basic function: getting oxygen into, and in some cases clearing carbon dioxide away from, the lungs of people who are having trouble breathing or who have ceased to be able to breathe at all. In relatively mild cases, physicians may use a noninvasive type, in which a tight-fitting mask, akin to a full-face scuba mask, provides pressurized air to the patient’s nose and mouth.
More severe cases are treated with an invasive system, meaning they make use of a tube through the mouth or through an opening in the neck into the patient’s windpipe (trachea). With this setup, the patient is usually sedated or kept unconscious for the days or weeks it can take for the patient’s body to fight off the infection and regain the ability to breathe independently.
Ventilators must carry out several functions with extreme reliability. They must, of course, supply oxygen at higher-than-ambient pressure and allow carbon dioxide to be exhaled and cleared away from the patient’s lungs. The air they provide to the patient must be warm and moist, and yet free of bacteria and other pathogens. Also, they must be equipped with sensors and software that detect if the breathing mask or tube has been dislodged, if the patient’s breathing has become erratic or weaker, or if the breathing rate has simply changed. Finally, the machines must be designed so that they can be thoroughly cleaned and also contain, as much as possible, any pathogens in the patient’s exhalations. The systems must also be compatible with existing hospital infrastructure and procedures.
Consider Maingear’s design, which was based on an emergency ventilator that had already been used in Italy and Switzerland. To repurpose it for COVID-19, engineers made the part that touches a patient disposable rather than cleanable, to reduce the risk of cross infection. Maingear also rewrote some of its software and designed a tough PC-style case so that it could either be housed in a standard medical equipment rack, or moved about on wheels. “This thing is seven grand out the door,” says Sood. “And we can manufacture them very quickly in New York or New Jersey once we get FDA approval.”
At Dan T. Moore, engineering manager Sarkisian had a similarly abrupt introduction to ventilators. Before working on its ventilator, dubbed SecondBreath, his team had been developing lightweight, high-strength metal matrix composites for automotive brake pads. “We’re fairly green when it comes to medical devices,” he admits. “But understanding that manual resuscitation bags are readily available and already have FDA approval, we wanted to utilize that concept as a way to transfer breath to a patient.”
Just as it sounds, a manual resuscitation bag allows a trained medic to provide ventilation by squeezing on a rubberized bag attached to a face mask. Originally designed in the 1950s, these bags are simple and flexible, but they do require a trained operator. To bring the tactic into the modern age, Dan T. Moore’s engineers focused on automating, controlling, and monitoring that squeezing process.
After building a bag-squeezing prototype in 12 hours, Sarkisian’s team of nine automotive engineers refined the design by talking to local doctors and experimenting with different components. “We were trying to make it as cheap as possible, and to really understand the features that it needs to have to keep people alive,” Sarkisian says.
At a minimum, that meant a system that could reliably squeeze a bag for hours, or even days, on end, be readily usable by doctors accustomed to working with more sophisticated ventilators, and have a suite of alarms should anything go wrong.
“We had about two weeks working through prototypes, adding more alarms and different sensors to optimize our system,” says Sarkisian. “Then a little over a week testing out the system, and another two to three days at a local hospital on lung-simulator machines.” It took just 21 days from the first SecondBreath prototype to submitting the device to the FDA, and the company hopes to sell its devices for around US $6,000.
“It just shows you that medical devices are pretty dang expensive,” says Andrew Dorman, an engineer who worked on the SecondBreath project. “When people learn that we can make these ventilators in three weeks and can sell them for a fraction of the price, they might take a look at [the traditional] medical system and say, something’s wrong here.”
Virgin Orbit also made a bag-squeezing ventilator after its CEO, Dan Hart, offered his factory and workers to California governor Gavin Newsom. Newsom connected Hart to the California Emergency Medical Services Authority (EMSA), which identified ventilators as its key need at the time. “A consortium of physicians, scientists, and engineers led by the University of California, Irvine, and the University of Texas at Austin directed us [to] go and make the simplest possible ventilator,” says Virgin Orbit vice president for special projects Will Pomerantz. “We essentially took all the people who were going to be building next year’s rockets and said, ‘Next year’s rockets can probably wait a little bit—you’re going to be building or testing ventilators.’ ”
As a manufacturer of air-launched rockets for small satellites, Virgin Orbit realized that one of the bigger challenges was going to be dealing with supply chains disrupted by COVID-19 itself. “We tried to build it without requiring anything complex or specialized, or if it was, from an industry that does not touch upon medical devices at all,” says Pomerantz.
For example, instead of building a motor from scratch, the Virgin Orbit team utilized something they could find in almost any small town: the windshield wiper motor from one of the country’s most ubiquitous cars, a 2010 Toyota Camry.
This concern for manufacturability also drove the scientists and engineers at NASA’s JPL. They wanted their ventilator, an open-source design, to be within the reach of almost any competent mechanic, anywhere in the world. “Our target was that if a person had all the parts sitting in front of them, they could put it together alone in about 45 minutes, with as few tools as possible,” says Michael R. Johnson, a spacecraft mechatronics expert who served as chief mechanical engineer for the JPL’s ventilator, called VITAL (Ventilator Intervention Technology Accessible Locally). “We couldn’t make them fast enough. Not that anybody was saying anything—it was just understood.”
In the end, the JPL actually designed two different low-cost, easy-to-assemble ventilators, neither of which relied on existing resuscitation bags. A pneumatic device uses stored energy in the hospital gas supply to power the ventilation, while a design that uses a separate compressor serves situations where pressurized gases are unavailable. Not only would the two designs serve different needs, they would also reduce the chance of component shortages halting production entirely. A single circuit board serves both designs, using a simple microcontroller assembly running Arduino code.
The pneumatic ventilator was ready first and was sent straight to the Icahn School of Medicine at Mount Sinai, in New York City, for testing on human simulator machines and by medical staff. “The whole time it was there, we had a Zoom meeting running, and we were watching them use it,” says Johnson. “We would watch things like how they were pushing the buttons. There was one they were pushing really hard, and I thought, okay, let’s add a couple more support screws to the circuit board. Or we’d hear someone say how it wasn’t adjusting quite the way they’d like, so we made a note to change the sensitivity.”
Beyond the engineering work, preparing the descriptive and safety paperwork required by the FDA involved a significant investment of time and resources. Most efforts used outside lawyers and experts, with the JPL’s comprehensive submission running to 505 pages. “A big thing for the FDA is the failure modes and effects analysis, which we do all the time for our spacecraft,” says Johnson. “We asked a couple of medical companies if they could send us examples, and it turns out they’re actually less rigorous than what we do for our space missions.”
Probably best prepared for the administrative burden of developing a new ventilator in a matter of weeks was the team at the University of Minnesota’s Earl E. Bakken Medical Devices Center. For their day jobs, the engineers here work with industrial partners to come up with ideas for, and develop prototypes of, medical devices.
“We have iterative design processes that I’ve both learned and taught here, so I knew that this was possible if you took the right approach,” says Aaron Tucker, lead engineer for the university’s Coventor ventilator project. “We boiled it down to the key concepts—what you need on a bare minimum to survive when you’re being ventilated.”
The Coventor is another design that compresses commercially available ventilation bags, paring the parts down to just $150 of readily available components housed in plain sheet metal. The Coventor team worked closely with Boston Scientific, a large manufacturer of medical devices, to label their device so as to mitigate the risks around its limited capabilities. “Our experience and our ability to collaborate was why we ended up being [one of the first] approved for use by the FDA,” says Tucker. The Coventor’s selling price will be less than $1,000 when Boston Scientific moves it into production shortly.
By mid-May, the FDA had approved six new ventilators for emergency use, including devices from Coventor, SecondBreath, Virgin Orbit, and the JPL. All are limited to use during the pandemic, and only when standard ventilators are unavailable.
SecondBreath has manufactured 36 devices so far, while Virgin Orbit has produced a couple of hundred. Coventor and Boston Scientific have an order for 3,000 of their ventilators from UnitedHealth Group, a health care company in Minnesota. As of early June, none had been deployed in the United States.
“I don’t think any of these devices will ever be used in the United States,” says Branson, the University of Cincinnati surgery professor. “I give these people a lot of credit. They’re trying to do something positive. They’re very smart, they’re motivated, they’re well meaning, but they don’t know what they don’t know.”
In 2014, Branson coauthored a prescient paper for the journal Chest called “Surge Capacity Logistics: Care of the Critically Ill and Injured During Pandemics and Disasters.” In it, he and 10 colleagues came up with evidence-based recommendations for coping with a pandemic respiratory disease like COVID-19, including stockpiling ventilators that met a list of minimum requirements.
“Several of the ventilators the government is purchasing don’t meet these requirements,” Branson says. “Some barely meet not even half of them.” The ventilators authorized by the FDA for emergency use seem to similarly fall short, often in multiple areas. Branson notes that the bag-squeezing designs, in particular, are problematic.
“If everybody had paralyzed respiratory muscles and normal lungs, as in polio, a bag squeezer would work,” he says. “But this is an acute respiratory distress syndrome with parts of the lung that are stiff right next to parts of the lung that aren’t. If you’re not careful with how you deliver the breath, areas that are stiff get very little gas, and areas that are not get too much gas, and that injures them.”
Another problem is that most of the DIY ventilators do not allow for patients to breathe on their own, requiring them to be heavily sedated. “But in New York City [at the height of the outbreak], they ran out of drugs to sedate people,” Branson notes. “And paralyzing people has its own negative consequences,” he adds. “In general, the less sophisticated the device is, the more sophisticated the caregiver has to be.”
But in the kind of crises where emergency ventilators will be needed, medical staff will already be stretched dangerously thin. Branson believes that asking them to suddenly start using unfamiliar new devices that lack traditional protective features and alarms is a recipe for disaster. “You can’t change the standards of care to meet the requirements of the ventilator,” he says.
With the need for ventilators down sharply in North America, and with many medical professionals there reluctant to use home-brewed ventilators, what will become of all this work? Some DIY ventilator teams are already looking overseas. Indeed, Coventor, SecondBreath, and the JPL all designed their devices with an eye on developing countries. “We know that the ‘Cadillac’ ventilators we’re used to in the U.S. are not available in many countries, for cost and other reasons,” says Coventor’s Tucker. “We’re thinking about whether and how we can start to move the Coventor overseas. Nothing prevents it from being used globally. We even picked a global power supply.”
Virgin Orbit has already found a manufacturer in South Africa to produce at least 1,000 of its resuscitators for use by the African Union.
Whether the U.S. startups can sail past foreign regulators as swiftly as they did the FDA remains to be seen. And there are already plenty of engineers innovating overseas, of course. In India, for example, AgVa Healthcare has been marketing a compact ventilator for less than $3,000 and claims to be building 10,000 units a month.
None of the organizations Spectrum spoke with would put a dollar amount on their DIY ventilator efforts, but the combined total is very likely well into the millions. Branson suggests that some of those funds might have been better deployed in proven technologies. “The answer would be to have money and resources given to people who already make FDA-approved devices, to make more of them,” he says. Other tech companies also focused on much simpler items that are still in short supply, such as protective masks and gloves.
For now, as the adrenaline rush from having produced their first ventilators ebbs, some of the ventilator teams are experiencing a welcome lull. “It did a lot for employee morale to feel like we were all putting our shoulders to it and pushing together,” says Virgin Orbit’s Pomerantz. “If the world needs our ventilators, we’ll keep building them. And if it doesn’t, thank goodness. We’re happy to get back to our day jobs.”
Not everyone is convinced that the worst is over. Sood is keen to keep Maingear’s development effort on track. “Based on everything that we’ve seen and all the data we looked at, this is just wave one of a multiwave process,” he says. “We think that wave two, sometime in the fall, might even be worse, and they’re going to start asking for ventilators again. We want to get our machines prepared and ready ahead of time.”
Sood’s pessimism has plenty of company. When the JPL recently invited firms to ask for (free) licenses to manufacture NASA’s open-source ventilators, it received more than 200 applications from organizations all over the world. The best-case scenario, from all perspectives, is that such efforts continue to be a magnificent waste of time and money.
Read the full article on IEEE Spectrum.
