Since the onset of the coronavirus epidemic earlier this year, numerous countries have found themselves running short of ventilators. Ventilators, used in hospitals' intensive care units, are crucial to helping those worst affected by the virus to stay alive. They take on some of the work of breathing for COVID-19 patients who find themselves in respiratory failure. However, a number of innovative grassroots initiatives, built in weeks by altruistic engineers with distributed design methodologies and open-source licences, have sprung up to try and solve the shortage.
Meanwhile, regulators have been relaxing some medical device regulations around ventilators, potentially making it easier for the new generation of machines to enter the market. New guidance from the UK's medical devices watchdog, the MRHA, has set out the minimum acceptable standards for 'rapidly manufactured' ventilators, capable of supporting a patient's breathing for anything from a few hours upwards. The FDA, meanwhile, has issued an emergency use authorisation for ventilators and related tech, allowing unapproved kit to be brought quickly into service.
Thanks to a wave of engineering innovation and a more favourable environment to build and test new designs, a huge variety of different projects have sprung up to try and fill the gap. The approaches towards solving the ventilator problem are as diverse as the engineers working on them. Some are seeking to simply create low-cost open-source designs and put them in the public domain for others to build, some are hoping to bring old kit back into service, while others are hoping to repurpose other devices -- including old breast pumps -- into simple ventilators.
One group based in Galway, Ireland has come up with a simple concept: by splitting the output and input to a ventilator, it can supply two patients with oxygen rather than just one, effectively doubling the number of patients a hospital could ventilate without any extra machines.
The VentShare system sees the ventilator's output tube spilt with a Y connector to give two separate supplies, one for each patient. Each supply has its own valve, so anaesthetists can adjust the individual air supply separately. One-way valves, as well as bacterial and viral filters, make sure the oxygen supplies of the patients can't cross contaminate each other. Both oxygen supplies also come with their own individual monitor, giving doctors vital feedback on how each patient is doing.
In order to keep costs low, and build trust among its medical user base, the VentShare system uses no new kit or custom-built parts. The prototype device, which took a matter of weeks to build, was created from "just bits and pieces from [home improvement chain] B&Q to prove out the principles that this can work," Tim Jones, a medical device designer and one of VentShare's project leads, told ZDNet.
The same idea of using only easily accessible kit has been brought over to the finished system, according to Jack Connolly, another medical device designer and VentShare co-lead. "We didn't really want to put ourselves in a position where we were designing and building and shipping new products. What we wanted to do is release a toolkit that would allow clinicians and hospitals to assemble an effective system from parts that they have already in the hospital, or that are already on their suppliers list."
The system is now in the process of being tested in the lab and it may soon be trialled in hospitals. "It's quite possible that [VentShare] will just be going straight into the field. Because it would be a last-chance-saloon kind of thing, if you have to decide to choose one patient [to have a ventilator] or give two patients the chance through a new design, that's when we'd test it for the first time. But that would have to be after rigorous testing in the lab where we're continually getting feedback from clinicians on how comfortable they would be to use the system," Jones said.
The VentShare project is working with hardware companies to build a couple of hundred versions of the monitoring systems that form part of the Ventshare design, and will ship them to those hospitals most in need.
It is ultimately a solution that its creators hope will never need to be used. "It is really a last resort. We hope that sharing ventilators won't be necessary but, if it is, then we want to do everything we can in a short space of time to ensure that it is safe as possible for patients," Jones said.
While VentShare is looking to exploit the ventilators already out there, others projects are trying to create low-cost, low-feature-set machines. Among them are MIT's E-Vent and the University of Michigan's Coventor, both conceived as a way of automating a manual resuscitator known as a bag valve mask or AMBU bag.
Bag valve masks bags are usually hand-squeezed by medics as a short-term way of getting oxygen into a patient who's having trouble breathing. A new crop of designs are aiming to have a machine do the squeezing, potentially greatly extending the time a person could receive ventilation in this way.
The systems are meant to be used "when a hospital has used up all ventilators and the only option is manual bagging a patient. We hope that such systems may serve as bridge devices and help with the triage of available respirators and clinicians trained in respiratory therapy," MIT's E-Vent site says.
Anaesthetist Steve Richardson, the doctor who heads up the Coventor project and a fellow at the University of Minnesota's medical school, told ZDNet that he decided to start work on the machine after the medical school's dean put out a call for proposals to help with the coronavirus crisis -- but the seed of the idea was sown much further back while he was still at medical school. "Someone gave a presentation that talked about pandemic preparedness and the fact that in the state of Minnesota, if we had a severe pandemic, we would not have enough N95 masks or ventilators for our state, so I think that that idea was always in the back of my mind as this approached us."
As an anaesthesiologist, Richardson uses a bag valve mask every day, and anaesthesia machines can be repurposed to serve as ventilators -- ideas that fed into the Coventor's creation. Seven hours after calling up friends in the local medical device industry to discuss his idea of automating ventilation through bag valve masks, the first Coventor prototype was built, and second and third iterations followed days later.
Several prototypes and lab testing later, the Coventor team are already in conversation with potential users in countries across the world, and Boston Scientific is looking to begin fabricating the machines.
Like VentShare, the Coventor is aimed at reliving acute shortages of ventilators, rather than replacing fully-featured machines.
"There have been a number of people who have worked at trying to provide the functionality, to reinvent the wheel if you will, of an ICU ventilator with an AMBU bag and it just is extremely difficult to do, so what we focused on is providing a very simple, easy to understand machine that compresses an AMBU bag, it will give you a reliable volume of air and the ability to change the respiratory rate of the patient," Richardson said.
Unlike in ICU ventilators, where results are viewed on a monitor, Coventor users will need to check the machine's effect on patients by taking and analysing a series of blood samples. It may mean extra work for clinicians, but the Coventor team is clear that the ventilator is meant only to be used in extremis: "for use when no other means of appropriate mechanical ventilation exists in regions that are affected by pandemic conditions, by COVID," Richardson said.
The design for the Coventor and the E-Vent, like many others, has been released under open-source licence, so that companies interested in taking the design into production can do so freely.
Also working with an open-source ethos, but hoping to take things one step further on from automated bag valve mask-ventilation, are a handful of community-built projects working on building entirely new ventilators from the ground up. Project Open Air, OSV, PAPR, and OxyGEN are some of the more established projects, and there are many more well-meaning hobbyists efforts being worked on across the board.
However, some projects are aiming especially high: unlike many of the open-source ventilator projects that have sprung up in the wake of the coronavirus pandemic, RespiraWorks is planning to not only create a low-cost ventilator, it's aiming to build and ship it too, focusing on a more complex designs that could give doctors more detailed feedback on a patient's condition and progress.
After drawing together a team with diverse engineering skills -- from the space, energy, hardware and medical-device industries -- a matter of weeks ago, RespiraWorks is days away from an alpha build and two to three months away from production. While that may potentially be after the peak of the coronavirus outbreak in the US and Europe, there will be other countries with more under-resourced or fragile health systems that are still going to struggling with demand for ventilators, during COVID-19 and beyond.
It's these countries that RespiraWorks is ultimately targeting, where -- pandemic or not -- ventilators are in perilously short supply. RespiraWorks is already in discussion with hardware manufacturers in Guatemala about the production of the device, and the country's health authorities on how the machines could be tested and rolled out. "We know that we're not going to be able to replicate the ventilator functions of $25,000 ventilators with a $500 ventilator. We're hoping to get as close as we can," Ethan Chaleff, executive director of RespiraWorks, told ZDNet.
Many of the current crop of startup and homebrew designs for ventilators and related products may not yield functional designs in time to help with the COVID-19 outbreak, if they ever do.
Indeed, many open-source ventilator projects are still at the beginning of their journey from drawing board to hospital ICU. "The tested and peer-reviewed systems lacked complete documentation and the open systems that were documented were either at the very early stages of design (sometimes without even a prototype) and were essentially only basically tested (if at all)," said Professor Joshua Pearce, head of Michigan Tech's Open Sustainability Technology Lab, in a recent research paper on open-source ventilators.
"There is a large amount of future work needed to move open-source ventilators up to the level considered scientific-grade equipment, and even further work needed to reach medical-grade hardware," he said.
However, enough work has been done to show that there are viable alternatives to traditional ventilators which, with a price tag of tens of thousands of dollars, is out of the price range of many countries and hospitals in desperate need.
"There is clear technical potential for alleviating ventilator shortages during this and future pandemics using open-source ventilator designs that can be rapidly fabricated using distributed manufacturing," Pearce said, noting that work needs to be done on developing policies, regulations and funding mechanisms for the development and testing of open-source ventilators for both the current COVID19 pandemic and for everyday use.
The low-cost, open-source or alternative ventilators movements might not have the huge impact at this point in the current coronavirus crisis, but longer term they may have a far more significant impact by providing vital tools in countries and hospitals that need them now, in the next pandemic and beyond.