JACKSON, Miss. — As states across the country beg for ventilators to help patients suffering with respiratory issues from COVID-19, the University of Mississippi Medical Center is building its own makeshift ventilators with supplies found at a hardware store.

Dr. Charles Robertson, a UMMC pediatric anesthesiologist and the mastermind behind the idea, said he set out to make the "absolute simplest ventilator we can build with parts available in any city; you don't need special tools to put together and can be done quickly as the need arises."

Made with "primarily a garden hose, a lamp timer and electronic valve," the ventilator, named the Robertson Ventilator, for less than $100, can be assembled in approximately 20 to 30 minutes, meaning a dedicated team of four to five could produce nearly 100 in a day if needed, he said.

Demonstrating the functionality of the machine at a news conference Tuesday afternoon, Robertson turned on a ventilator hooked up to a mannequin. The mannequin's chest began to rise and fall.

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"The brain behind the thing is actually a lamp timer," he said. "It's not fancy, but it works. This would be available as a last resort if the numbers increase as we think they might."

While in-demand ventilators may go to states that are the highest bidder, Robertson noted the parts he gathered are from Home Depot and Lowe's.

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"No one has been competing with me for those," he said.

As of Tuesday, UMMC staff had assembled 170 of the ventilators, Robertson said, doubling the hospital's capacity. They have parts to make 75 more.

Given the supplies involved and their wide availability, UMMC has "the ability to quickly manufacture any more if we need them," he said.

Dr. Richard Summers, associate vice chancellor for research for UMMC, addressed the shortage of conventional ventilators, saying, "as a contingency plan, we were looking for our state to be independent."

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The Robertson Ventilators have been tested and proven to be successful on both laboratory animals at UMMC and in simulation, Summers said, and "performed well, even in conditions that we would expect with COVID lung."

The hospital has applied for an emergency use authorization from the Food and Drug Administration for the Robertson Ventilators, in the event the conventional ventilators are already in use.

Dr. Alan Jones, chairman of emergency medicine, said UMMC currently has 80 to 90 conventional ventilators. As of Tuesday, almost 20 patients with COVID-19 and another 20 to 30 non-COVID patients are are on those ventilators.

"I do feel as though we are positioned ... that if we got to the point of needing this it's going to be a dire situation," he said.

Roberston said that if hospitals have the option, a commercially available ventilator should be used first, "but with a patient who's likely to die soon, this could be lifesaving."

"The role of this ventilator is if there's nothing else available," he said. "This is something that can be made quickly.

"The problems with the worst-case scenario is, it will only come on very rapidly and apparent within a day or two that it's going to happen. We can build as many of these as patients to use them."

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