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UArizona’s Slepian designs three low-cost ventilators ­— one using basketball

Marvin Slepian, M.D.

renowned researcher at the University of Arizona Health Sciences has taken the university’s reputation as a basketball powerhouse to a new level — designing an easily manufactured and low-cost ventilator prototype that uses a basketball to respond to the fast-spreading COVID-19 pandemic.

“We are in a period where ventilators are like gold, and the nation anticipates a widespread lack of ventilators to support critical-care requirements across the nation and world,” says Marvin J. Slepian, M.D., Regents Professor at the UArizona Health Sciences. He is the director of the UArizona Center for Accelerated Biomedical Innovation and leader of an international team that recently submitted three ventilator prototypes for funding by the U.S. Department of Defense.

Slepian’s team submitted a proposal, “PneumEase — Effective Economical Readily Deployable Ventilator Systems,” to the DOD’s Vulcan Challenge, an open call for innovative capabilities that address the challenges presented by COVID-19, and its impacts on public safety and national security processes, systems, and resources.

For the challenge, completed by a public-private partnership including experts at the UArizona and collaborators at major international corporations from a range of industries, “we focused on simple designs that work, without advanced bells and whistles,” Slepian says.

The team was required to submit designs that cost $300 or less, says Slepian, who also is a professor of medicine, medical imaging, biomedical engineering (associate department head), material sciences, and engineering; a member of the UArizona Sarver Heart Center and BIO5 Institute; and a McGuire Scholar in the Eller College of Management.

“Today, ventilators largely are designed like Tesla automobiles, fully electronic, computerized with multiple controls, sensors, and connectivity,” Slepian says. “We don’t need such a sophisticated design in light of the urgency created by this pandemic; we need to go back to simple, basic — but extremely effective — designs,” he adds.

“To address this challenge, we proposed a system that can provide two modes of ventilation — pressure-supported breaths for patients able to breathe spontaneously; and controlled-pressure ventilation, with set maximum volume, for those unable to breathe spontaneously,” he outlines in the application.

The three designs are a Foot Pump Design — based upon use of an inexpensive, readily available pneumatic foot pump; a Sports Ball Design ­— using commonly available sports balls (basketballs, footballs, soccer balls); and a Printed Piston Design — incorporating a sourced piston cylinder or 3-D printed cylinder design. All designs incorporate humidification, temperature control, and filtration of expired air to limit infections and contamination risk. A monitoring-and-control system for all designs will detect if the patient is breathing spontaneously, not breathing autonomously, or breathing autonomously, but below minimum volumes.

How did the team decide upon inflatable balls for one of the designs? “Inflatable balls are enclosed ‘pneumatic chambers’ that are readily available, ruggedly constructed, capable of being pressurized and semi-compliant,” Slepian explains.

Balls may be equipped with simple plastic connectors, from off-shelf rigid plastic tubing or through a 3-D printed “puncture-and-seal connector,” which allows “instrumenting” the ball with an inlet and outlet as a means to allow attachment of gas-flow tubing. The puncture seal connector allows rapid instrumentation and fabrication of the system by minimally skilled workers, while simultaneously offering secure sealing to prevent leaks.

Other design team members include David Hahn, Ph.D., the Craig M. Berge Dean of the UArizona College of Engineering; Monica Kraft, M.D., professor and chair the Department of Medicine at the UArizona College of Medicine–Tucson, deputy director of the UArizona Health Sciences Asthma and Airway Disease Research Center and the Robert and Irene Flinn Endowed Professor of Medicine at the UArizona; Christian Bime, M.D., M.Sc., assistant professor of medicine and clinical translational sciences, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, College of Medicine–Tucson, and medical director, Medical Intensive Care Unit, Banner–University Medical Center Tucson; Sairam Parthasarathy, M.D., professor of medicine and chief, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine. Several ACABI members from private industry also assisted in the fast-paced effort.

UArizona Health Sciences’ COVID-19 Resources webpage is at www.uahs.arizona.edu/node/7358.