Reconfiguring Sleep Apnea Machines as Ventilators

Reconfiguring Sleep Apnea Machines as Ventilators

At the height of the first wave of COVID-19, it appeared that demand for ventilators would outstrip Mount Sinai Health System's supply within a week. What followed was a race against time.

4 min read

Drew Copeland, RPSGT, was worried. New York City had become the nation’s epicenter of the COVID-19 pandemic, and the reports he was hearing from intensive care units across the Mount Sinai Health System suggested that ventilator usage was averaging 90 percent. Even more disconcerting, all indications suggested demand would eclipse capacity within a week.

“Our administrative and clinical leaders cast a wide net to see if we could purchase or secure more ventilators through philanthropic donations,” says Mr. Copeland, Director of Operations for the Sleep Disorders Program at Mount Sinai. “We got an email from Tesla’s CEO, Elon Musk, asking if we could use 200 bilevel sleep apnea machines. Within 30 minutes, we responded yes.”

What followed was a race against time as Mount Sinai's Division of Pulmonary, Critical Care and Sleep Medicine formed and led a team including anesthesiologists, sleep and critical care specialists, and medical students to see how these machines could be reconfigured as ventilators to safely and effectively meet the needs of critically ill patients who required assisted breathing due to COVID-19-associated acute respiratory distress syndrome.

“Everyone at Mount Sinai identified this as a project with potential utility,” says David Rapoport, MD, Professor of Medicine (Pulmonary, Critical Care, and Sleep Medicine) at the Icahn School of Medicine at Mount Sinai. “Administration opened the doors for us to acquire what we needed, regardless of effort or cost. Postdoctoral students wrote up a user manual and helped with assembly. It was an extraordinary collaboration.”

“We got an email from Tesla’s CEO, Elon Musk, asking if we could use 200 bilevel sleep apnea machines. Within 30 minutes, we responded yes.”

Drew Copeland, RPSGT

Several challenges had to be addressed before the bilevel sleep apnea machines could be deployed for critically ill COVID-19 patients. Because the machines are intended for home use, they deliver air via a porous mask interface, which is less effective than intubation and raises the risk of aerosolization of the virus. The team replaced the mask with a closed circuit that delivers tidal volume via an endotracheal tube and added expiratory filters to prevent the virus from being released into the air.

Other modifications included the addition of a monitor that could be accessed outside a patient’s room, enabling safe adjustment of settings, and the incorporation of an alarm system to alert clinicians to airflow issues. “The high levels of oxygen we needed to deliver to patients caused the machines to shut off during bench testing,” Dr. Rapoport says. “You can imagine how dangerous that would be without any warning. We modified the circuit by adding a T-shaped part at the unit to vent carbon dioxide and allow some intentional leakage, thus raising the level of oxygen that could be delivered to a higher level without an unintended shut-off, and used available electronic parts to build in an alarm.”

Within five days, the team had completed a prototype that was tested in Mount Sinai’s Simulation HELPS Center and then on two intensive care unit patients, one of which was an overnight trial, under an emergency use authorization. Having confirmed that the reconfigured devices worked, medical students began converting the donated sleep apnea machines for possible use, using two floors of the medical school library as a makeshift production facility. “The goal was that, if anyone in intensive care ordered one, it would be delivered in five minutes and they could have a patient on it within 10 minutes,” Dr. Rapoport says. “We also conducted demonstrations with Mount Sinai clinicians who were not part of the project to ensure they were well-versed in using them, if necessary.”

As it turned out, New York City’s efforts to flatten the COVID-19 curve proved effective enough that Mount Sinai was able to meet demand for assisted breathing using its existing and donated ventilators. As the pandemic continued to spread across the nation and the world, however, the focus shifted to making both Mount Sinai’s expertise and its donated bilevel sleep apnea machines available to other hospitals. The protocols and instructions for converting the machines were shared with both the Greater New York Hospital Association and the American Thoracic Society, and Mount Sinai has consulted with and sent bilevel sleep apnea machines to hospitals in South America, Africa, and Asia—an effort facilitated by a subsequent donation of 975 units from Alibaba.

“It was a real thrill to see video and photos of these machines being used on patients,” says Mr. Copeland. “I shared that with the entire team as a reminder that, despite the tragedies we have faced, our ability to collaborate on a common goal can make a huge difference.”

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David Rapoport, MD

David Rapoport, MD

Professor of Medicine (Pulmonary, Critical Care and Sleep Medicine)