A new device works like a kidney dialysis machine to remove excess CO2 from the blood to help those with COPD, cystic fibrosis, and other diseases.
Conventional respirators can’t remove the carbon dioxide that builds up in the blood of people with chronic pulmonary diseases, a problem that often proves deadly. That could change with a new device from a pioneering biomedical start-up that works like a kidney dialysis machine to remove excess CO2 from the blood.
“With certain disease states like chronic obstructive pulmonary disease (COPD) or cystic fibrosis, the acute retention of CO2 is what really causes the poor outcomes,” said Jeremy Kimmel, PhD, vice president of new technology at ALung Technologies.
The main function of the lungs is gas exchange, to provide oxygen and remove carbon dioxide from the blood. When high levels of carbon dioxide are elevated in the blood, it can lead to respiratory failure. Symptoms include shortness of breath and cognitive issues.
While clinicians can easily re-oxygenate the blood using an oxygen mask, nasal oxygen, or mechanical ventilation, that extra oxygen will not remove the excess carbon dioxide. Moreover, while mechanical ventilation is considered the standard of care for severe respiratory failure, it carries significant risk, including infections, lung or vocal cord damage, and other serious complications.
“There is a significant need to find a way to safely remove CO2 from the blood and reverse acute respiratory failure beyond ventilation,” Kimmel said. To meet that need, ALung developed the Hemolung RAS, an integrated blood pump and gas exchanger that can provide the equivalent of dialysis for the respiratory system.
“It’s a device that takes the blood out of your body, scrubs the CO2, and puts the blood back in your body,” he said. “It works similarly to kidney dialysis, except instead of doing it for the kidneys, we’re doing it for the lungs.”
The device is made up of three discrete components—a minimally invasive flexible catheter that accesses the blood through the jugular or femoral artery, a specially designed cartridge that acts as both a blood pump and a gas exchanger, and a control module that offers real-time measurement of CO2 removal and blood flow rate. The cartridge’s unique design promotes improved gas-exchange efficiency and reduces the risk of clotting by moving the blood quickly, Kimmel said.
“The fluid dynamics of the device are very complex,” he said. “Blood is a living fluid with cells and platelets that are all doing different things and respond differently to mechanical stimuli. We had to use a lot of computational fluid dynamic simulations to look at how blood is flowing, areas of high shear stresses, areas of stagnation, so we could understand the basic mechanisms of how the device is working and how we can build better prototypes.”
ALung spent the last few years fielding the device in Europe, focusing on demonstrating its efficacy to thought leaders who helped them change the way pulmonologists think about treating respiratory failure.
“This isn’t just a new technology, it’s a new therapy, and that’s a challenge to acceptance,” Kimmel said. “The whole concept of removing carbon dioxide from the blood is not the established standard of care. In the current environment of evidence-based medicine, we need to prove to physicians that our device works better and is safer than what they are used to doing. And that’s why we’ve shifted a lot of our work to the clinical science side rather than the commercialization side.”
Last year, ALung received an investigational device exemption from the Food and Drug Administration and is currently enrolling patients for a clinical study at sites around the United States. Kimmel is optimistic that they can show pulmonologists the value of this new therapy and the device that can implement it.
“We are trying to change the way patients in respiratory failure are treated. For decades, the mechanical ventilator has been the mainstay. And while the ventilator saves peoples’ lives and is a necessary part of intensive care medicine, it has many problems that can make patients worse,” he said. “If we are successful, this may open up a whole new area of medicine that can help failing lungs without needed mechanical support.”
Kayt Sukel is an independent writer who focuses on technology.