Northwestern Medicine Surgeons Develop a Total Artificial Lung System to Keep a Patient Alive for 48 Hours After Removing Both Lungs, Enabling a Double-Lung Transplant

Surgeons and critical care specialists at Northwestern Medicine have successfully supported a critically ill patient for 48 hours after removing both lungs, an extraordinary step taken to eliminate a life-threatening infection and stabilize the patient for a successful double-lung transplant. The case, published today in Cell Press journal Med, describes a “total artificial lung” (TAL) system designed to temporarily replace key functions of the lungs while also helping maintain stable blood flow through the heart and body.

In spring 2023, a Missouri resident was flown to Northwestern Memorial Hospital on extracorporeal membrane oxygenation (ECMO), a form of advanced life support used when the heart and/or lungs cannot provide enough oxygen to the body. What began as influenza-associated lung failure escalated into a rapidly progressive, necrotizing pneumonia and overwhelming sepsis despite maximal therapy. His condition continued to deteriorate, including an episode in which his heart stopped and the team performed CPR.

“He had developed an infection of his lungs that just could not be treated with any antibiotics because it was resistant to everything,” said Ankit Bharat, MD, chief of thoracic surgery and executive director of the Northwestern Medicine Canning Thoracic Institute. “That infection caused his lungs to liquify and then continued to progress to the rest of his body.”

For the sickest acute respiratory distress syndrome (ARDS) patients, clinicians often rely on prolonged life support and time, hoping the lungs can recover. But in some cases, the lungs themselves become the source of relentless infection and inflammation, driving organ failure and leaving no path forward unless the diseased lungs can be removed and replaced. But in these scenarios the patients are also too unstable to go through removal and transplant in the same setting. That created a dilemma: taking out both lungs can stop the infectious source, but without lungs, the body also loses critical gas exchange and the normal circulatory buffering the lungs provide, placing the heart at risk of collapse or catastrophic instability.

To solve this problem, Dr. Bharat’s team designed a total artificial lung system intended to do more than oxygenate blood. The system was engineered to support circulation in the absence of lungs by helping maintain balanced blood flow through the heart, an essential requirement for survival after bilateral pneumonectomy (removal of both lungs). The design incorporated a flow-adaptive shunt that compensated for the loss of the lung’s blood vessel network, dual pathways to drain blood from the body and return oxygenated blood back to the heart.

Because an empty chest cavity can allow the heart to shift, the team used temporary internal supports, including saline-filled tissue expanders (breast implants) commonly used in reconstructive surgery, to help stabilize the heart’s position until transplantation.

“Just one day after we took out the lungs, his body started to get better because the infection was gone,” said Dr. Bharat.

Over the next 48 hours, the patient’s condition improved enough to proceed with transplantation. When donor lungs became available, the Northwestern Medicine team performed a double-lung transplant. More than two years later, the patient has returned to daily life with excellent lung function.

Molecular evidence of irreversible lung injury

Beyond the surgical and critical care advance, this new report includes a detailed molecular analysis of the removed lungs, data that may help physicians better understand when severe viral and infectious lung injury has crossed a threshold from “potentially recoverable” to “irreversible.”

The research team used advanced techniques, such as single-cell and spatial transcriptomic approaches, to study different parts of the removed lungs and discovered extensive scarring and damage caused by the immune system, similar to severe, irreversible lung disease. They found that the cells needed to repair the lungs were almost gone, cells that form scars were everywhere, and the normal structure of the lungs was completely gone. These results explain why just providing support wouldn’t have helped the lungs heal in this situation.

“With severe ARDS, the conventional strategy is to keep supporting the patient and hope the lungs improve,” said Dr. Bharat. “Using our approaches and data, we can show at the molecular level that some patients won’t recover unless they receive a double-lung transplant.”

The Canning Thoracic Institute researchers say these kinds of molecular maps may ultimately support the development of biomarkers and decision tools to identify, earlier and more confidently, when transplantation should be considered, particularly in acute settings where time is limited and patients can deteriorate rapidly.

A highly specialized approach, and a path toward broader options

This strategy requires extensive expertise in transplantation, extracorporeal support, and round-the-clock multidisciplinary critical care. Northwestern Medicine investigators hope the principles described in the study will accelerate the development of more standardized devices and protocols that can safely bridge selected patients to transplant.

“For severe lung damage caused by respiratory infections, even in acute settings, lung transplant can be lifesaving. Patients and families should know to ask about all available options,” said Dr. Bharat.

The pulmonology and lung surgery program at Northwestern Memorial Hospital is proud to be the highest-ranked in Illinois for 14 straight years and No. 7 in the U.S. For more information, visit nm.org/pulmonary.