Artificial lung keeps patient alive after lung removal

By Dr. Priyom Bose, Ph.D.Reviewed by Benedette Cuffari, M.Sc.Feb 5 2026

By replacing both breathing and circulatory buffering, a novel artificial lung bought critical time after lung removal, revealed irreversible damage, and made transplantation possible when no other options remained.

Study: Bridge to transplant using a flow-adaptive extracorporeal total artificial lung system following bilateral pneumonectomy. Image Credit: AbirArt007 / Shutterstock.com

A recent case report published in Med evaluates the effectiveness of a novel extracorporeal total artificial lung (TAL) system to enable bilateral pneumonectomy in a patient with severe acute respiratory distress syndrome (ARDS).

Challenges of treating ARDS patients with respiratory infections

The mortality rate exceeding 80 % of ARDS patients following the development of drug-resistant infections and septic shock underscores the severity of this condition. Lung transplantation is rarely attempted in these cases, as persistent infection could spread to the transplanted lungs, especially when patients receive immunosuppressive drugs.

A major challenge in ARDS is establishing whether lung injury is reversible. Standard diagnostic tools like imaging, physiological tests, and tissue biopsies often cannot determine whether lung damage might heal or is permanent and irreversible.

Although mechanical ventilation and extracorporeal membrane oxygenation (ECMO) can improve oxygen levels and reduce lung trauma, these treatments cannot stabilize the circulatory collapse and hemodynamic instability caused by sepsis. This unstable cardiovascular state is the primary issue that prevents transplantation in patients with infected ARDS.

Removing both lungs in certain patients could eliminate the source of infection before transplantation. Some medical teams have used modified ECMO systems to maintain breathing and heart function after this type of surgery, with early results suggesting that some patients can remain alive until transplant.

However, removing both lungs also removes the blood vessels that normally act as a buffer for blood flow from the right side of the heart. Continuous blood flow to the left side of the heart is essential to maintain proper heart function and prevent blood clots.

Development of an artificial lung system

An extracorporeal total artificial lung (TAL) system was developed to assume gas-exchange and hemodynamic-buffering functions after bilateral pneumonectomy. This system incorporates an adaptive shunt responding to blood flow dynamics and dual left atrial return pathways to maintain physiological circulation and cardiac stability in severely septic patients.

Following lung explantation, tissue samples underwent comprehensive single-cell and spatial molecular profiling to establish definitive evidence of terminal lung injury and characterize molecular pathways driving fibrotic remodeling. Comparative analysis with existing lung injury datasets enabled characterization of the molecular pathways involved in fibrotic remodeling and failed tissue repair.

These analyses were performed to identify biomarkers that differentiate irreversible injury from recoverable damage to potentially enable earlier transplant referral, a crucial consideration given that delayed assessment correlates with elevated mortality.

Assessing the efficacy of the TAL system

A 33-year-old man with influenza B-associated ARDS developed rapidly progressive necrotizing pneumonia from carbapenem-resistant Pseudomonas aeruginosa and bilateral empyemas over six weeks. Despite maximal antimicrobial therapy, source control, and venoarterial ECMO support, the patient experienced recurrent cardiac arrest episodes from refractory septic shock, thus necessitating bilateral pneumonectomy with extensive pleural debridement as salvage source-control therapy to eliminate the infection source and enable possible transplantation.

Following pneumonectomy, extracorporeal support transitioned to the TAL configuration. The dual-lumen Protek-Duo cannula provided robust venous drainage exceeding 4.5 L/min. Moreover, the flow-adaptive shunt provided physiologic autoregulation with conduit flows ranging from 1.1 to 6.3 L/min, thereby preventing acute right ventricular distension in the absence of pulmonary vascular capacitance.

Marked hemodynamic improvement occurred within hours of TAL initiation, with vasopressors discontinued 12 hours post-pneumonectomy. Serum lactate levels normalized from 8.2 mmol/L to below 1.0 mmol/L by 24 hours.

Mixed venous and arterial oxygen saturations exceeded 70 % and 92 %, respectively. Organ function parameters remained stable throughout 48 hours of support, with no evidence of intracardiac thrombus formation despite no systemic anticoagulation.

Bilateral lung transplantation was performed 48 hours after TAL initiation. The patient was extubated seven days later and discharged eight weeks following the transplant.

Primary graft dysfunction grade 1 resolved by day three, with surveillance biopsies negative for any signs of rejection. At 24 months, the patient exhibited excellent outcomes, including predicted values of 75 % and 92 % for forced expiratory volume in one second (FEV1) and diffusing capacity, respectively, as well as preserved cardiac function and complete functional independence.

Comprehensive molecular analysis of explanted lungs revealed extensive necrosis, fibrosis, and homogeneous immune infiltration across all seven sampled regions, which resembled end-stage ARDS due to the coronavirus disease 2019 (COVID-19). Single-cell ribonucleic acid (RNA) sequencing identified 43 cell populations reflecting T-cell expansion, plasma cell differentiation, B-cell depletion, as well as the replacement of mature alveolar macrophages by profibrotic monocyte-derived macrophages.

Epithelial analysis revealed failed regeneration with aberrant basaloid cells and depleted alveolar type 2 cells. Spatial transcriptomics demonstrated complete architectural effacement with tertiary lymphoid structures and collagen triple helix repeat containing 1 (CTHRC1)-positive myofibroblasts driving fibrosis. These findings indicated diffuse severe disease with molecular signatures of irreversible end-stage injury, rather than recoverable ARDS.

Conclusions

The current case report discusses the successful use of a novel total artificial lung system following bilateral pneumonectomy for refractory septic ARDS that enabled hemodynamic stabilization and transplantation after 48 hours of support.

Comprehensive molecular analysis confirmed terminal lung injury in explanted lungs characterized by diffuse architectural destruction, pathologic immune infiltration, failed epithelial regeneration, and profibrotic remodeling, consistent with irreversible end-stage disease. At 24 months post-transplantation, the patient maintained excellent cardiopulmonary function and was completely independent.

Prospective validation of this artificial lung system is needed to define patient selection criteria and optimal timing, as well as identify molecular signatures that could distinguish irreversible from recoverable ARDS earlier in the disease course. Integration of the TAL system with advanced infection control and immunomodulatory strategies, combined with refined single-cell and spatial transcriptomic approaches, may expand transplant eligibility and facilitate the development of targeted therapeutics to prevent progression to terminal lung injury.