Lung Transplant Outcomes for COVID Respiratory Failure Similar to Other Etiologies

Patients who received lung transplants due to irreversible respiratory failure from SARS-CoV-2 infection had similar outcomes to those who received lung transplants for other reasons, a retrospective study found.

Among 195 patients with COVID-19-related acute respiratory distress syndrome (ARDS) who underwent lung transplants, 1-, 6-, and 12-month overall survival rates were 99%, 95%, and 88%. For 190 patients who had COVID-19-related pulmonary fibrosis, survival rates were 96%, 92%, and 84%, respectively.

Freedom from graft failure rates at 1, 6, and 12 months were 98%, 95%, and 88% in the ARDS cohort and 96%, 93%, and 85% in the fibrosis cohort, respectively, reported Panagiotis Tasoudis, MD, of the University of North Carolina at Chapel Hill, and co-authors in JAMA Surgery.

There were no significant differences in overall survival between transplant recipients with COVID-19-related lung diseases versus non-COVID-19 related transplant recipients (adjusted hazard ratio 0.79, 95% CI 0.54-1.16, P=0.23).

Traditionally, transplants have not been seen as a therapeutic option for patients with acute lung injury from infection, Tasoudis and co-authors observed.

"Nevertheless, during the COVID-19 pandemic, thousands of infected patients experienced irreversible lung injury requiring extended periods of mechanical life support with ECMO [extracorporeal membrane oxygenation], mechanical ventilation, or both," the researchers wrote. "In these critically ill patients who did not show sufficient response to medical therapy and did not recover despite prolonged hospitalization and optimized care, lung transplant became a life-saving option."

"To our knowledge, this study represents the largest series to date of patients receiving lung transplants for both COVID-19-related ARDS and COVID-19-related PF [pulmonary fibrosis]," they noted.

The study used data from the Organ Procurement and Transplantation Network and United Network for Organ Sharing (UNOS) Standard Transplant Analysis and Research, and included 385 patients who underwent lung transplant due to COVID-related ARDS or pulmonary fibrosis from March 2020 to August 2022. Patients younger than 18, who were listed for more than one organ transplant, or who had repeat transplants were excluded.

Median follow-up was 186 days in the ARDS group and 181 days in the pulmonary fibrosis group. Median ages were 46 and 54 years, respectively, and the cohorts were 27% and 21% female, and 55% and 56% white.

Overall, 19.6% of the ARDS group and 28.2% of the fibrosis group had a smoking history. Median lung allocation scores -- assigned on a 0-100 scale, with higher scores indicating higher lung transplant need -- were 88.3 for the ARDS cohort and 78.5 for the pulmonary fibrosis cohort.

On postoperative day 3, a total of 55 patients in the ARDS group (30.1%) and 35 in the fibrosis group (20.0%) required ECMO support. During follow-up, 8.7% and 8.6%, respectively, experienced an acute rejection episode. Median hospital stay was 30 and 22 days.

"We reason that the high prevalence of critical illness in our recipient cohorts and high rates of primary graft dysfunction explain why more than half of patients undergoing transplant remained intubated more than 3 days postoperatively, and that one-fourth of the patients remained on ECMO for similar periods," Tasoudis and co-authors wrote. Critical illness also may have been behind long hospital stays, they noted.

Patients in the ARDS group who received a lung from a donor with a heavy and prolonged smoking history had significantly worse survival outcomes, the researchers pointed out. While other studies also have reported this, it's possible that "patients who received grafts from such donors were critically ill and urgently scheduled for transplant despite the less-than-ideal quality grafts as a salvage therapy for their disease."

The study adds to the accumulating evidence about lung transplant for patients who experience irreversible damage due to COVID-19, noted Ankit Bharat, MD, and Emily Cerier, MD, both of Northwestern University in Chicago, in an accompanying commentary.

"[W]ith the expected recession of the pandemic, we anticipate a decline in double-lung transplant for COVID-19 ARDS," Bharat and Cerier wrote. "Nevertheless, insights learned from lung transplants for COVID-19 could be extended to patients battling other causes of ARDS -- a severe global health care issue with high mortality, affecting over 100,000 patients annually in the U.S. alone."

The findings should be interpreted with caution due to inherent limitations in the study's design and the lack of individual patient data, Tasoudis and colleagues noted. Details like time intervals from respiratory failure until transplant, association of intraoperative variables with outcomes, and information on preoperative biopsy, among others, were not available.

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