Extracorporeal membrane oxygenation bridge to transplant in the era of the lung composite allocation score

The lung composite allocation score (CAS) aims to improve waitlist outcomes for lung transplant candidates by prioritizing characteristics that reflect transplant urgency, including extracorporeal membrane oxygenation bridge to lung transplant (ECMO-BTT). Whether ECMO-BTT has been impacted by CAS is unknown. We analyzed the Organ Procurement and Transplant Network database to examine differences in ECMO-BTT utilization and characteristics and outcomes between transplant recipients who were transplanted one year before and one year after CAS implementation. Lung transplant recipients who received ECMO-BTT in the post-CAS era were younger (<i>p</i> < 0.01), more likely to be on ECMO at transplant listing rather than be initiated after (<i>p</i> < 0.05), and had shorter waitlist time (<i>p</i> < 0.01). Waitlist time was shorter in the post-CAS era among recipients (even non-ECMO) with high allocation scores only. This may have contributed to decreased use of ECMO-BTT in the post-CAS era (<i>p</i> = 0.03). One-year post-transplant survival did not differ between eras for ECMO-BTT patients, though was significantly better in the CAS era for non-ECMO-BTT patients (92% vs 90%, <i>p</i> < 0.01). We report initial results of ECMO-BTT utilization in the post-CAS era.