Mechanical ventilation and extracorporeal membrane oxygenation as a bridge to lung transplantation: Closing the gap

Abstract

Background: The purpose of this study was to examine outcomes and survival with mechanical ventilation (MV) and extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplantation (LT) using a national registry.

Methods: The United Network for Organ Sharing database was analyzed for recipients in the period 2005 to 2017. Recipients were categorized into 3 groups based on pre-transplant bridging. Multivariable regression analyses examined the effect of bridging on post-LT outcomes adjusting for clinical characteristics, including era (early = 2005-2011, late = 2012-2017) and center volume.

Results: There were 21,576 LT recipients: no bridge (n = 19,783), MV (n = 1,129), and ECMO (n = 664). Mean age was 54 ± 15 years (41% female). Use of ECMO increased significantly in the late era (1% vs 5%, p < 0.001). Compared with no bridge, patients with MV and ECMO had greater odds for peri-operative outcomes including ventilator support >48 hours, acute rejection, and dialysis. Patients with MV had reduced odds for ventilator support >48 hours (p = 0.003), dialysis (p = 0.003), post-operative ECMO (p = 0.006), and greater odds for reintubation (p = 0.005) compared with ECMO. Patients in both MV (hazard raio [HR] 1.45, p < 0.001) and ECMO (HR 1.48, p < 0.001) groups had greater risk for 5-year mortality, but MV and ECMO groups did not differ (HR 0.98, p = 0.817). Risk for mortality in the ECMO group decreased in the later era (HR 0.54, p = 0.006).

Conclusions: ECMO as a bridge to LT has increased 271%, while MV has decreased 38% over the past decade. Survival with ECMO has significantly improved and is now equivalent to survival in recipients bridged on MV. These results suggest gains in use, outcomes, and safety of ECMO in this patient cohort.

Keywords: bridge to transplantation; extracorporeal membrane oxygenation; lung transplantation; mechanical support; mechanical ventilation.