Transition from VV to VA or hybrid ECMO: An ELSO Overview

ABSTRACT

Objective: The use of veno-venous extracorporeal membrane oxygenation (V-V ECMO) has increased significantly in the last years, and in particular in the recent pandemic COVID-19, representing a valuable therapy to treat severe respiratory failure. However, few patients remain hypoxemic and become hemodynamically instable during V-V ECMO support requiring a change in ECMO configuration. Methods: The Extracorporeal Life Support Organization Registry was reviewed for all cases of adult ARDS in patients undergoing ECMO requiring a change in configuration during the support run. (2017 to 2019). All main aspects, if available, characterizing the patients undergoing ECMO support modifications were collected and analyzed in terms of incidence, causes, patterns, complications and outcomes. Results: Of 9936 V-V ECMO runs, there were 354 ECMO that requiring a in changing configurations (3,5%). Over the study period the proportion of ECMO changing configuration was 1,3% (136) for VA, 1,6% (166) for V-VA and 0,8(85%) for Other configurations with an increasing in configuration changing during the years. The mortality rate in the shifting population was 55%. The new configurations were associated with major bleeding, stroke and renal failure was similar. Main determinants of poor outcome were the severity of the underlying illness, the delay in recognizing evolution of the disease, the complications associated with the conversion itself, and the more complex management of the hybrid setting. Conclusions: Our review of ARDS patients showed the variation in configuration VA ECMO or Hybrid ECMO was not associated with worse survival but with a high rates of complications rates compared with VV ECMO. These data suggest that in very selected patients it may reasonable to initially instituted VV ECMO support, reserving VA or Hybrid ECMO forms for conversion for refractory cardiopulmonary failure and cardiogenic shock that represent the major reasons of VV ECMO failure.