Individualized Or Conventional Transfusion Strategy During Veno-Arterial Extracorporeal Membrane Oxygenation Support...

Red blood cell (RBC) transfusion practices during veno-arterial extracorporeal membrane oxygenation (VA-ECMO) are heterogeneous, and the benefit - harm balance remains uncertain. Current recommendations rely on predefined hemoglobin thresholds and do not provide criteria for individualized transfusion. As the primary goal of RBC transfusion is to optimize oxygen delivery (DO₂) to meet oxygen consumption (VO₂), a strategy guided by a surrogate of DO₂/VO₂ mismatch - central venous oxygen saturation (ScvO₂)- may be more appropriate than fixed liberal transfusion thresholds.

ICONE is a multicenter, randomized, controlled trial comparing two transfusion strategies in adult patients supported by VA-ECMO for refractory cardiogenic shock. Patients are randomized 1:1 and stratified according to postcardiotomy versus medical etiology to either individualized or conventional transfusion strategy. In the individualized group, transfusion is triggered by ScvO₂ <65% despite optimization of VO₂ determinants. In the conventional group, transfusion was triggered by hemoglobin <9 g/dL. The primary endpoint is the number of RBCs units transfused per day of ECMO support. Secondary outcomes include 28-day composite of major adverse outcomes (key secondary endpoint), 90-days all-cause mortality, rate of organ failure, transfusion-related immune and non-immune complications (including human leucocyte antigen allosensitization) and cost effectiveness. A total of 236 patients provides 80% power to detect a 25% reduction in the primary endpoint and in key secondary outcomes using a two-sided test at 0.05 significance level (considering hierarchical testing framework) and considering 5% drop out. The study was registered in April 2020 (NCT05699005; IDRCB 2021-A01925-36) and is currently recruiting.

The ICONE trial may contribute to changing transfusion practice in VA-ECMO.