Extracorporeal membrane oxygenation (ECMO) for severe acute respiratory distress syndrome (ARDS). The EOLIA (ECMO to rescue Lung Injury in severe ARDS) trial: a multicenter, international, randomized, controlled open trial

Abstract

The acute respiratory distress syndrome (ARDS) remains associated with an elevated rate of mortality that may exceed 60% in the most severe cases with a refractory hypoxemia. In these situations, the use of an extracorporeal membrane oxygenation (ECMO), combining a centrifugeal pump and an oxygen membrane, was proposed. The aim of ECMO is to minimize the trauma induced by mechanical ventilation (MV) and to allow the lungs to rest. The objective of this multicenter, international, randomized, open trial is to evaluate the impact on the morbidity and mortality of ECMO, early instituted after the diagnosis of an ARDS with an unfavorable outcome after 3–6 hours despite optimal ventilatory management and maximum medical treatment. Included patients will fulfill the following criteria: ARDS defined according to the usual criteria and PaO₂/FiO₂ ratio < 50 mmHg with FiO₂ ≥ 80% for > 3 hours, despite the optimization of mechanical ventilation and use of adjunctive therapies or PaO₂/FiO₂ < 80 mmHg with FiO₂ ≥ 80% for > 6 hours, despite the optimization of mechanical ventilation and use of adjunctive therapies or pH < 7.25 for > 6 hours (despite an increase of the respiratory rate up to 35/min) resulting from MV settings adjusted to keep a plateau pressure ≤ 32 cmH₂O. In the control arm, standard ARDS management according to the modalities used for the “maximal pulmonary recruitment” group in the EXPRESS trial, will be performed. The primary endpoint is to achieve with ECMO a significantly lower mortality on day 60 following the randomization. With a 80%-power and a 5%-alpha-risk for the hypothesis of ECMO achieving a 20%-absolute mortality reduction and an estimated probability of 60%-mortality in the control arm, the characteristics of the study, calculated with a triangle test, indicate a 90%-probability of stopping the study before the inclusion of 220 subjects. This project will be conducted within the REVA (European network for research in mechanical ventilation).