Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome

ECMO will be initiated as rapidly as possible by venovenous access. The material to be used consists of pre-heparinized cannulae and tubing, a centrifuge pump (CardioHelp®) and a heparinized membrane oxygenator (Quadrox®, Jostra®, Maquet®). To minimize the trauma induced by mechanical ventilation, the following ventilator settings will be used: volume-assist control mode, FiO2 30-60%, PEEP ≥10 cm H2O, VT lowered to obtain a plateau pressure \<25 cm H2O, respiration rate (RR) 10-30/minute or APRV mode with high pressure level \<25 cm H2O and low pressure level ≥10 cm H2O

Standard management of ARDS, according to the modalities applied by the 'maximal pulmonary recruitment' group in the EXPRESS trial (1): assist-controlled ventilatory mode, VT set at 6 ml/kg of ideal body weight and PEEP set so as not to exceed a plateau pressure of 28-30 cm H2O. In the case of refractory hypoxemia, the usual adjunctive therapeutics can be used: NO, prone position, HFO ventilation, almitrine infusion. A cross-over option to ECMO will be possible in the case of refractory hypoxemia defined as blood arterial saturation SaO2 \<80% for \>6 hours, despite mandatory use of recruitment maneuvers, and inhaled NO/prostacyclin and if technically possible a test of prone position, and only if the patient has no irreversible multiple organ failure and if the physician in charge of the patient believes that this could actually change the outcome