"Continuous Positive Airway Pressure on Venovenous extracorporeaL Membrane Oxygenation for Acute respIratory Distress syndrOme"

Near apneic ventilation will be use during the first 3 days of ECMO. Patients will be ventilated in BIPAP/APRV or pressure-controlled ventilation. PEEP will be set to maintain the same mean airway pressure obtained during the standardized ventilation period pre-randomization to prevent lung derecruitment (PEEP ≥15cmH2O). If BIPAP/APRV is used, an RR of 2-4/min will be set with high pressure set at 30cmH20 for 3 sec. If pressure-controlled ventilation is selected, a respiratory rate of two sigh breaths/min with 30 cmH2O plateau pressure will be applied. Each sigh breath will be of three seconds duration. Neuromuscular blockade and sedation could be used at the discretion of the attending physician. After 3 days on ECMO, apneic ventilation could be pursued (at the physician's discretion). If not, ultra-protective lung ventilation will be applied (i.e standard of care). Prone positioning on ECMO will be left to the physicians' discretion.

Ultra-protective lung ventilation will be used up to the ECMO weaning. This group will receive ultra-protective lung ventilation with BIPAP/APRV or VCV mode setting a PEEP \>10 cmH2O, ΔP 14-15 cmH2O, RR 15-20/min, Vt 3-4ml/kg and lowest FiO2 to maintain SpO2\>92%. The use of prone positioning during ECMO will be left at the physician's discretion.