Open Lung Strategy, Gas Distribution and Right Heart Function in ARDS Patients

Inclusion Criteria: * ARDS diagnosis within 72h after intubation * Severe to moderate ARDS (PaO2 / FiO2 \< 200 mmHg) with PEEP\>5 cmH2O * Presence of an arterial line * Between 18 and 85 years old Exclusion Criteria: * Persistent systolic blood pressure \< 90 mmHg and/or \>180 mmHg despite the use of vasopressor or vasodilators * Increment in vasopressors over the past two hour just before enrollment of: more than 15 mcg/min for norepinephrine and dopamine, more than 10 mcg/min in epinephrine; and more than 50 mcg/ min for phenylephrine. * Advanced lung disease confirmed by computed tomography findings * Presence or history of pneumothorax * Severe coagulopathy (INR ≥ 4) * Severe thrombocytopenia (Platelets count ≤ 5,000/mm3) * Usage of any devices with electric current generation such as pacemaker or internal cardiac defibrillator * Recent esophageal trauma or surgery * Known presence of esophageal varices * Pregnancy