The Strategy of "Pulmonary Opening by Titration of Positive End-expiratory Pressure" Means of a Pulmonary Recruitment Maneuver in Patients With Acute Respiratory Distress Syndrome: for Which Patients?

Inclusion Criteria: Will be included in the study, patients: * Major patient (age ≥18 years) * Controlled assisted ventilation, sedation and curarization adapted to the respirator. * Within the first 72 hours of an ARDS (PaO2 / FiO2 ≤ 200 mmHg, FiO2 ≥ 60% and PEEP of ≥5 cmH20) (as recommended by the Berlin criteria) * Decision of intensivist in charge of the patient to put an oesophageal probe * After hemodynamic optimization (evaluation of the preload dependence and need for catecholamines) * Decision of the intensivist in charge of the patient to perform a pulmonary opening test by titration of PEEP by means of a pulmonary recruitment test. Exclusion Criteria: * Patients under the age of 18 * Pregnant women, women who are parturient or breastfeeding * Patients with pulmonary broncho-emphysematous pathology or at risk of presenting it. * Patients with a history of barotrauma or at risk of presenting it. * Patients with a history of intracranial hypertension * Patients with suspected or proven right ventricular dysfunction or uncontrolled hemodynamic instability after hemodynamic management. * Patients with a contraindication to the placement of an oesophageal tube (esophageal surgery, severe esophageal pathology) * Patients under guardianship or curatorship or deprived of liberty. * Patients who are legally protected * Patient not covered by French national health insurance