In patients suffering from early Acute Respiratory Distress Syndrome (ARDS), an algorithm for individual adjustment of positive end-expiratory pressure and tidal volume will be applied. After optimization of ventilator settings according to the ARDS Network protocol, lung stress and strain, driving pressure, respiratory system compliance (Crs), regional ventilation delay and PaO2 / FiO2 ratio will be recorded. Subsequently, ventilator settings will be adjusted using an algorithm aiming at recruitment and avoiding tidal recruitment and overdistension using electrical impedance tomography (EIT). After 4 hours of EIT-based optimization ventilator settings, lung stress and strain, driving pressure, respiratory system compliance (Crs), regional ventilation delay and PaO2 / FiO2 ratio will be recorded again. The results will be compared to the ARDS Network approach.