Personalized Ventilation Based on Ventilation-perfusion Mismatch and Lung Recruitability

Inclusion Criteria: 1. age ≥18 years 2. Moderate-to-severe ARDS as per the 2023 ESICM definition 3. Undergoing invasive mechanical ventilation 4. Planned prone position based on the attending physicians' decisions 5. Signed informed consent Exclusion Criteria: 1. age ≥85 years 2. Pregnancy 3. Severe hemodynamic instability (\> 30% increase in vasopressors in the last 6 hours or norepinephrine \> 0.5 µg/kg/min) 4. Clinically suspected elevated intracranial pressure (\>18 mm Hg) 5. Bronchopleural fistula 6. Contraindication to EIT monitoring (e.g. burns, pacemaker, thoracic wounds limiting electrode belt placement) 7. Severe hypernatremia (\>170mmol/L) 8. Re-admission of patients already enrolled in this study, or patients who are participating in other studies