Linking Endotypes and Outcomes in Pediatric Acute Respiratory Distress Syndrome

Inclusion Criteria: 1. acute (≤ 7 days of risk factor) respiratory failure requiring invasive mechanical ventilation 2. age \> 44 weeks corrected gestational age and \< 17.5 years 3. invasive mechanical ventilation via endotracheal tube 4. bilateral infiltrates on chest radiograph 5. oxygenation index (OI) ≥ 4; or oxygen saturation index (OSI) ≥ 5 on 2 consecutive measurements at least 4 hours apart but \< 24 hours apart 6. invasively ventilated ≤ 7 days before meeting above radiographic and oxygenation criteria Exclusion Criteria: 1. weight \< 3 kilograms 2. cyanotic congenital heart disease (other than Patent Foramen Ovale (PFO) or Patent Ductus Arteriosus (PDA)) 3. tracheostomy at time of screening 4. invasively ventilated for \> 7 days when meet ARDS criteria above 5. cardiac failure as predominant cause of respiratory failure 6. primary obstructive airway disease (asthma, bronchiolitis) by judgement of clinician as the primary cause of respiratory failure 7. alternative known chronic lung disease as cause of respiratory failure (cystic fibrosis, eosinophilic pneumonia, interstitial pneumonitis, pulmonary hemosiderosis, cryptogenic organizing pneumonia) 8. severe neurologic morbidity not expected to survive \> 72 hours 9. any limitations of care at time of screening 10. previous enrollment in this study