ARDS in Children and ECMO Initiation Strategies Impact on Neurodevelopment (ASCEND)

Inclusion Criteria: * Time between intubation and ECMO cannulation is less than 240 hours (10 days) * ECMO support type is respiratory (VV or VA cannulation) * Chest radiograph with bilateral lung disease * Moderate or severe pediatric ARDS as measured by oxygenation index or oxygen saturation index after intubation and prior to ECMO cannulation: One OI ≥ 16 or Two OIs ≥ 12 and ≤ 16 at least four hours apart or Two OSIs ≥ 10 at least four hours apart or One OI ≥ 12 and ≤ 16 and One OSI ≥ 10 at least four hours apart Exclusion Criteria: * Previously enrolled in PROSpect * Perinatal related lung disease * Congenital diaphragmatic hernia or congenital/acquired diaphragm paralysis * Respiratory failure caused by cardiac failure or fluid overload * Cyanotic congenital heart disease * Cardiomyopathy * Primary pulmonary hypertension (PAH) * Unilateral lung disease * Intubated for status asthmaticus * Obstructive airway disease * Bronchiolitis obliterans * Post hematopoietic stem cell transplant * Post lung transplant * Home ventilator dependent * Neuromuscular respiratory failure * Head trauma: (managed with hyperventilation) * Intracranial bleeding * Unstable spine, femur or pelvic fractures * Acute abdominal process/open abdomen * Family/medical team have decided to not provide full support * Enrolled in interventional clinical trial: not approved for co-enrollment; does not include cancer protocols. * Known pregnancy