Recommendations relate to the grading system suggested by the European Society of Cardiology (ESC) and the American Heart Association (AHA), data derived from paediatric studies only (class, level of evidence).
BPD, bronchopulmonary dysplasia; CLD, chronic lung disease; nCLD, neonatal CLD; COR, class of recommendation; ECMO, extracorporal membrane oxygenation; iNO, inhaled nitric oxide; LOE, levels of evidence; PH, pulmonary hypertension; PPHN, persistent pulmonary hypertension of the newborn.