We speculate that low vascular endothelial growth factor levels in tracheal aspirate fluid, concurrent with elevated soluble vascular endothelial growth factor receptor 1 levels on the first day of life, are biological markers for the development of bronchopulmonary dysplasia/chronic lung disease in very low birth weight infants requiring O(2) and assisted mechanical ventilation.

The antioxidant status is low in preterm infants at risk for developing hsPDA. SOD may be a key antioxidant regulating functional ductus arteriosus closure. Therefore, low levels may result in persistence of a hsPDA.

Avastin treatment in IH has lasting alterations in the balance between MMPs and their tissue inhibitors. These changes may lead to impaired alveologenesis and tissue damage consistent with bronchopulmonary dysplasia/chronic lung disease.