Inhaled Nitric Oxide for the Treatment of Neonatal Hypoxic Respiratory Failure With Pulmonary Hypertension

Inclusion Criteria: 1. Neonates ≥ 34 weeks gestation age. 2. Hypoxic respiratory failure requiring more than 24 hours of ventilatory support. 3. Clinical or echocardiographic evidence of pulmonary hypertension (systolic pulmonary arterial pressure \[sPAP\] \> 35 mm Hg or \> 2/3 systemic blood pressure \[SBP\] or there is a right-to-left shunt at the atrium or arterial ductus). 4. Age less than 7 days at the time of treatment initiation with study drug. 5. The neonatal guardian agrees to participate in the study and signs an informed consent form (ICF). Exclusion Criteria: 1. Neonates dependent on right-to-left shunting of blood. 2. Neonates whose mother has been treated with anticoagulant therapies during pregnancy. 3. Echocardiography confirmed left-to-right shunt or left ventricular dysfunction. 4. ECMO is urgently needed, or neonate has received ECMO. 5. Patient is at risk of imminent death (death expected within 24 hours). 6. Life-threatening abnormality (cranial, cardiac, thoracic). 7. Chromosomal abnormality. 8. Congenital diaphragmatic hernia 9. Congenital heart defect (other than patent ductus arteriosus or small atrial septal defect). 10. Neonate has been resuscitated requiring chest compressions within 6 hours of study treatment start. 11. Significant bleeding diathesis such as grade IV intraventricular hemorrhage or periventricular leukomalacia, pulmonary hemorrhage, uncontrolled bleeding or hemodynamic failure. 12. Disseminated intravascular coagulopathy. 13. Active seizures while receiving anticonvulsants. 14. Experienced prolong asphyxia with evidence of severe acidosis (pH\<7.25) 15. Receiving nitric oxide donor agents such as prilocaine, sodium nitroprusside, nitroglycerin, and sulfonamides. 16. Other subjects determined by the investigator to be unsuitable for inclusion.