nHFOV Versus Invasive Conventional Ventilation for Preterm Neonates With Respiratory Distress Syndrome

Inclusion Criteria: * Inborn Preterm Neonates 26-34 weeks gestation admitted to NICU with diagnosis of RDS * Babies who were initially started on High Flow Oxygen Therapy/nCPAP but unable to maintain saturation \> 90% on fio2 of 40% in 1st 6 hours of life. * Capillary PCO2 of \> 70 or arterial PCO2 \> 65 on two repeated sampling within 4 hours * Neonates whose parents consented to participate. Exclusion Criteria: * All preterm babies who are below \< 26 weeks above the 34 weeks of gestation * Preterm neonates (26-34 weeks) with diagnosis of RDS requiring endotracheal intubation within Labor room/Operation Theater or within 1st hour of life for respiratory support. * Preterm Neonates with the gestational age of 26-34 weeks, diagnosed as congenital pneumonia or sepsis. * Patient with poor respiratory drive due to any reason neurological or central causes * Diaphragmatic hernia or any other thoracic anomaly * Pleural effusion unilateral or bilateral * Congenital cystic pulmonary malformation. * Neonates with underlying cyanotic heart disease. * Neonates with acynotic heart disease causing pulmonary edema * Neonates with cleft lip and cleft palate or any other surgical condition.