Introduction: In recent years there has been an increased use of nasal continuous positive airway pressure (nCPAP) in the management of premature infants with respiratory distress syndrome (RDS). The use of early nCPAP eliminates the need for endotracheal intubation and mechanical ventilation, and their associated morbidities. In clinical practice a significant number of extremely low birth weight (ELBW) infants with RDS fail nCPAP therapy within the first 72 hours of life and require rescue endotracheal intubation. The clinical factors resulting in nCPAP failure are hypoxemia, hypoventilation, muscular fatigue and/or apnea. Helium is a biologically inert gas that is used in medicine as a carrier for oxygen. Heliox (mixture of helium and oxygen) has been used safely in neonates for decades and its use has been consistently been shown to improve oxygenation, enhance ventilation and decrease the work of breathing. Prior studies using heliox in the management of premature infants with RDS have shown clear therapeutic benefits. The use of heliox delivered via a nCPAP device (Hx-nCPAP) has recently been reported in infants with bronchiolitis. Given the prior success of heliox in the management of RDS combined with the recent advent of Hx-nCPAP we intend to investigate the utility of Hx-nCPAP in reducing the incidence of early nCPAP failure in ELBW infants with RDS.