Infants born between 28 and 32 weeks' gestation with radiological findings and clinical symptoms of moderate RDS, requiring respiratory support with Nasal Continuous Positive Airway Pressure (NCPAP) within the first hour of life, were randomized to receive either standard medical air or a Heliox/Oxygen mixture 80/20 (Heliox) during the first 12 hours of life, followed by medical air until NCPAP was needed. The aim of the study was to assess the therapeutic effects of breathing a low-density gas mixture (heliox: 80% helium and 20% oxygen) in premature babies with Respiratory Distress Syndrome (RDS), undergoing NCPAP in terms of reducing the rate of mechanical ventilation (MV).