Interest of High Flow Nasal Cannula (HFNC) Versus Non Invasive Ventilation During the Initial Management of Severe Bronchiolitis in Infants

1. The purpose of the study is to evaluate prospectively the clinical benefits of High flow nasal canula (HFNC: 2l/kg/min) versus nasal CPAP( continuous positive airway pressure) (n-CPAP: 7 cmH2O) in the initial management of bronchiolitis in infants. 2. Design: non-inferiority study, prospective, controlled, randomized, multi-center. 3. Design: Infants less than 6 month admitted in pediatric intensive care unit for respiratory distress (mWCAS \>3) secondary to bronchiolitis but not requiring mechanical ventilation will be randomized in two groups: \"n-CPAP\"(nasal continuous positive airway pressure) or \"HFNC\" during 24 hours. 4. Conditions of measurements: Primary endpoint: Proportion of failure in both arms during the first 24 hours. Failure criteria: A raise of the Clinical score for respiratory distress (mWCAS) (1 point) or respiratory rate (10/min /H0 and above 60/min) or discomfort (EDIN) (1point /H0 and above 4) or apnea. Secondary outcomes: Assessment at H1, H12, H24 of mWCAS, respiratory and heart rate, EDIN score, skin lesions, FiO2 (fraction of inspired oxygen ) required to achieve an oxygen saturation between 94 and 97%, transcutaneous PCO2 (carbon dioxide partial pressure) (correlated to an initial gas analysis), Report SpO2 / FiO2 5. Statistic: Intention to treat Analysis. Expected number of patients: 71 per arm: 142 children. 6. Study Schedule: October 2014-April 2016