Automation Oxygen Flow Titration in Spontaneously Breathing Infants

Inclusion Criteria: * Infants from 1 month of age and less than 1 year of age who present a first episode of bronchiolitis and require oxygen therapy * Informed consent of parents (written informed consent will be obtained from the patients' parents or legally authorized representatives) * Affiliation to the French social security system Exclusion Criteria: * Need for oxygen flow higher than 3 L / min to maintain SpO2 greater than 92% * Patient with severity criteria according to the 2019 French National Authority for Health (HAS) guidelines and for whom it's indicated to maintain SpO2 above 94% * Criteria of severity justifying from the start another technique of assisted ventilation: * Polypnea: respiratory rate (FR)\> 80 c / min. * Consciousness with glasgow score (GSC) \<or = 12. Hemodynamic instability (mean arterial pressure (MAP) \<- 2 SD for age or use of vasopressors). * Cardiac or respiratory arrest. * PCO2\> 55 mm Hg and pH \<7.20 when blood gas are performed * Need for urgent surgery * Contraindication to the FreeO2 device as described in the user manual * Lack of informed consent from parents * Premature birth with a gestational age at birth under 36 weeks * Severe co-morbidities (cystic fibrosis, immune deficiency, congenital heart disease, neuromuscular illness)