Work of Breathing in Bronchiolitis Under Non-invasive Ventilation

"Catheter placement : at least 2 hours after and within 24 hours following the initial ventilation support establishment (CPAP or NiPPV according to usual practice and clinical conditions). 2 periods of measurements : with the initial and with the 2nd ventilation support using a cross-over for each patient. For each period, the first serie of measurements will be carried out without modifying the settings of the support ( clinical setting), and the second one using esogastric pressures by adjusting the settings of the ventilation support in order to obtain an optimal normalization or reduction of the amplitude of the Pes and Pdi deltas (physiological setting). 5 minutes of spontaneous breathing with/without oxygen between period 1 and 2 (depending on the patient's conditions). All measurements will be performed for 5 minutes after a 15 minutes quiet breathing. After measurements, the optimal respiratory support will be continued."