Work of Breathing Description in Neonates With Congenital Diaphragmatic Hernia in NAVA and in Conventional Ventilation.

While the patient is under respiratory assistance on the SERVO-I respirator, he will be included in the study and one esophageal transducer of 2,3 mm of diameter will be inserted through the mouth / nose in addition to NAVA's naso / Oro-Gastric tube( Edi Catheter, 6Fr, 49 cm, PHT free 5 pcs / pkg or Catheter Edi, 6Fr, 50 cm, PHT free 5 pcs / pkg). Measurements will be performed using the esophageal transducer under two conditions: 2 hours in conventional ventilation (pressure controlled), 2 hours in NAVA ventilation and then again 2 hours in conventional ventilation (PC) for a total duration of 6 hours.The parameters of conventional ventilation will be left free at the choice of the neonatologist and will be identical between the two periods of conventional ventilation. The initial NAVA level will be defined by the neonatologist using pre-visualization curves. All signals will be recorded via an amplification and acquisition system. Values will be averaged over 100 cycles.