Respiratory Pattern During Neurally Adjusted Ventilator Assist (NAVA) in Preterm Infants

This study is to investigate the effect of a wide range of assistance levels on respiratory pattern, breathing variability including tidal volume and peak inspiratory pressure during neurally adjusted ventilatory assist (NAVA) in preterm infants. The investigators also aim to explore whether the effects of NAVA on the electrical activity of diaphragm (Edi) signal amplitude, work of breathing and comfort of preterm infants.

Inclusion Criteria:

• preterm infants born before 36 weeks of gestational age
• who received mechanical ventilatory care through the endotracheal tube at least 24 hours for respiratory distress
• no use of anesthetics or analgetics

Exclusion Criteria:

• with major congenital anomalies (facial, gastrointestinal tract, cardiac, etc)
• with phrenic nerve palsy or injuries