Neurally adjusted ventilatory assist in preterm neonates with acute respiratory failure

Background: Neurally adjusted ventilatory assist (NAVA) is a novel mode of ventilation that has been demonstrated to improve infant-ventilator interaction, compared to the conventional modes in retrospective and short-term studies.

Objectives: To prospectively evaluate the physiologic effects of NAVA in comparison with pressure-regulated volume control (PRVC) in two nonrandomized 12-hour periods.

Methods: We studied 14 consecutive intubated preterm neonates receiving mechanical ventilation for acute respiratory failure. Peak airway pressure (Paw peak ), diaphragm electrical activity (EAdi), tidal volume (V T ), mechanical (RR mec ) and neural (RR neu ) respiratory rates, neural apneas, and the capillary arterialized blood gases were measured. The RR mec -to- RR neu ratio (MNR) and the asynchrony index were also calculated. The amount of fentanyl administered was recorded.

Results: Paw peak and V T were greater in PRVC (p < 0.01). Blood gases and RR mec were not different between modes, while RR neu and the EAdi swings were greater in NAVA (p = 0.02 and p < 0.001, respectively). MNR and the asynchrony index were remarkably lower in NAVA than in PRVC (p = 0.03 and p < 0.001, respectively). 1,841 neural apneas were observed during PRVC, with none in NAVA. Less fentanyl was administered during NAVA, as opposed to PRVC (p < 0.01).

Conclusions: In acutely ill preterm neonates, NAVA can be safely and efficiently applied for 12 consecutive hours. Compared to PRVC, NAVA is well tolerated with fewer sedatives.