Supplementary Material for: Neurally Adjusted Ventilatory Assist in Preterm Neonates with Acute Respiratory Failure

<b><i>Background:</i></b> 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. <b><i>Objectives:</i></b> To prospectively evaluate the physiologic effects of NAVA in comparison with pressure-regulated volume control (PRVC) in two nonrandomized 12-hour periods. <b><i>Methods:</i></b> We studied 14 consecutive intubated preterm neonates receiving mechanical ventilation for acute respiratory failure. Peak airway pressure (Paw<sub>peak</sub>), diaphragm electrical activity (EAdi), tidal volume (V<sub>T</sub>), mechanical (RR<sub>mec</sub>) and neural (RR<sub>neu</sub>) respiratory rates, neural apneas, and the capillary arterialized blood gases were measured. The RR<sub>mec</sub>-to-RR<sub>neu</sub> ratio (MNR) and the asynchrony index were also calculated. The amount of fentanyl administered was recorded. <b><i>Results:</i></b> Paw<sub>peak</sub> and V<sub>T</sub> were greater in PRVC (p < 0.01). Blood gases and RR<sub>mec</sub> were not different between modes, while RR<sub>neu</sub> 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). <b><i>Conclusions:</i></b> 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.