Crossover study of assist control ventilation and neurally adjusted ventilatory assist

Some studies of infants with acute respiratory distress have demonstrated that neurally adjusted ventilator assist (NAVA) had better short-term results compared to non-triggered or other triggered models. We determined if very prematurely born infants with evolving or established bronchopulmonary dysplasia (BPD) had a lower oxygenation index (OI) on NAVA compared to assist control ventilation (ACV). Infants were studied for 1 h each on each mode. At the end of each hour, blood gas analysis was performed and the OI calculated. The inspired oxygen concentration (FiO(2)), the peak inflation (PIP) and mean airway pressures (MAP) and compliance were averaged from the last 5 min on each mode. Nine infants, median gestational age of 25 (range 22-27) weeks, were studied at a median postnatal age of 20 (range 8-84) days. The mean OI after 1 h on NAVA was 7.9 compared to 11.1 on ACV (p = 0.0007). The FiO(2) (0.36 versus 0.45, p = 0.007), PIP (16.7 versus 20.1 cm H2O, p = 0.017) and MAP (9.2 versus 10.5 cm H2O, p = 0.004) were lower on NAVA. Compliance was higher on NAVA (0.62 versus 0.50 ml/cmH(2)O/kg, p = 0.005). Conclusion: NAVA compared to ACV improved oxygenation in prematurely born infants with evolving or established BPD.