Neurally Adjusted Ventilatory Assist in Preterm Infants With Established or Evolving Bronchopulmonary Dysplasia on High-Intensity Mechanical Ventilatory Support: A Single-Center Experience

Objectives: The aim of the present study was to report possible improvements in ventilator variables associated with a transition from synchronized intermittent mandatory ventilation to neurally adjusted ventilatory assist in preterm infants with bronchopulmonary dysplasia who required a high level of mechanical ventilatory support in a single center. Design: Retrospective study. Setting: Neonatal ICU. Patients: Twenty-nine preterm infants with a median gestational age of 25.4 weeks (range, 23.4-30.3 wk) and a median birth weight of 680 g (range, 370-1,230 g) and who were supported with a mechanical ventilator for more than 4 weeks and had a respiratory severity score greater than four during conventional mechanical ventilation prior to conversion to neurally adjusted ventilatory assist. Interventions: Comparison of ventilatory variables, work of breathing, and blood gas values during conventional ventilation and at various time intervals after the change to neurally adjusted ventilatory assist. Measurements and Main Results: The values of various ventilatory variables and other measurements were obtained 1 hour before neurally adjusted ventilatory assist and 1, 4, 12, and 24 hours after conversion to neurally adjusted ventilatory assist. During neurally adjusted ventilatory assist, the peak inspiratory pressure (20.12 +/- 2.93 vs 14.15 +/- 3.55 cm H2O; p < 0.05), mean airway pressure (11.15 +/- 1.29 vs 9.57 +/- 1.27 cm H2O; p < 0.05), and work of breathing (0.86 +/- 0.22 vs 0.46 +/- 0.12 J/L; p < 0.05) were significantly decreased, and the blood gas values were significantly improved. Significantly lower FIO2 and improved oxygen saturation were observed during neurally adjusted ventilatory assist compared with conventional ventilation support. The RSS values decreased and sustained during neurally adjusted ventilatory assist (4.85 +/- 1.63 vs 3.21 +/- 1.01; p < 0.001). Conclusions: The transition from synchronized intermittent mandatory ventilation to neurally adjusted ventilatory assist ventilation was associated with improvements in ventilator variables, oxygen saturation, and blood gas values in infants with bronchopulmonary dysplasia in a single center. This study suggests the possible clinical utility of neurally adjusted ventilatory assist as a weaning modality for bronchopulmonary dysplasia patients in the neonatal ICU.