Neurally adjusted ventilatory assist in weaning of neonates affected by congenital diaphragmatic hernia

Objective: The aim of the study is to evaluate the application of neurally adjusted ventilatory assist (NAVA) in the respiratory weaning of patients affected by congenital diaphragmatic hernia (CDH). Methods: We analyzed the NAVA weaning in 12 neonates affected by CDH, relating the effectiveness of the electrical activation of the diaphragm (EAdi) signal to the type of CDH repair (with or without patch), the size of the patch, the stomach and His angle position, and the trend evaluation of some cardiorespiratory parameters with NAVA compared to pressure-support-ventilation (PSV). Results: 5 neonates submitted to primary repair showed a regular EAdi signal and were successfully weaned with NAVA. Of the seven patients submitted to patch repair, five operated with patch limited to the diaphragmatic postero-lateral area had an active EAdi signal that permitted weaning with NAVA. Only in two neonates with hemidiaphragm agenesis was NAVA not feasible due to the impossibility to capture the EAdi signal. Compared to PSV, NAVA allows a significant improvement of oxygenation-linked indexes and paCO2, while PIP is reduced. Conclusion: Neonatal CDH with a postero-lateral diaphragmatic defect allows the NAVA catheter to obtain a correct EAdi signal and develop a viable NAVA ventilation. The lower risk of lung injury in NAVA appears compatible with current ventilatory strategies considered useful in CDH