RESUMO
BACKGROUND: Our objective was to evaluate the feasibility, the quality of synchronization, and the influence on respiratory parameters of the noninvasive neurally adjusted ventilatory assist (NIV-NAVA) mode in infants after cardiac bypass surgery. We conducted a prospective, randomized cross-over study in infants undergoing noninvasive ventilation (NIV) after cardiac surgery. METHODS: Subjects were 10 infants < 5 kg. After extubation, subjects underwent 2 consecutive ventilatory modes after randomization into groups. In the CPAP first group, the subjects were ventilated first in nasal CPAP-1 and then in NIV-NAVA-2 for 30 min in each mode. In the NIV-NAVA first group, periods were reversed. All children were ventilated using the same interface. RESULTS: The analysis of curves showed a synchronization rate of 99.3% for all respiratory cycles. The rate of pneumatic inspiratory trigger was 3.4%. Asynchronies were infrequent. Some typical respiratory patterns (continuous effort and discontinuous inspiration) were found at rates of 10.9% and 31.1%, respectively. The respiratory trends showed a lower maximum diaphragmatic electrical activity (EAdi(max)) in NIV-NAVA periods compared with CPAP periods (P < .001 in the beginning of periods). The breathing frequency decreased significantly during the nasal CPAP-2 and NIV-NAVA-1 periods (P < .05). The inspiratory pressure increased significantly during the NIV-NAVA-1 and NIV-NAVA-2 periods (P < .05), but there was no significant difference for each parameter when comparing Δ values between the beginning and the end of each period. The EAdi signal was easy to obtain in all subjects, and no major side effects were associated with the use of NIV-NAVA. CONCLUSIONS: NIV-NAVA allows good synchronization in bi-level NIV in infant cardiac subjects weighing < 5 kg. The analysis of respiratory parameters shows that NIV NAVA decreases the work of breathing more effectively than nasal CPAP. The study shows some typical respiratory patterns in infants. (ClinicalTrials.gov registration NCT01570933.).