Feasibility study on neurally adjusted ventilatory assist in noninvasive ventilation after cardiac surgery in infants

Abstract

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 < 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.