Comparison of neurally-adjusted ventilator assist in infants before and after extubation

BACKGROUND: To compare invasive (iNAVA) and non-invasive (nivNAVA) neurally adjusted ventilatory assist in infants, respect to gas exchange, breathing pattern, respiratory drive, infant-ventilator interaction and synchrony, vital parameters and required sedation. METHODS: Ten consecutive intubated term infants admitted for respiratory failure of different etiology underwent to 2-hour not-randomized trials of iNAVAand, after extubation, nivNAVA, the latter with unchanged ventilator settings and with air-leaks compensating software. Arterialized capillary blood was sampled at the end of each trial. We computed: 1) the minimum (EA_dimin) and peak (EA_dipeak) values of the diaphragm electrical activity; 2) ventilator (RR_mec) and own patients' (RR_neu) respiratory rates; 3) inspiratory (delay_TR-insp) and expiratory trigger delays (delay_TR-expM) and the time of synchrony between patient's effort and ventilator assistance (Time_synch/T_ineu); 4) the asynchrony index. Vital parameters and required sedation were also recorded. RESULTS: iNAVAand nivNAVAdid not differ between in terms of gas exchange (pH (7.35 [7.31-7.41] vs. 7.36 [7.30-7.40], P=0.745), PcCO₂ (38.4 [34.8-42.6] vs. 36.9 [33.9-41.6] mmHg, P=0.469) and PcO₂/FiO₂ (211 [168-323] vs. 214 [189-282], P=0.195), respectively). EAdi_min, EAdi_peak, RR_mec and RR_neu were similar before and after extubation. Both modes confirmed an optimal infant-ventilator interaction (i.e. delay_TR-insp, delay_TR-exp and Time_synch/Ti_neu), irrespective of the interface, and no patients showed clinical relevant asynchronies. Alow requirement of sedation with fentanyl was recorded during both trials, without differences between. CONCLUSIONS: We found iNAVAand nivNAVAto be characterized by similar gas exchange, breathing pattern, respiratory drive, infant-ventilator interaction and synchrony, vital parameters and required sedation.