Neurally adjusted ventilatory assist in an infant with chronic lung disease

Abstract

Neurally adjusted ventilatory assist (NAVA) is a mechanical ventilation modality utilizing the electrical activity of the diaphragm (EAdi). EAdi triggers reportedly have significantly shorter delays than other triggers. Patients showing poor synchrony with a ventilator are considered good candidates for NAVA. In a 10-month-old infant with a chronic lung disease, NAVA was useful for improving synchrony with mechanical ventilation. The breathing cycle was very short, as the inspiratory time was 450 msec and the expiratory time was 880 msec as measured by the change in the EAdi. There were a lot of miss-triggering in the flow trigger, as well as a 270 msec trigger delay to the start of inspiration. NAVA improved synchrony with mechanical ventilation by shortening the asynchronous time, which allowed the amount of intravenous sedative to be decreased. The apparent breathing effort of the patient correlated with the EAdi value, which served as a useful index. In the respiratory management of infants with a short respiratory cycle and strong respiratory effort, trigger delay is the main cause of asynchrony. For such patients, NAVA may be useful for improving synchrony with a ventilator.