Neurally triggered breaths have reduced response time, work of breathing, and asynchrony compared with pneumatically triggered breaths in a recovering animal model of lung injury

Abstract

Neurally triggered breaths have reduced asynchrony, trigger delay, and pressure time product, which may indicate reduced work of breathing associated with less effort to trigger the ventilator and faster response to effort. Further study is required to demonstrate if these differences will lead to decreased days of ventilation and less use of sedation in patients.

Neurally adjusted ventilator assist (NAVA) reduces asynchrony during non-invasive ventilation for severe bronchiolitis

“…Reductions in these asynchronies seems to be less important in other studies compared to reductions in the three main asynchronies . Flow asynchronies, defined as a mismatch between the ventilator flow and the patient flow were reported in animals during NAVA . We did not analyze this type of asynchrony in our study.…”

“…13,15,17 Flow asynchronies, defined as a mismatch between the ventilator flow and the patient flow were reported in animals during NAVA. 30 We did not analyze this type of asynchrony in our study.…”

“…We did not measure indices of work of breathing but as suggested in previous studies, the reduction of the trigger delay leads to a decrease in the work needed to activate an assist. 22,30 For several years, the use of NIV in bronchiolitis has dramatically increased in European countries 10,31,32 and in Australia, 33 and it is now the primary ventilatory support in our unit as reported in 2008. 7 In accordance with our practice, in situations of nCPAP failure, NIV is attempted in order to avoid intubation.…”

“…This benefit may be the same in children with bronchiolitis and may explain a part of the reduction of trigger delay. We did not measure indices of work of breathing but as suggested in previous studies, the reduction of the trigger delay leads to a decrease in the work needed to activate an assist …”

Mechanical Ventilation

“…In a recent animal study performed in young pigs recovering from lung injury, we found that when animals were healthy, the incidence of asynchrony occurred in 8 % of pneumatically triggered inflation (Heulitt 2012). When inflation were triggered via a neural signal from an EMG signal from the diaphragm, asynchrony was still low at 6 % of inflation.…”