The Effectiveness Of Neurally Adjusted Ventilatory Assist On Improving Patient-ventilator Synchrony:A Meta-analysis

Objective:To systematically review the impact of neurally adjusted ventilatory assist(NAVA)on shortening trigger delay and cycling-off delay to confirm whether the new mode can be more effective on improving patient-ventilator synchrony of mechanical ventilation than conventional modes or not.The outcome of the Meta-analysis will provide an evidence for respiratory care nurses to choose an effective and comfortable mode for the patients.Methods:The original studies about NAVA versus conventional modes in trigger delay or cycling-off delay were retrieved based on Chinese and foreign digital databases.Data was searched and extracted,and methodological quality of all included studies was assessed by 2 reviewers independently.RevMan5.3 was then used to perform Meta-analysis.Results:Totally 13 original studies were included.12 of them used trigger delay to evaluate the effect of NAVA,the result of the Meta-analysis:SMD(-1.92),95%CI(-2.50,-1.34);8 of them used cycling-off delay to evaluate the effect of NAVA,the result of the Meta-analysis:SMD(-2.27),95%CI(-3.35,-1.20).These two results showed that compared with control,NAVA had significantly shortened trigger delay and cycling-off delay(P<0.01).Differences among included studies in characteristics of these patients may produce a lot of heterogeneity.The other secondary outcomes of patient-ventilator synchrony had not been evaluated because the sample sizes of them were too small to be performed Meta-analysis.Conclusions:In the Meta-analysis,13 original studies about the impact of NAVA on trigger delay and cycling-off delay were included after comprehensive collection,strict evaluation and selection.The results of these studies showed that compared with the conventional modes which trigger and cycle through monitoring airway pressure or flow,NAVA can shorten trigger delay and cycling-off delay to improve patient-ventilator synchrony significantly,enhance the tolerance of patients,maintain the curative effect and comfort of mechanical ventilation.