[Effect of non-invasive NAVA on the patients with acute exacerbation of chronic obstructive pulmonary disease].

Objective: To observe the effect of non-invasive neurally adjusted ventilatory assist (NIV-NAVA) on patient-ventilator synchrony and effect of gas exchange in patients with acute exacerbation of chronic obstructive pulmonary disease compared with NIV-pressure support ventilation (PSV). Methods: This was a prospective study of 40 patients with AECOPD given 30-min trials of NIV with NIV-PSV group (n=20) and NAVA group (n=20) in random order. Arterial blood gas analysis (ABGs), main asynchrony events and asynchrony index were quantified. Results: There were no significant difference between the two groups on effect of gas exchange (P>0.05). Main asynchrony events during NIV-NAVA including autotriggering, ineffective efforts and double triggering were less frequent than NIV-PSV (P<0.05). The trigger delay in the NIV-NAVA group was markedly shorter than the NIV-PSV (62.20±8.91 vs 112.65±15.10)ms (P<0.001). The inspiratory/expiratory off-cycle delay was significantly shorter in the NIV-PSV group than that in the NIV-NAVA group (73.00±18.27 vs 187.95±39.24)ms (P<0.001). The occurrence of severe asynchrony (AI>10%) was also less under NAVA (P<0.05). Conclusions: Both NIV-NAVA and NIV-PSV can improve gas exchange. As compared with NIV-PSV, NIV-NAVA can reduce main asynchrony events, improve patient-ventilator synchrony in patients with AECOPD.