Huang Dong-ya, Huang Ying-zi, Wu Xiao-yan, Liu Huo-gen, Yang Yi, Qiu Hai-bo
Department of Critical Care Medicine, Nanjing Zhongda Hospital, Southeast University, Nanjing 210009, China.
Zhonghua Yi Xue Za Zhi. 2011 May 24;91(19):1348-52.
To observe the effects of neurally adjusted ventilatory assist (NAVA) on subject-ventilator synchrony in rabbits with acute respiratory distress syndrome (ARDS).
The rabbit model of ARDS was induced by intratracheal infusion of hydrochloric acid. After sufficient recruitment, the rabbits were randomly divided into 2 groups: pressure support ventilation (PSV) group and NAVA group. The parameters of subject-ventilator synchrony such as ventilation trigger, ventilation switching and magnitude of assist were observed at 0, 1, 2, 3 h respectively.
(1) Ventilation trigger: 1) trigger delay: the trigger delay in the NAVA group were markedly lower than the PSV group at 0, 1, 2, 3 h (P < 0.05); as ventilation time elapsed, the trigger delay changed neither in NAVA nor in PSV group (P > 0.05). 2) Ineffective trigger index: the ineffective trigger index was 17.7% ± 13.7% in the PSV group. While all neural efforts were trigger, there was no ineffective trigger observed in the NAVA group. (2) Off-cycle delay: the off-cycle delay were significantly lower in the PSV group than that in the NAVA group at 0, 1, 2, 3 h (P < 0.05); as the ventilation time elapsed, the off-cycle delay changed neither in the NAVA group nor in the PSV group (P > 0.05). (3) Magnitude of assist: in the NAVA group, peak EAdi and peak pressure were markedly correlated (determination coefficient 0.86 ± 0.07, P < 0.05). But pressure delivery during the PSV group was not correlated with EAdi (P > 0.05).
As compared with PSV, NAVA can improve subject-ventilator synchrony in rabbits with ARDS.
观察神经调节通气辅助（NAVA）对急性呼吸窘迫综合征（ARDS）兔的人机同步性的影响。
通过气管内注入盐酸诱导兔ARDS模型。充分复张后，将兔随机分为2组：压力支持通气（PSV）组和NAVA组。分别在0、1、2、3小时观察人机同步性参数，如通气触发、通气切换和辅助幅度。
（1）通气触发：1）触发延迟：NAVA组在0、1、2、3小时的触发延迟明显低于PSV组（P<0.05）；随着通气时间的延长，NAVA组和PSV组的触发延迟均无变化（P>0.05）。2）无效触发指数：PSV组的无效触发指数为17.7%±13.7%。而在NAVA组，所有神经驱动均能触发通气，未观察到无效触发。（2）脱机延迟：PSV组在0、1、2、3小时的脱机延迟明显低于NAVA组（P<0.05）；随着通气时间的延长，NAVA组和PSV组的脱机延迟均无变化（P>0.05）。（3）辅助幅度：在NAVA组，EAdi峰值与峰值压力显著相关（决定系数0.86±0.07，P<0.05）。但PSV组的压力输送与EAdi无关（P>0.05）。
与PSV相比，NAVA可改善ARDS兔的人机同步性。
