Mechanical ventilation results in progressive contractile dysfunction in the diaphragm
Mechanical ventilation results in progressive contractile dysfunction in the diaphragm
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DOI：
10.1152/japplphysiol.00881.2001
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发表时间：
2002-05-01
影响因子：
3.3
通讯作者：
Dodd, SL
中科院分区：
文献类型：
--
作者：
Powers, SK;Shanely, RA;Dodd, SL
这些实验验证了这样的假设，即相对较短的受控机械通气(MV)持续时间将损害横隔膜的最大比力产生(比P-o)，并且随着呼吸机时间的延长，这种力的不足将加剧。为了验证这一假设，将成年SD大鼠随机分为6组：1)对照组(n=12)，2)机械通气12h(n=4)，3)机械通气18h(n=4)，4)麻醉和自主呼吸18h(n=4)，5)机械通气24 h(N 7)，6)麻醉和自主呼吸24 h(n=4)。MV动物麻醉、气管切开、室内空气呼吸。对照组急性麻醉，但不暴露于MV。两个自主呼吸组动物麻醉后自主呼吸18或24 h，对照组和两个自发呼吸组的横隔膜比P-o无显著差异(P>；0.05)。相反，与对照组相比，在刺激频率从15到160赫兹时，所有持续时间的MV都导致隔膜比张力降低(P<；0.05)。机械通气12 h和24 h后，机械通气组的比P-o分别降低了∼18和∼46%(P<；0.05)。这些数据支持这样的假设，即相对短期的机械通气损害了横隔肌的收缩功能，机械通气引起的力缺陷的大小随着呼吸机使用时间的延长而增加。
These experiments tested the hypothesis that a relatively short duration of controlled mechanical ventilation (MV) will impair diaphragmatic maximal specific force generation (specific P-o) and that this force deficit will be exacerbated with increased time on the ventilator. To test this postulate, adult Sprague-Dawley rats were randomly divided into one of six experimental groups: 1) control (n = 12); 2) 12 h of MV (n = 4); 3) 18 h of MV (n = 4); 4) 18 h of anesthesia and spontaneous breathing (n = 4); 5) 24 h of MV (n 7); and 6) 24 h of anesthesia and spontaneous breathing (n 4). MV animals were anesthetized, tracheostomized, and ventilated with room air. Animals in the control group were acutely anesthetized but were not exposed to MV. Animals in two spontaneous breathing groups were anesthetized and breathed spontaneously for either 18 or 24 h. No differences (P > 0.05) existed in diaphragmatic specific P-o between control and the two spontaneous breathing groups. In contrast, compared with control, all durations of MV resulted in a reduction (P < 0.05) in diaphragmatic specific tension at stimulation frequencies ranging from 15 to 160 Hz. Furthermore, the MV-induced decrease in diaphragmatic specific P-o was time dependent, with specific P-o being ∼18 and ∼46% lower (P < 0.05) in animals mechanically ventilated for 12 and 24 h, respectively. These data support the hypothesis that relatively short-term MV impairs diaphragmatic contractile function and that the magnitude of MV-induced force deficit increases with time on the ventilator.