EVALUATION OF HUMAN DIAPHRAGM FATIGUE
EVALUATION OF HUMAN DIAPHRAGM FATIGUE
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DOI：
10.1152/jappl.1982.53.5.1196
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发表时间：
1982-01-01
影响因子：
3.3
通讯作者：
GRASSINO, A
中科院分区：
文献类型：
--
作者：
BELLEMARE, F;GRASSINO, A
本文研究了5名正常人在高吸气阻力呼吸时膈肌肌电（EMG）频率成分的时程。计算每次呼吸的高频带（150-350 Hz）（H）和低频带（20-40 Hz）（L）的功率含量之比，并表示为初始呼吸的分数。衰减速率（当存在时）是指数的，并通过测量H/L（TF）的衰减时间常数进行定量。维持吸气时间与总呼吸周期持续时间的比值（TI/Ttot）为0.2 - 1，跨膜压（Pdi）为Pdimax的0.1-0.8。TF与Pdi单调相关。TI/Ttot，遵循双曲线关系。TF与肌电位的传导速度和EMG功率谱的中心频率进行了比较，发现遵循类似的趋势，显示出不同的绝对变化率。TF的值被认为是直接相关的时间一个给定的模式可以持续（Tlim）。EMG变化和Tlim是相关的，并且是由收缩模式引起的代谢变化的表达。
The time course of the frequency content of the electromyogram (EMG) was studied in the diaphragm of 5 normal subjects breating through high inspiratory resistance. The ratio between the power content of a high-frequency band (150-350 Hz) (H) and a low-frequency band (20-40 Hz) (L) was calculated for each breath and expressed as a fraction of the initial breath. The rate of decay (when existent) was exponential and was quantified by measuring the time constant of decay of H/L (TF). Runs were held sustaining the ratio of inspiratory time to total breath cycle duration (TI/Ttot) from 0.2 to 1 and transdiaphragmatic pressure (Pdi) of 0.1-0.8 of Pdimax. TF was monotonically related to Pdi .cntdot. TI/Ttot, following a hyperbolic relationship. TF was compared with velocity of conduction of the myopotentials and with center frequency of the EMG power spectrum and found to follow similar trends showing different absolute rate of change. The values of TF were found to be directly related to the time a given pattern could be sustained (Tlim). EMG changes and Tlim are related and are expressions of the metabolic changes induced by the contraction pattern.