A neuromuscular mechanism maintaining extrathoracic airway patency.
A neuromuscular mechanism maintaining extrathoracic airway patency.
复制标题
维持胸外气道通畅的神经肌肉机制。
DOI：
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发表时间：
1979
期刊：
影响因子：
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通讯作者：
B. Thach
中科院分区：
文献类型：
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作者：
R. Brouillette;B. Thach
研究了兔暴露于负压下时胸外气道（ETA）保持开放的能力。死后，ETA在-6.3 +/- 0.6 cmH2O时塌陷，而在轻度麻醉动物的气道闭塞操作中，它在低至-80 cmH2O的压力下保持通畅。这种差异表明神经肌肉机制维持了ETA的通畅。四项研究结果表明，颏舌肌和颏舌骨肌，向前牵引舌骨和舌骨，有助于维持ETA通畅：1)舌骨前运动增加了死后ETA塌陷的负压，2)闭锁吸气时，第12神经切断术使这些肌肉的肌电活动消失，3)深度麻醉使这些肌肉的活动下降，4)闭锁压力与两块肌肉的综合肌电峰值呈线性相关。第12神经切断术后，ETA闭合压力负性加重，进行性窒息大大超过死后闭合压力，提示其他肌肉也有助于维持ETA通畅。血气紧张、呼吸系统机械感受器和麻醉深度似乎影响颏舌肌和颏舌骨活性。
The ability of the extrathoracic airway (ETA) to remain open when exposed to negative pressure was investigated in rabbits. Postmortem, the ETA collapsed at -6.3 +/- 0.6 cmH2O whereas, during airway occlusion maneuvers in lightly anesthetized animals, it remained patent at pressures as low as -80 cmH2O. This discrepancy suggested that a neuromuscular mechanism maintains ETA patency. Four findings indicated that the genioglossus and geniohyoid muscles, which pull the tongue and hyoid bone anteriorly, help maintain ETA patency: 1) anterior movement of the hyoid bone increased the negative pressure at which the ETA collapsed postmortem, 2) ETA closure during occluded inspirations occurred after 12th nerve section abolished electromyographic activity in these muscles and 3) after deep anesthesia depressed such activity, and 4) closing pressure was linearly related to peak integrated electromyograms of the two muscles. After 12th nerve section, ETA closing pressure became more negative with progressive asphyxia greatly exceeding postmortem closing pressure, which suggests that other muscles also help maintain ETA patency. Blood gas tensions, respiratory system mechanoreceptors, and depth of anesthesia appear to influence genioglossus and geniohyoid activity.