Olson L E, Rodarte J R
J Appl Physiol Respir Environ Exerc Physiol. 1984 Dec;57(6):1710-4. doi: 10.1152/jappl.1984.57.6.1710.
The position of small metallic markers embedded within the lung parenchyma and glued to the pleural surface of four excised right caudal dog lobes were determined during stepwise deflation from an airway opening pressure of 25 cmH2O in air-filled suspended lobes and 8 cmH2O in saline-filled lobes submerged in saline. Changes in the volumes of tetrahedrons formed by four noncoplanar markers were taken as regional lung volume changes at the centroids of the tetrahedron. In both air- and saline-filled lobes at all volumes below total lobe capacity (TLC) there was considerable variability in regional volume. The variability occurred at the first step below TLC and increased with deflation. Regions behaved consistently; regions that were proportionally larger or smaller than the overall lobe at any step tended to be larger or smaller, respectively, at all steps. There was a significant correlation between the regional behavior of the air- and saline-filled lobes. The variability of regional volume did not follow any clear topographical orientation. These results indicate there is considerable variability of lung compliance within small regions. This heterogeneity of regional parenchymal properties may be the anatomical basis of the nonuniformity of regional ventilation known to occur in intact animals and excised lobes within small regions at the same vertical height.
在从气道开口压力25 cmH₂O的充气悬浮肺叶和浸没在盐水中、气道开口压力8 cmH₂O的盐水填充肺叶逐步放气过程中，确定了嵌入四个切除的右尾侧犬肺叶实质内并粘贴在胸膜表面的小金属标记物的位置。由四个不共面标记物形成的四面体体积变化被视为四面体质心处的局部肺体积变化。在所有低于肺叶总容量（TLC）的体积下，充气和盐水填充的肺叶中局部体积都存在相当大的变异性。变异性出现在低于TLC的第一步，并随着放气而增加。各区域表现一致；在任何一步中比整个肺叶成比例地更大或更小的区域，在所有步骤中往往分别更大或更小。充气和盐水填充肺叶的局部行为之间存在显著相关性。局部体积的变异性没有遵循任何明显的地形学方向。这些结果表明，小区域内肺顺应性存在相当大的变异性。区域实质特性的这种异质性可能是已知在完整动物和相同垂直高度小区域内切除的肺叶中发生的区域通气不均匀性的解剖学基础。
