Frazer D G, Franz G N
Respir Physiol. 1981 Dec;46(3):237-46. doi: 10.1016/0034-5687(81)90124-9.
The amount of gas trapped in excised rat lungs was determined after four inflation-deflation cycles between total lung capacity (TLC) and several end-expiratory volumes or end-expiratory pressures. Lungs ventilated in this way exhibited pressure-volume curves that formed closed loops with varying degrees of hysteresis. The area of these loops was highly correlated with the amount of gas trapped in the lungs. Trapped gas volume and hysteresis increased with deflation to increasingly lower end-expiratory volumes or pressures. The processes responsible for lung hysteresis, however, seem to be primarily dependent upon end-expiratory pressure and only slightly dependent upon end-expiratory volume. A possible explanation of these findings is that menisci, formed in the small airways of the lung during deflation at low lung volumes, are responsible for both the trapped gas and the pressure-volume hysteresis of the lung.
在总肺容量（TLC）与几个呼气末容积或呼气末压力之间进行四个充气-放气循环后，测定切除的大鼠肺中滞留的气体量。以这种方式通气的肺表现出压力-容积曲线，这些曲线形成了具有不同程度滞后现象的闭环。这些环的面积与肺中滞留的气体量高度相关。随着放气至越来越低的呼气末容积或压力，滞留气体量和滞后现象增加。然而，导致肺滞后现象的过程似乎主要取决于呼气末压力，而仅略微取决于呼气末容积。对这些发现的一种可能解释是，在低肺容积放气过程中在肺的小气道中形成的半月板，是导致肺中滞留气体和压力-容积滞后现象的原因。
