ROLE OF PULMONARY SURFACTANT IN AIRWAY-CLOSURE - A COMPUTATIONAL STUDY
ROLE OF PULMONARY SURFACTANT IN AIRWAY-CLOSURE - A COMPUTATIONAL STUDY
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DOI：
10.1152/jappl.1993.75.3.1323
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发表时间：
1993-09-01
影响因子：
3.3
通讯作者：
KAMM, RD
中科院分区：
文献类型：
--
作者：
OTIS, DR;JOHNSON, M;KAMM, RD
建立了模拟呼气过程中液体搭桥关闭呼吸道的数值模型。模型考虑了表面活性剂和时变几何形状的影响，确定了由表面张力(Rayleigh)不稳定引起的液层流动，计算跟踪了膜的发展到闭合、屈服压力、速度、表面形状和表面活性剂浓度分布。结果表明，表面活性剂通过降低平均表面张力和表面张力梯度的作用，有效地延缓或消除了液桥现象。前一种效应在最小化液体层中负压的大小方面也是关键的，因此可能在减少气道顺应性坍塌的倾向方面也是关键的。
A numerical model that simulates airway closure by liquid bridging during expiration has been developed. The effects of both surfactant and time-varying geometry have been included; the model determines the liquid layer flow resulting from a surface tension (Rayleigh) instability, and the computation traces the film's development to closure, yielding pressure, velocity, surface shape, and surfactant concentration distributions. It is found that surfactant is effective in retarding or eliminating liquid bridging through the reduction of the mean surface tension and the action of surface tension gradients. The former effect is also critical in minimizing the magnitude of the negative pressure in the liquid layer and thus presumably in reducing the tendency for airway compliant collapse.