Airway reopening pressure in isolated rat lungs.
Airway reopening pressure in isolated rat lungs.
复制标题
离体大鼠肺部气道重新开放压力。
DOI：
10.1152/jappl.1994.76.3.1372
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Samsel,RW
中科院分区：
文献类型：
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作者：
Naureckas,ET;Dawson,CA;Gerber,BS;Gaver3rd,DP;Gerber,HL;Linehan,JH;Solway,J;Samsel,RW
在先前的模型研究中，我们根据关系P殖利率=8.3伽马/R预测了气道重新开放的屈服压力(P Year)应取决于气道液体表面张力(GAMA)和气道半径(R)。为了验证这一预测，我们用微焦点X射线成像技术研究了三只大鼠离体肺的钽支气管图。在气管塌陷和重新充气时，记录到了32条直径从300微米到2400微米的气管。将气道压力瞬时降至-40 cmH2O以关闭气道。然后将气道压力从0缓慢增加到25cmH2O。在每个气道中，观察到的直径保持不变，直到达到屈服值；在这个压力下，可以看到气道“突然”打开，从而可以清楚地识别出气道重新开放的压力。当P产额与最大充气时的直径作图时，实验数据与假设伽马为35达因/厘米的P产额的预测大致一致。测量值与预测值的密切一致表明，表面活性物质存在于这些呼吸道中，并有助于呼吸道的重新开放。
In a previous modeling study, we predicted that the yield pressure for airway reopening (Pyield) should depend on airway fluid surface tension (gamma) and airway radius (R), according to the relationship Pyield = 8.3 gamma/R. To test this prediction, we studied tantalum bronchograms of isolated perfused rat lungs from three rats by using microfocal X-ray imaging. Thirty-two airways with diameters ranging from 300 to 2,400 microns were recorded as the airways were collapsed and reinflated. Airway pressure was reduced transiently to -40 cmH2O to produce airway closure. Airway pressure was then slowly increased from 0 to 25 cmH2O. In each airway, the observed diameter remained constant until a Pyield was reached; at this pressure, airways were seen to “pop” open, allowing clear identification of airway reopening pressure. When Pyield was plotted against diameter at maximum inflation, the experimental data were in approximate agreement with predictions of Pyield made assuming a gamma of 35 dyn/cm. The close correspondence of the measured values with these predictions suggests that surfactant is present in these airways and facilitates airway reopening.