McFarlane P A, Gardaz J P, Sykes M K
J Appl Physiol Respir Environ Exerc Physiol. 1984 Sep;57(3):739-43. doi: 10.1152/jappl.1984.57.3.739.
Left lower lobe-to-total blood flow ratio (Ql/QT) was measured with electromagnetic flow probes in anesthetized open-chest dogs. There was a 66% reduction in Ql/QT during lobar collapse, a 53% reduction during lobar ventilation hypoxia with pulmonary venous PO2 and PCO2 equal to mixed venous tensions, and a 45% reduction during a similar degree of ventilation hypoxia but with normal end-tidal PCO2. We concluded that the reduction in blood flow during lobar collapse is due predominantly to hypoxic vasoconstriction, but that this mechanism is augmented by the raised PCO2 and mechanical factors present during collapse.
使用电磁血流探头在麻醉开胸犬中测量左下叶与总血流量之比（Ql/QT）。肺叶萎陷时Ql/QT降低66%，肺叶通气性低氧且肺静脉PO2和PCO2等于混合静脉张力时降低53%，在类似程度的通气性低氧但呼气末PCO2正常时降低45%。我们得出结论，肺叶萎陷期间血流量的减少主要归因于低氧性血管收缩，但这种机制会因萎陷期间PCO2升高和机械因素而增强。
