Hauge A, Nicolaysen G
Acta Physiol Scand. 1980 Jul;109(3):325-32. doi: 10.1111/j.1748-1716.1980.tb06603.x.
The importance of the perfusion pattern for the oxygen transfer has been examined in isolated rabbit lungs perfused with plasma at constant volume inflow. The lungs were ventilated with constant tidal volume and constant end-expiratory pressure. Following a standardized rise in FIO2 the rate of rise in pulmonary venous PO2 (delta PO2/delta t) was measured during alternately pulsatile and non-pulsatile perfusion in normal lungs and in lungs made edematous by elevation of left atrial pressure. In normal lungs there was no difference in delta PO2/delta t when the two modes of perfusion were compared. In edematous lungs delta PO/delta t was statistically higher during pulsatile perfusion, indicating a beneficial effect of flow- and pressure pulsations, e.g. a better distribution of V/Q ratios throughout the lungs. In a separate series of expts. the advancement of a high O2 front through the airways was measured, and the two perfusion patterns compared. Since no difference was found, we suggest that the phenomenon of "cardiogenic gas mixing" in the airways in vivo is a result of a direct action of the heart on the lungs rather than arterial pulsations.
在以恒定体积流入量用血浆灌注的离体兔肺中，已研究了灌注模式对氧转运的重要性。肺以恒定潮气量和恒定呼气末压力进行通气。在标准化的吸入氧分数（FIO2）升高后，在正常肺以及因左心房压力升高而产生水肿的肺中，交替进行搏动性灌注和非搏动性灌注时，测量肺静脉血氧分压（PO2）的上升速率（δPO2/δt）。在正常肺中，比较两种灌注模式时，δPO2/δt没有差异。在水肿肺中，搏动性灌注期间的δPO/δt在统计学上更高，表明血流和压力搏动具有有益作用，例如在整个肺中通气/血流比值（V/Q）分布更佳。在另一系列实验中，测量了高氧前沿在气道中的推进情况，并比较了两种灌注模式。由于未发现差异，我们认为体内气道中“心源性气体混合”现象是心脏对肺的直接作用而非动脉搏动的结果。
