INCREASED MICROVASCULAR PERMEABILITY IN DOG LUNGS DUE TO HIGH PEAK AIRWAY PRESSURES
INCREASED MICROVASCULAR PERMEABILITY IN DOG LUNGS DUE TO HIGH PEAK AIRWAY PRESSURES
复制标题
DOI：
10.1152/jappl.1984.57.6.1809
复制
发表时间：
1984-01-01
影响因子：
3.3
通讯作者：
THIGPEN, J
中科院分区：
文献类型：
--
作者：
PARKER, JC;TOWNSLEY, MI;THIGPEN, J
在离体犬肺下叶血液灌注模型中，测定了气道峰压（Paw）对血管通透性的影响以及抗水肿形成的安全系数。使用测得的滤过系数（Kf，C）、等重毛细血管压（Pc，i）和组织安全系数耗尽的临界毛细血管压（Pcrit）评价微血管渗透性。气道压力保持恒定在3 cmH 2 O，除了20 min的测试期，此时肺以6/min通气，具有足够的体积以产生范围为5至60 cmH 2 O的峰值充气压力。平均Kf，C（单位：ml. cnt. dot.）min-1. cmH2O. cntdot. 100 g-1）在峰值气道压力之前和之后立即测量。当Paw超过42 cmH 2 O时，所有肺的Kf，C均显著增加，但在较低Paw时，仅2个实验中Kf，C显著增加。在45-55和55-65 cmH 2 O Paw组中，平均Pc，i与对照组相比显著降低，Pc，i和Pcrit与Paw通气后测量的Kf，C呈负相关。这些数据表明，通气与Paw高于42 cmH 2 O（30.9托），在某些情况下，较低的压力为20分钟显着增加毛细血管导水率，降低血浆蛋白质在毛细血管壁的有效渗透作用，并降低总的组织安全系数对水肿的形成。
The effect of peak airway pressure (Paw) on vascular permeability and the safety factor against edema formation was determined in isolated blood-perfused lower lobes of dog lungs. Microvascular permeability was evaluated using the measured filtration coefficient (Kf,C), isogravimetric capillary pressure (Pc,i) and critical capillary pressure (Pcrit) for exhaustion of tissue safety factors. Airway pressure was maintained constant at 3 cmH2O except for the test period of 20 min when the lungs were ventilated at 6/min with sufficient volume to generate a peak inflation pressure ranging from 5 to 60 cmH2O. Mean Kf,C (in ml .cntdot. min-1 .cntdot. cmH2O .cntdot. 100 g-1) were measured before and immediately after the period of peak airway pressures. Kf,C was significantly increased in all lungs where Paw exceeded 42 cmH2O, but in only 2 experiments at a lower Paw. Mean Pc,i was significantly reduced from control in the 45-55 and 55-65 cmH2O Paw groups, and both Pc,i and Pcrit were inversely related to Kf,C measured after Paw ventilation. These data indicate that ventilation with Paw above 42 cmH2O (30.9 Torr) and in some cases lower pressures for 20 min significantly increased capillary hydraulic conductivity, reduced the effective osmotic effect of plasma proteins at the capillary wall, and reduced the total tissue safety factor against edema formation.