Indicator dilution measurements of extravascular water in the lungs.
Indicator dilution measurements of extravascular water in the lungs.
复制标题
肺部血管外水的指示剂稀释测量。
DOI：
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发表时间：
1969
影响因子：
15.9
通讯作者：
B. E. Wangel
中科院分区：
文献类型：
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作者：
C. Goresky;R. Cronin;B. E. Wangel
在没有肺水肿的情况下，对清醒、休息、运动和麻醉犬进行肺循环多指标稀释研究。将标记红细胞、水和白蛋白一起注入肺动脉，从胸降主动脉获得流出物稀释图。用标记水和红细胞的平均传递时间差与肺水流量的乘积来估计血管外实质水；在死后的检查中，这是用排血肺的含水量的比例来表示的。发现这些比例含水量的估计值随着流量的增加而增加，并接近渐近值。然而，重新考虑毛细血管中的流动模式，得出了这样的假设，即应该计算血管外水，利用一种均匀标记红细胞和血浆中的水的物质作为适当的血管参考，这种物质仅限于循环，而不是仅标记红细胞的示踪剂。这种物质的平均传递时间近似于标记红细胞和白蛋白的平均传递时间之和，每一个都根据该阶段存在的血液含水量的比例加权。这样计算的肺含水量值也随着流量的增加而增加，并且似乎接近于一条渐近线，该渐近线约对应于湿肺重量的三分之二。戊巴比妥麻醉后的水空间估定值与静息清醒动物的较低值相对应。当麻醉的动物也放血时，估计的水空间与之前的值相比不成比例地大。这些实验结果支持肺水空间的稀释估计反映肺毛细血管充盈的假设；这种充盈随着锻炼而增加；充盈的相对增加也是出血反应的一部分。
Multiple indicator dilution studies of the pulmonary circulation were carried out in conscious, resting and exercising, and anesthetized dogs under conditions where there was no pulmonary edema. Labeled red cells, water, and albumin were injected together into the pulmonary artery, and effluent dilution patterns were obtained from the descending thoracic aorta. The product of the mean transit time differences between labeled water and red cells, and the pulmonary water flow was used to estimate extravascular parenchymatous water; and this was expressed as a proportion of the water content of the blood-drained lung at postmortem examination. These estimates of the proportional water content were found to increase with flow, and to approach an asymptotic value. Reconsideration of the flow patterns in capillaries, however, led to the postulate that extravascular water should be calculated, utilizing as the appropriate vascular reference a substance that uniformly labels the water in red cells and plasma, and which is confined to the circulation, rather than a tracer that only labels red cells. The mean transit time of this substance is approximated by the sum of the mean transit times of labeled red cells and albumin, each weighted according to the proportion of the water content of blood present in that phase. The values for lung water content so computed also increased with flow, and appeared to approach an asymptote that corresponded to approximately two-thirds of the wet lung weight. The estimated values for the water space after pentobarbital anesthesia corresponded to the lower values obtained in the resting conscious animals. When the anesthetized animals were also bled, the estimated water space was disproportionately large, in relation to the previous values. These experimental results support the hypothesis that dilutional estimates of the lung water space reflect pulmonary capillary filling; that this filling increases with exercise; and that a relative increase in filling also occurs as part of the response to hemorrhage.