Effects of dextran 70 on hemodynamics and lung liquid and protein exchange in awake sheep.
Effects of dextran 70 on hemodynamics and lung liquid and protein exchange in awake sheep.
复制标题
右旋糖酐 70 对清醒羊血流动力学、肺液体和蛋白质交换的影响。
DOI：
10.1161/01.res.67.4.852
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发表时间：
1990
影响因子：
20.1
通讯作者：
Staub,NC
中科院分区：
文献类型：
--
作者：
Arakawa,M;Jerome,EH;Enzan,K;Grady,M;Staub,NC
我们研究了静脉输注右旋糖酐70对肺液体和蛋白质交换的影响，以确定其影响是否是由于血流动力学改变或微血管通透性改变。在六只患有慢性肺淋巴瘘的清醒绵羊中，我们进行了三个实验：1）对照，2）30分钟输注1升6%右旋糖酐70，3）输注1升0.9% NaCl。除了肺血流动力学和淋巴动力学，我们还测量了[125 I]白蛋白的血浆-肺淋巴平衡率。我们跟踪所有的羊10个小时，包括2个小时的基线期。在30分钟输注结束时，右旋糖酐在扩大血浆容量方面（63 +/- 15% [平均值+/- SD]）比生理盐水（11 +/- 6%）更有效。右旋糖酐后肺血管压力增加，并保持升高8小时，而生理盐水后，压力在1小时内恢复到基线。右旋糖酐后，肺淋巴流量增加并保持升高。仅在生理盐水给药后一过性升高。我们证实，右旋糖酐与肺淋巴液迅速平衡（半衰期，小于0.6小时），即使它维持了全身血浆体积扩张（半衰期，11.1 +/- 2.7小时）。右旋糖酐增加血浆和淋巴总大分子渗透压，但不增加肺中的血浆-间质（淋巴）渗透压差，除了在输注期间短暂增加。淋巴/血浆蛋白浓度比增加后，右旋糖酐主要是由于血浆蛋白稀释。血浆和肺淋巴液之间示踪白蛋白平衡的半衰期没有差异（对照，2.2 +/- 0.6小时;生理盐水，2.0 +/- 0.6小时;右旋糖酐，2.3 +/- 0.6小时）。右旋糖酐70主要通过增加微血管压力和可能的过滤表面积来增加液体过滤。没有证据表明肺微血管屏障对白蛋白的渗漏发生变化。
We studied the effect of intravenous dextran 70 infusion on lung liquid and protein exchange to determine whether its effects were due to altered hemodynamics or to altered microvascular permeability. In each of six instrumented awake sheep with chronic lung lymph fistulas, we performed three experiments: 1) control, 2) a 30-minute infusion of 1 l of 6% dextran 70, and 3) an infusion of 1 l of 0.9% NaCl. In addition to pulmonary hemodynamics and lymph dynamics, we measured the plasma-to-lung lymph equilibration rate of [125I] albumin. We followed all the sheep for 10 hours, including a 2-hour baseline period. Dextran was more effective in expanding plasma volume (63 +/- 15% [mean +/- SD]) than saline (11 +/- 6%) at the end of the 30-minute infusion. Pulmonary vascular pressures increased after dextran and remained elevated for 8 hours, whereas after saline the pressures returned to baseline within 1 hour. After dextran, lung lymph flow increased and remained elevated. It was only transiently increased after saline. We confirmed that dextran equilibrated rapidly with lung lymph (half-time, less than 0.6 hour), even though it maintained plasma volume expansion for the whole body (half-time, 11.1 +/- 2.7 hours). The dextran increased both plasma and lymph total macromolecular osmotic pressure but did not increase the plasma-interstitial (lymph) osmotic pressure difference in the lung, except transiently during the infusion. The lymph/plasma protein concentration ratio increased after dextran due mainly to plasma protein dilution. There were no differences in the half-time of tracer albumin equilibration between plasma and lung lymph (control, 2.2 +/- 0.6 hours; saline, 2.0 +/- 0.6 hours; dextran, 2.3 +/- 0.6 hours). Dextran 70 increased liquid filtration mainly by increasing microvascular pressure and possibly filtration surface area. There was no evidence for a change in the leakiness of the lung microvascular barrier to albumin.