[吸入麻醉下心输出量变化对氧合及肺内短路（Qs/Qt）的影响]

[Effect of changes in cardiac output on oxygenation and intrapulmonary short circuit (Qs/Qt) under inhalation anesthesia].

作者信息

Solares G, Qualls C

机构信息

Departamento de Anestesia y Reanimación, Hospital Universitario Marqués de Valdecilla, Santander.

出版信息

Rev Esp Anestesiol Reanim. 1994 Jul-Aug;41(4):200-4.

PMID:7938856

Abstract

OBJECTIVES

To assess the relation between changes in pulmonary shunt and minute volume induced by blood loss, using an animal model with anesthetic maintenance by isoflurane CAM 1.

MATERIAL AND METHODS

Eight dogs were given balanced anesthesia with pancuronium and isoflurane. Variables monitored were systemic and pulmonary arterial pressures, central venous and pulmonary capillary pressures and minute volume. Arterial and mixed venous blood gas measurements were taken from the pulmonary artery catheter, and blood samples were analyzed for hemoglobin in order to calculate pulmonary shunt (Qs/Qt). Two levels or stages of hypovolemia were studied: a) level I = loss of 20% blood volume and b) level II = loss of 30%.

RESULTS

A significant decrease of 35% (139 +/- 43 to 90 +/- 24 ml/min-1/kg-1; p < 0.001) in minute volume was observed at the first level of hypovolemia; a 52% (139 +/- 43 to 69 +/- 23 ml/min-1/kg-1; p < 0.001) decrease was found at the second. This decrease was accompanied by similar drops in Qs/Qt of 34% (18.2 +/- 5% to 12.1 +/- 5%; p < 0.01) and 47% (18.2 +/- 5% to 9.2 +/- 5%; p < 0.01) at the first and second levels, respectively. Linear regression analysis showed a direct relation between changes in Qs/Qt with changes in minute volume.

CONCLUSIONS

The data reported in this study indicate that changes in Qs/Qt are directly related to those of minute volume in the presence of isoflurane.

摘要

目的

使用异氟烷CAM 1维持麻醉的动物模型，评估失血引起的肺分流和分钟通气量变化之间的关系。

材料与方法

八只犬接受泮库溴铵和异氟烷平衡麻醉。监测的变量包括体循环和肺动脉压、中心静脉压和肺毛细血管压以及分钟通气量。从肺动脉导管采集动脉血和混合静脉血进行血气分析，并分析血样中的血红蛋白以计算肺分流（Qs/Qt）。研究了两个低血容量水平或阶段：a）I级 = 失血20%，b）II级 = 失血30%。

结果

在第一个低血容量水平时，观察到分钟通气量显著下降35%（从139±43降至90±24 ml/min-1/kg-1；p < 0.001）；在第二个水平时下降了52%（从139±43降至69±23 ml/min-1/kg-1；p < 0.001）。这种下降分别伴随着Qs/Qt在第一个和第二个水平时相似的下降，即34%（从18.2±5%降至12.1±5%；p < 0.01）和47%（从18.2±5%降至9.2±5%；p < 0.01）。线性回归分析显示Qs/Qt的变化与分钟通气量的变化呈直接关系。