油酸型急性呼吸窘迫综合征肺血液流变学变化及其意义探讨

Hemorheologic change in pulmonary circulation blood of oleic acid-induced acute respiratory distress syndrome

目的 探讨肺循环血液流变学在急性呼吸窘迫综合征 (ARDS)发病中的变化及在ARDS肺循环障碍中的可能作用。方法 通过尾静脉注射油酸 (OA)制备大鼠ARDS模型 ,动态检测动物模型 (0 5h ,2h ,6h ,12h ,2 4h ,72h)肺动脉血、颈动脉血和静脉血在不同切变率下的全血粘度 ,同时进行全血细胞分析。结果 OA型ARDS大鼠的肺、体循环血液在高切变率 (2 0 0s-1,30s-1)下的粘度均无明显变化。在低切变率 (5s-1)时 ,6h～ 2 4hARDS大鼠肺循环血全血粘度均显著高于对照组 ;切变率为 1s-1时 ,2hARDS大鼠肺循环血全血粘度即显著升高 ,6h和 12h不仅明显高于对照组 ,也高于自身静脉血 ;体循环血粘度变化不明显。 2h～ 2 4hARDS大鼠肺、体循环血中红细胞和血红蛋白浓度均有增加 ,血小板数则呈减少趋势。结论 OA型ARDS大鼠肺循环血液在低切变率下的粘度增加 ,可通过增加血流阻力和减慢流速 。

Objective To investigate the change of hemorheology in pulmonary circulation and its possible involvement in development and progression of oleic acid(OA)induced acute respiratory distress syndrome(ARDS)Methods In a rat model of OAinduced ARDS,we sequentially measured the whole blood viscosity in pulmonary artery,carotid artery and jugular vein blood at 05h,2h,6h,12h,24h,72h after OA injectionAnd red blood cells(RBC),hemoglobin(Hb)concentration and platelets were also determined at the same timeResults At high rate(200s -1 ,30s -1 ),no changes of whole blood viscosity in pulmonary and systemic circulation were found in OAinduced ARDS ratsAt shear rate 5s -1 ,6h～24h ARDS rats showed a significantly elevated whole blood viscosity in pulmonary circulation than control ratsAt 1s -1 ,the median whole blood viscosity in pulmonary circulation was significantly higher for ARDS rats at 2h post OA injection compared with control rats;and it was not only higher for 6h ARDS group than control but also higher than itself veinsThere were an increased trend for RBC and Hb but decreased trend for platelets in pulmonary and systemic circulation of ARDS rats at various time pointsConclusion These data suggested that the higher whole blood viscosity in pulmonary circulation may contribute to increase pulmonary vascular resistance,block blood flow,and deteriorate hypoxemia in progression of ARDS