油酸制作ARDS犬模型及CT表现

Acute respiratory distress syndrome(ARDS)model in dogs induced by oleid acid and its CT features

目的:探索利用油酸制作犬急性呼吸窘迫综合征(ARDS)模型的方法及CT评价犬ARDS的价值。方法:将16条健康比格犬随机分为模型组(A组,12条)和对照组(B组,4条),A组在30min内从深静脉缓慢注入0.18mL/kg油酸(用0.9%生理盐水30mL稀释)造模,当犬动脉血氧分压(PaO2)/吸入氧分数值(FiO2)≤200mmHg和肺动脉楔压(PCWP)≤18mmHg时,即认定犬ARDS成模;B组仅从深静脉注入相同容量的0.9%生理盐水。两组在造模前及造模后均行CT扫描。在CT扫描结束后对犬实施安乐死,取出肺组织观察大体标本及镜下情况,并计算肺湿干比重(W/D)。结果:A组在油酸注射(90±10)min后形成ARDS模型,其肺湿干比重为10.42±0.74,与B组(5.33±0.75)比较差异有统计学意义(P<0.05);犬ARDS镜下表现为肺水肿、炎性细胞渗出及透明膜形成,而两肺弥漫分布磨玻璃密度影则为犬ARDS的典型CT表现。结论:利用油酸能较好地制作犬ARDS模型,CT能有效监测犬ARDS的形成。

Objective To investigate the way of producing acute respiratory distress syndrome （ARDS） model of dogs by oleic acid （OA） and to assess the value of CT in monitoring ARDS model of dogs. Methods： 16 healthy Beagle dogs were randomly divided into the model group（group A, n= 12） and the control group（group B, n=4）, Acute lung injury （group A） was induced by the infusion of 0.18 ml/kg OA （diluted in 30 ml of 0.9% saline） slowly through the central venous catheter in 30rain and ARDS was identified while PaO2/ FiO2≤200mmHg and PCWP≤18mmHg. Group B was only infused with the same volume of 0.9% saline. Thorax CT scans were performed before and after modeling in the two groups and dogs were euthanized after CT scans. The lung tissue was removed for gross specimen and microscopic examination. At the same time, lung wet-dry weight ratio （W/D） was calculated. Results：ARDS was formed in （90± 10）min after injection of OA. The lung wet to dry ratio of group A was 10.42±0.74 and there was statistical difference （P〈0.05） between group A and group B. The pathological changes of ARDS included pulmonary edema, inflammatory cell exudation and hyaline mem- brane formation. The diffuse distribution of ground-glass opacity in two lungs was the typical CT findings of ARDS in dogs. Conclusion..ARDS model of dogs can be produced by oleic acid and CT can effectively monitor the formation of ARDS in dogs.