呼吸机相关肺损伤模型建构的最佳潮气量

目的:应用大潮气量机械通气探讨制作兔的呼吸机相关肺损伤模型的最佳潮气量。方法:根据黄金分割法原理,采用三种不同潮气量68mL/kg、60mL/kg和45mL/kg各持续通气1分钟造成兔的急性肺损伤,取0h,12h,24h,48h四个时间点进行观察,观察兔存活情况,计算各时间点肺湿/干重比观察肺水肿严重程度及变化,组织病理学切片观察各时间点肺组织形态学改变。结果:1、潮气量68mL/kg组、60mL/kg组和45mL/kg组兔48h存活率分别为58.33%(7/12)、91.67%(11/12)和100%(12/12);与正常对照组相比,三组肺湿/干重比在0小时无明显变化,12小时明显增高,在24小时时达峰值,48小时后降低。3、镜下观察机械通气后不同时间肺组织均有不同程度形态学改变,68mL/kg组肺组织形态学改变非常明显,60mL/kg组肺组织形态学改变明显,45mL/kg组肺组织形态学改变不明显。结论:大潮气量通气成功建立兔的呼吸机相关肺损伤实验动物模型,潮气量指标为60mL/kg。

The best tidal volume to construct the ventilator-associated lung injury experimental animal model

Objective:To approach the best tidal volume of applying high tidal volume ventilation to constructing the ventilator associated lung injury(VALI)experimental animal model of rabbits.Methods:Three tidal volume(68mL/kg,60mL/kg and 45mL/kg)were used into rabbits keeping on venting for one minute to induce acute lung injury.Survival rates of the rabbits were observed at differ-ent time(0h,12h,24h,48h respectively)after ventilation;edema of lung by calculating lung W/D;the changesof lung tissue by HE stain-ing .Results:The survival rates of group with 68mL/kg, 60mL/kg and 45mL/kg were 58.33%(7/12), 91.67%(11/12)and 100%(12/12)respectively at 48h.Compared with normal control group,lung W/D of group 68mL/kg,60mL/kg and 45mL/kg showed no change at 0 hour, obviously increased at 12 hours, reached peak at 24 hours, subsequently decreased at 48 hours.HE staining showed that the changes of lung tissues were extremely obvious, obvious, not obvious in the group with 68mL/kg, 60mL/kg and 45mL/kg respectively.Conclusion:The best VILI experimental animal model of rabbits was established successfully after high tidal volume ventilation, and in-dex of tidal volume was 60mL/kg.