机械通气条件下以内毒素建立急性肺损伤兔模型

Establishment of Acute Lung Injury Model by Injection of Endotoxin under Mechanical Ventilation in Rabbit

为建立脓毒性急性肺损伤（ＡＬＩ）模型，给新西兰兔静脉注射内毒素０．１ｍｇ／ｋｇ，在机械通气条件下观察肺氧合等肺功能损害的进程。结果：在注射内毒素后早期肺损害不明显，注射后８ｈ出现显著的损害，１４ｈ达到ＡＬＩ标准，支气管肺泡灌洗液分析及肺形态学出现显著异常。结果表明用本法可诱导稳定的脓毒性ＡＬＩ兔模型，供ＡＬＩ病理生理机制及治疗方法研究之用。

To establish acute lung injury model, New Zealand White rabbits were divided int o model group (n=13) and control group (normal group, n= 5). The animals in the model group were injected intravenously with Escherichia coli lipopolys accharide (LPS) 0.1mg/kg (pretreated with one tenth of the total dose 12h before ). Gas change, lung mechanics, blood pressure and pulse were monito red under mechanical ventilation. The lung injury was observed 8h aft er the second injection of LPS. The measurement values for PaO 2/FiO 2, alveol ararte rial O 2 gradient (AaDO 2), intrapulmonary shunting (Qs/Qt), Cdyn and Rr s showed that the pulmonary function in the model group was significantly worse than that before the second injection of LPS and that in the control group (P<0.01 ). In the model group, PaO 2/FiO 2 was below 40kPa, atelectasis, edema, hemorr age and inflammatory infiltrates were also seen in the lung sections 14h after t he 2nd injection of LPS, white blood cell count and total protein (TP) content w ere sign ificantly increased in BALF, and wet/dry weight ratio of the lung was also signi ficantly increased. It is concluded that acute lung injury model has been establ ished within 8～14h by injection of endotoxin intravenously based on impaired ga s change, lung mechanics, and increased blood cell count and TP content in BALF.