犬单侧肺重度吸入性损伤模型的建立

目的　建立犬单侧肺重度烟雾吸入性损伤模型,观察伤后24h内犬肺组织的变化。　方法　将25只雄性犬随机分为3组:单肺组10只,插入气管导管至左支气管,双肺分离通气,制作单侧肺重度烟雾吸入性损伤模型;双肺组8只,建立普通双肺吸入性损伤模型;对照组7只,不灌烟,其他操作均与单肺组相同。观察3组犬在伤后24h内的存活情况、血流动力学及血气分析指标、肺组织的病理及生理变化。　结果　单肺组和对照组犬伤后24h内全部存活,血流动力学指标稳定, 无全身缺氧表现。双肺组犬伤后24h内死亡5只,存活犬出现呼吸、循环衰竭。单肺组犬伤后24h动脉血氧分压为(65±5)mmHg(1mmHg=0. 133kPa)、混合静脉血氧饱和度0. 64±0. 04,低于对照组而高于双肺组;单肺组犬伤肺的病理形态与传统模型有相似特征并表现出高度的一致性,对侧肺亦出现轻度损伤性病理变化。　结论　本文建立的犬单侧肺重度吸入性损伤模型稳定、可靠,对研究吸入性损伤有重要价值。

Establishment of a canine model of severe smoke inhalation injury on unilateral lung

OBJECTIVE: To establish a canine model of severe smoke inhalation injury on unilateral lung, in order to observe the pathomorphological changes in the injured lung within 24 postburn hours (PBHs). METHODS: Twenty five mongrel dogs were employed in the study and randomized into 3 groups. The left lung was injured by inhaling smoke produced by burning sawdust with sparing the right lung with a breathing tube in 10 dogs in group A. A conventional model of smoke inhalation injury to bilateral lungs was reproduced in 8 dogs in group B, and dogs in group C not subjected to smoke inhalation served as controls. Hemodynamic changes, blood gas analysis and the pathophysiologic changes in the lungs were observed within 24 PBHs. RESULTS: All of the dogs in groups A and C survived. Hemodynamic indices in the dogs in groups A and C remained stable without showing signs of systemic hypoxia. The arterial oxygen partial pressure in dogs of group A was 65 +/- 5 mm Hg, and the oxygen saturation in the mixed blood was 0.64 +/- 0.04 at 24 PBHs, and they were much lower than those in group C but higher than those in group B. The pathological changes in the injured side of the lungs in group A were similar to those in group B with high consistency, and the changes, though milder, could also be identified in the contralateral uninjured lung. Five dogs died in the group B within 24 hours after smoke inhalation and the survivors showed signs of multiple organ failure. CONCLUSION: The canine model of acute severe unilateral pulmonary smoke inhalation injury was reproduced reliably, and could be an ideal model for the study on smoke inhalation injury.