摘要
目的 探求急性肺损伤 (ALI)动物模型在高CO2 通气时病理生理指标的改变机制。方法 2 2只新西兰大白兔随机分为对照组 (C组 )、非高CO2 通气组 (N组 )、高CO2 (8% )通气组 (H组 )。N组和H组通过静脉注射油酸 (0 1ml/kg)复制ALI模型。 3组均机械通气至 3h ,观察生理及病理指标的变化。结果 H组气道峰压显著低于N组 ,动态胸肺顺应性显著高于N组。动脉血氧分压H组明显高于N组 ;H组与N组BALF细胞数、BALF中蛋白含量、肺组织湿重 /干重比差异均有显著性 (P <0 0 5 ) ;肺组织中髓过氧化物酶的含量H组明显低于N组 (P <0 0 5 ) ;H组病理组织学改变较N组明显减轻 (P <0 0 5 ) ;PaCO2 与pH密切相关 ,与PaO2 、动态顺应性均呈正相关 ,与气道峰压呈负相关。结论 机械通气时吸入8%的CO2 所致高碳酸血症对ALI动物模型有保护作用 ,其机制可能与改善了肺力学、减少肺泡中蛋白质渗出 ,减轻多形核白细胞在肺内的扣押及抑制其活性有关。
Abstract Objective To obsearve pathologic and physiological indexes in ALI rabbits when vetilated with high concentration of carbon dioxide . Methods Twenty-two healthy New Zealand white rabbits were involved in this study. After confirmation of baseline stability ,six were randomly allocated to control group(Group C), the other sixteen were injected with oleic acid (0.1ml/kg) intravenously were randomized to noncapnic group(Group N,n=8) versus hypercapnic group(Group H,n=8). Some pathologic and physiological indexed were analyzed after three hours' mechanical ventilation. Results (1) Peak airway pressure in Group H was significantly lower than that in Group N and the dynamic lung compliance was significantly higher than that in Group N (P<0.05).PaO 2 in Group H was significantly higher than that in Group N (P<O. 05). (2) BALF cell counts, BALF protein content and lung tissue wet/dry ratio in Group H were significantly lower than that in Group N (P<0.05) . (3) Lung tissue myeloperoxidase in Group H was significantly lower than that in Group N (P<0.05). (4) Histologic damage in Group N was significantly severer than that in Group H (P<O. 05). (5)PaCO 2 was correlated with pH, PaO 2, dynamic lung compliance,peak airway pressure (r=-0.928, P<0.001; r=0.511, 0.526, -0.506, P<0.05,).Conclusion Hypercapnia induced by inspiring high concentration of carbon dioxide (8%)has protective effects on ALI rabbits. The mechanisms of protection might be associated with preservation of lung mechanics, reduction in alveolar protein and attenuation of PMN sequestration.
出处
《中华急诊医学杂志》
CAS
CSCD
2004年第6期386-388,共3页
Chinese Journal of Emergency Medicine
基金
辽宁省教育厅高等学校科学研究项目 ( 2 0 2 0 13 15 2 )
