利多卡因预处理对大鼠吸入性急性肺损伤的影响

目的:探讨利多卡因预处理对人胃液吸入诱导大鼠急性肺损伤(ALI)的影响。方法:将SD大鼠40只,体重230~300g,雌雄不拘,随机分为5组(n=8):对照组、实验对照组(ALI组)和低、中、高剂量利多卡因组(L1~3组)。5组大鼠均行气管切开和股动、静脉置管。采用经气管导管注入人胃液(pH=1.5,0.8ml/kg)的方法建立大鼠ALI模型。C组和ALI组经股静脉注射生理盐水6.25ml/kg,并以每小时6.25ml/kg的速度持续泵入,L1~3组分别经股静脉注射利多卡因3.13mg/kg、6.25mg/kg、12.50mg/kg,并分别以每小时3.13mg/kg,6.25mg/kg,12.50mg/kg的速度持续泵入,10min后ALI组、L1~3组制备ALI模型,C组经气管导管注入0.9%NS0.8ml/kg。6h后以过量麻醉处死动物。于误吸后1h(T1)、6h(T2)取股动脉血样测IL-8,处死前取股动脉血样测血清蛋白浓度及血气分析。处死大鼠后立即行左肺灌洗,测定肺泡灌洗液(BALF)中白细胞计数(WBC总数)、多形核中性粒细胞(PMN)/白细胞(WBC)百分比及蛋白浓度,计算肺通透指数LPI(BALF总蛋白/血清蛋白),取右肺中叶测湿干重比(W/D),取右肺下叶光镜观察病理学改变。结果:与C组相比,ALI组和L1~3组IL-8、肺W/D、LPI、WBC总数明显升高(P<0.05);与ALI组相比,L1~3组IL-8、肺W/D、LPI、WBC总数及PMN/WBC显著降低(P<0.05);L1~3组各指标组间无显著性差异(P>0.05)。5组PO2和PCO2无显著性差异(P>0.05)。光镜观察:利多卡因预先给药各组肺组织病理学变化较ALI组减轻。结论:利多卡因预处理可减轻人胃液吸入诱导的大鼠急性肺损伤,但所设3种剂量利多卡因对大鼠急性肺损伤的预防效果无显著性差异。

Effects of Lidocaine pretreatment on acute lung injury induced by human gastric juice aspiration in rats

Objective：To investigate the effects of lidocaine on acute lung injury（ALI） induced by human gastric juice aspiration in rats.Methods：Forty SD rats of both sexes weighing 230～300 g were randomly divided into 5 groups（n=8 each）：group Ⅰ control;group Ⅱ ALI,group Ⅲ,Ⅳ and Ⅴ received lidocaine intravenously 3.13mg/kg bolus＋3.13mg/kg·h infusion,6.25mg/kg bolus＋6.25mg/kg·h infusion,12.5mg/kg bolus＋12.5mg/kg·h infusion respectively 10 min before human gastric juice instillation,and saline was given intravenously in the other two groups.ALI was induced by intratracheal human gastric juice（pH=1.5,0.8 ml/kg） in four groups.The other group received saline 0.8 ml/kg intratracheally.The animals were killed by overdose of pentobarbital sodium 6 h after the induction of ALI.The lungs were immediately removed for determination of W/D weight ratio,lung permeability index（LPI） and microscopic examination.The number of WBC and PMN/WBC in BALF were count.Serum IL-8 concentration was detected and blood gas analysis was also done.Results：Serum concentration of IL-8,lung W/D weight ratio,LPI,and WBC count in BALF were significantly higher in group Ⅱ,Ⅲ,Ⅳ,Ⅴ than those in group Ⅰ（P0.05）.Serum concentrations ,lung W/D weight ratio,LPI,WBC counts and PMN/WBC in BALF were significantly lower in groupⅢ,Ⅳ,Ⅴ than those in group Ⅱ（P0.05）.No significant difference was found in the indices mentioned above among group Ⅲ,Ⅳ,Ⅴ（P0.05）.There was also no significant difference in PO2 and PCO2 among the five groups（P0.05）.The damage to lung tissue in lidocaine pretreatment groups ameliorated compared with group ALI.Conclusion：Pretreatment with lidocaine can attenuate ALI induced by human gastric juice aspiration.