麻醉对建立大鼠重度创伤失血性休克模型的保护性作用

Protective effect of anesthesia on the development of severe traumatic hemorrhagic shock in a rat model

目的建立一种改良重度创伤失血性休克(severe traumatic hemorrhage shock,STHS)大鼠模型,探讨麻醉对建立STHS大鼠模型的保护性作用。方法选择成年健康雄性SD大鼠40只,随机分成四组:正常组采用麻醉下行双侧股动脉、左股静脉置管后,等待大鼠清醒或维持麻醉分为清醒对照组(CC,n=10)、麻醉对照组(AC,n=10)、创伤休克组采用腹部开放性创口结合麻醉或清醒状态下定时定量控制性失血50%制作重度创伤失血性休克大鼠模型,分别为清醒创伤失血性休克组(CTHS,n=10)、麻醉创伤失血性休克组(ATHS,n=10)。观察各组大鼠在实验过程中的一般生理情况,持续监测实验大鼠血流动力学指标:平均动脉压(MAP)、心率(HR)、左心室压力最大上升/下降速率(±dp/dt max),动脉血气指标:pH值、氧分压(PaO2)、二氧化碳分压(PaCO2)、血红蛋浓度(ctHb)、乳酸(Lac)、血糖(Glu)、碳酸氢根浓度(cHCO3^-)、碱剩余(BE);到达实验终点时,采用HE染色镜下观察大鼠心脏、肝、肺、肾各脏器的损伤情况。结果CTHS、ATHS组HR、±dp/dt max随时间的变化均存在显著差异(P<0.01),ATHS组HR、±dp/dt max均呈降低趋势,而CTHS组先降低(T1)再升高或稳定(T2、T3、T4、T5、T6)状态;ATHS组休克后MAP呈逐渐上升趋势,最终恢复至正常水平25%~40%,而CTHS组经过代偿增长期后迅速下降。CTHS、ATHS组PH、PaCO2、ctHb、cHCO3^-、BE呈逐渐下降趋势,除PH、ctHb外,CTHS组下降幅度显著大于ATHS组(P<0.01);Glu、Lac、PaO2呈逐渐上升趋势,且CTHS组上升幅度显著高于ATHS组(P<0.01)。较CTHS组,ATHS组肝、心脏、肺、肾损伤程度显著降低。结论麻醉对建立大鼠重度创伤失血性休克发挥保护性作用,可以改善血流动力学,减少呼吸和代谢物累积,降低各器官损伤程度。

Objective To establish a modified rat model of severe traumatic hemorrhagic shock(STHS)and explore the protective effect of anesthesia on the development of STHS in a rat model.Methods Forty adult healthy male SD rats were randomly divided into four groups.The normal group was anesthetized with catheterization of the bilateral femoral artery and left femoral vein,and the rats waiting for consciousness or maintenance of anesthesia were divided into the conscious control group(CC,n=10)and the anesthetic control group(AC,n=10).The rats that suffer from severe traumatic hemorrhagic shock experience an open wound of the abdominal white line 5 cm with 50%bloodletting,and than,they were separated into two groups:the conscious traumatic hemorrhagic shock group(CTHS)and the anesthetic trauma hemorrhagic shock group(ATHS,n=10).The general physiological conditions of rats in each group were observed,and the following hemodynamic indexes of experimental rats were continuously monitored:mean arterial pressure(MAP),heart rate(HR),and maximum rise/fall rate of left ventricular pressure(±dp/dtmax).Arterial blood gas indexes,including pH value,the partial pressure of oxygen(PaO2),the partial pressure of carbon dioxide(PaCO2),hemoglobin concentration(ctHb),lactic acid(Lac),blood glucose(Glu),bicarbonate concentration(cHCO3^-),and base excess(BE),were also measured.At the end of the experiment,HE staining was performed to observe heart,liver,lung,and kidney injury in the rats.Results There were significant differences in the changes in HR and±dp/dtmax with time in CTHS and ATHS groups(P<0.01),whereas HR and±dp/dtmax decreased at first(T1)and then increased or stabilized(T2,T3,T4,T5,T6)in the CTHS group.After shock,the MAP in the ATHS group showed a gradual upward trend and finally returned to the normal level of 25%-40%,while that in the CTHS group decreased rapidly after the compensatory growth period.In CTHS and ATHS groups,PH,PaCO2,ctHb,cHCO3^-,and BE gradually decreased,and except for PH and ctHb,the decreases in the CTHS group were significantly higher than those in the ATHS group(P<0.01).Glu,Lac,and PaO2 showed a gradual upward trend,and the amplitude of the increase in the CTHS group was significantly higher than that in the ATHS group(P<0.01).The degree of liver,heart,lung,and kidney injury in the ATHS group was significantly lower than that in the CTHS group.Conclusions Anesthesia exhibits a protective effect on the development of severe traumatic hemorrhagic shock in rats,which can improve hemodynamics,reduce the accumulation of respiration and metabolites,and limit the degree of organ injury.