超声在猪心肺复苏后肺损伤评估中的应用价值

The value of lung ultrasound score to evaluate lung injury in a porcine model of cardiopulmonary resuscitation

目的探讨超声在猪心肺复苏后肺损伤动态评估中的应用价值。方法国产健康雄性猪10头,体质量(35.9±2.4)kg,随机数字法表分为假手术组、心肺复苏组各5头。假手术组仅常规麻醉和气管插管,心肺复苏组在常规麻醉和气管插管后经历心脏骤停与复苏,于复苏前和复苏后1、3、6、12h应用肺超声评分(LUS)评估肺损伤情况,同时进行血气分析监测氧合指数(PaO2/FiO2),脉搏指示连续派血量法测定血管外肺水指数(EVLWI)和肺毛细血管通透性指数(PVPI)。采用重复方差分析各指标的动态变化,分析LUS与PaO2/FiO2、EVLWI、PVPI的相关性。结果两组动物的基本参数具有可比性。假手术组各指标的动态变化差异无统计学意义。心肺复苏组的PaO2/FiO2变化差异无统计学意义,但在复苏后1、3和6h均低于相应时点的假手术组。EVLWI和PVPI在复苏后持续升高(F=17.96、27.70,P<0.001),EVLWI从基线的(9.7±1.3)mL/kg升高到12h的(21.0±5.5)mL/kg,PVPI从(2.3±0.7)mL/kg升到(6.1±0.5)mL/kg,且均高于假手术组同时点的相应值。复苏组的LUS也持续升高(F=34.2,P<0.001),基线和复苏后1、3、6、12h分别为(2.6±0.5)、(13.4±0.9)、(15.0±1.9)、(15.8±0.8)和(17.6±4.0)分,均高于假手术组同时点的值。相关性分析显示,LUS与PaO2/FiO2呈负相关(r=-0.625,P<0.001),与EVLWI、PVPI正相关(r=0.790、0.882,P<0.001)。结论在猪心肺复苏模型中,肺超声评分与传统肺损伤指标的相关性较好,可以实时、连续无创地评估复苏后肺损伤的程度,值得进一步的临床应用研究。

Objective To investigate the value of lung ultrasound score in evaluating lung injury in a porcine model of cardiopulmonary resuscitation.Methods Ten male domestic swine were randomly assigned to sham control and cardiopulmonary resuscitation (CPR) groups.The sham operation group only underwent routine anesthesia and tracheal intubation,and the cardiopulmonary resuscitation group experienced cardiac arrest and resuscitation after routine anesthesia and endotracheal intubation.Lung ultrasound score (LUS),PO2/FiO2,extravascular lung water index (EVLWI),and pulmonary vascular permeability index (PVPI) were measured at baseline and at 1h,3h,6h,and 12h after resuscitation.The repeated variance analysis was used to analyze the dynamic changes of each index,and the correlation between LUS and PaO2/FiO2,EVLWI and PVPI was analyzed.Results (1) The basic parameters of the two groups were comparable.(2) There was no statistical difference in the change of the indexes in the sham group.Although PO2/FiO2 had no change in the CPR group,the value of PO2/FiO2 was lower than that of the control group at 1h,3h,6h after ROSC [(346.7±52.1)mmHg vs.(449.5±38.5)mmHg,(367.6±49.2)mmHg vs.(443.8±47.9)mmHg,(336.2±38.9)mmHg vs.(429.5±39.8)mmHg,P <0.05].After resuscitation,EVLWI and PVPI in CPR group were increased from (9.7±1.3)mL/kg to (21.0±5.5)mL/kg( F=17.96,P <0.001) and from 2.3±0.7 to 6.1±0.5( F=27.70,P <0.001).All values were higher than those of the sham group.The lung ultrasound score increased [(13.4±0.9) vs.(3.6±1.3) at 1h,(15.0±1.9) vs.(3.6±1.3) at 3h,(15.8±0.8) vs.(3.2±1.6) at 6h and (17.6±4.0) vs.(3.8±0.8) at 12h,P <0.05],and all values were higher than those of the sham group.(3) The increase in LUS was highly correlated with increase in ELWI( r=0.790;P <0.001) and PVPI( r=0.882;P <0.001),and decreases in PO2/FiO2( r=-0.625;P <0.001).Conclusion In the porcine model of cardiac resuscitation,the correlation between lung ultrasound score and traditional lung injury indexes are good.Thus,lung ultrasound is a feasible approach to evaluate lung injury dynamically.The clinical application is worthy of further researches.