二维斑点追踪技术评价麻醉诱导和正压通气对不同容量状态时双心室功能的影响

2D-speckle tracking echocardiography assessing the effects of general anesthesia induction and positive pressure ventilation on bi-ventricular function in patients with different volume status

目的基于二维斑点追踪技术评价全麻诱导和正压通气对不同容量状态患者双心室功能的影响。方法选择择期全麻胃肠手术患者60例,男38例,女22例,年龄50-70岁,ASAⅠ或Ⅱ级。入室监护后行容量负荷试验,20 min内静脉输注生理盐水250 ml。于容量负荷试验前、后分别测量左心室流出道(LVOT)直径(D)和主动脉瓣速度时间积分(VTI),记录容量负荷试验前、后每搏输出量(SV),并计算ΔSV。根据ΔSV将患者分为两组:容量反应性阳性组(R组,ΔSV≥15%,n=33)和容量反应性阴性组(N组,ΔSV<15%,n=27)。容量负荷试验结束后10 min麻醉诱导前,行第1次经胸超声心动图检查。随后行全麻诱导,气管插管后行肺保护性通气(V_(T)7 ml/kg,PEEP 5 cmH_(2)O,FiO_(2) 60%),待麻醉诱导后10 min血流动力学平稳,行第2次经胸超声心动图检查。记录诱导前和诱导后心肌功能参数,采用二维斑点追踪技术测量左心室整体纵向应变(左心室GLS)和右心室游离壁纵向应变(右心室FWLS),计算各指标诱导前后的相对变化值。结果与诱导前比较,诱导后两组VTI、左心室GLS、三尖瓣环收缩期位移(TAPSE)、右心室FWLS明显降低(P<0.05);三尖瓣口血流舒张早期峰值速度与三尖瓣环舒张早期峰值速度比值(右心室E/E′)、右心室心肌做功指数(右心室MPI)明显升高(P<0.05)。诱导前后两组左心室射血分数(LVEF)、二尖瓣口血流舒张早期峰值速度与二尖瓣环舒张早期峰值速度比值(左心室E/E′)差异无统计学意义。与N组比较,R组主动脉瓣速度时间积分变化值(ΔVTI)、左心室整体纵向应变变化值(左心室ΔGLS)、三尖瓣环收缩期位移变化值(ΔTAPSE)、右心室游离壁纵向应变变化值(右心室ΔFWLS)明显降低(P<0.05);左心室做功指数变化值(左心室ΔMPI)、三尖瓣口血流舒张早期峰值速度与三尖瓣环舒张早期峰值速度比值变化值(右心室ΔE/E′)、右心室心肌做功指数变化值(右心室ΔMPI)明显升高(P<0.05)。两组左心室射血分数变化值(ΔLVEF)、二尖瓣口血流舒张早期峰值速度与二尖瓣环舒张早期峰值速度比值变化值(左心室ΔE/E′)差异无统计学意义。结论麻醉诱导和正压通气会诱发全麻患者左心室收缩功能及右心室收缩和舒张功能降低,在低血容量患者中尤为显著。

Objective To assess the effects of general anaesthesia induction and positive pressure ventilation on bi-ventricular function in patients with different volume status based on 2D-speckle tracking imaging(2D-STI).Methods Sixty elderly patients scheduled for elective gastrointestinal surgery under general anesthesia,38 males and 22 females,aged 50-70 years,ASA physical statusⅠorⅡ,were included in this study.After monitoring vital signs,all patients underwent volume expansion test(normal saline 250 ml was intravenously infused for 20 minutes),left ventricular outflow tract(LVOT)diameter(D)and aortic valve velocity time integral(VTI)were measured before and after volume expansion test.The stroke volume(SV)were recorded before and after volume expansion,andΔSV were calculated.Patients were divided into 2 groups according toΔSV:response group(group R,ΔSV≥15%,n=33)and non-response group(group N,ΔSV<15%,n=27).The first transthoracic echocardiography(TTE)examination was performed 10 minutes after the completion of volume expansion test before anesthesia induction.Then general anesthesia was induced and lung-protective ventilation was performed after endotracheal intubation(V_(T) 7 ml/kg,PEEP 5 cmH_(2)O,FiO_(2) 60%).After hemodynamic stability(10 minutes after anesthesia induction),a second transthoracic TTE examination was performed.Adopting 2D-STI based on quantitative analysis of myocardial motion to measure left ventricular global longitudinal strain(LV GLS)and right ventricular free wall longitudinal strain(RV FWLS).Cardiac function parameters were recorded before and after anesthesia induction.The relative change values of each index before and after induction were calculated.Results Compared with those index before anesthesia induction,aortic velocity time integration(VTI),LV GLS,tricuspid annulus systolic displacement(TAPSE),and RV FWLS were significantly reduced and ratio of the early diastolic peak velocity of tricuspid valve orifice to the early diastolic peak velocity of tricuspid ring(RV E/E′),right ventricular myocardial work index(RV MPI)were significantly increased after anesthesia induction in both groups(P<0.05);while there were no statistically significant differences between the left ventricular ejection fraction(LVEF)and the ratio of the early diastolic peak velocity of tricuspid valve orifice to the early diastolic peak velocity of tricuspid ring(LV E/E′).Compared with group N,ΔVTI,ΔLV GLS,ΔTAPSE,andΔRV FWLS were significantly lower in group R(P<0.05).ΔLV MPI,ΔRV E/E′,andΔRV MPI were significantly increased(P<0.05);whileΔLVEF andΔLV E/E′had no statistic difference.Conclusion Anaesthesia induction and positive pressure ventilation will suppress left systolic function and right systolic and diastolic function in patients without myocardial disease,especially in patients with low blood volume.Therefore,it is recommended that fluid responsiveness and basic cardiac function should be evaluated before anaesthesia induction and positive pressure ventilation performed in patients to prevent irreversible damage to cardiac function.