Vigileo原理和准确性

Vigileo’s心输出量监测技术的原理?“…主动脉脉搏压和每搏量SV是成比例的,并且和主动脉的顺应性负相关。”Boulain(CHEST2002;121:1245-1252)测定心率•通过波形的上升来识别心跳•从心跳的时间周期计算出心率校准血管的差异性(顺应性和阻力)•从人口统计学资料中评估不同病人的差异性•通过血压数据和波形分析评估动态的改变基于生理学原理,脉搏压(PP)和每搏量(SV)成比例•应用统计分析计算PP特性•在每一次心跳的基础上进行计算APStdevCO=HR*Sd(AP)*χ脉搏压的计算及其与每搏量的定量关系TrendingStrokeVolume•每秒采样血压100次•每搏量的改变会使得脉搏压相应的改变•准确测量整个脉搏周期的压力，并计算其标准差•动脉压标准差Sd(AP)脉搏压(PP)每搏量(SV)•每搏量（SV）计算取20秒平均值PPSV收缩压SBP舒张压DBP标准差（SD）是测量血压变异度的方法20sec.20sec.↑SV↑变异度↑Std(BP)↓SV↓变异度↓Std(BP)20sec.因此，对一个不变的血管状况……将血管状况对血流的影响包括在计算公式中Langewouters原理:血管顺应性关系05010015020025030000.0050.010.0150.020.0250.030.0350.040.0450.05PressureCompliance05010015020025030000.0050.010.0150.020.0250.030.0350.040.0450.05PressureCompliance05010015020025030000.0050.010.0150.020.0250.030.0350.040.0450.05PressureCompliance05010015020025030000.0050.010.0150.020.0250.030.0350.040.0450.05PressureComplianceFemaleMaleAge20Age50Age80Elasticityofthevessel•年龄和性别与血管顺应性相关•高血管顺应性降低血压变异度Sd（AP）及PP2101max1PPPPALPCP,[mmHg]Cv,(P)[cm2.mmHg]P0P1P1CvmaxCvmax/2A,[cm2]P,[mmHg]P0P0+P1P1AmaxAmax/2FemaleMaleAmaxP0P14.1272-0.89*Age57-0.44*Age5.6276-0.89*Age57-0.44*AgeVigileo™计算公式•血管顺应性10maxarctan15.0PPPAPALangewoutersGJ,etal,Thestaticelasticpropertiesof45humanthoracicand20abdominalaortasinvitroandtheparametersofanewmodel.JBiomechanics.1984;17:425-435血管特性对动脉压的影响•运算法则寻找影响血管特性的动脉压的特征性变化(i.e.,σap,MAP,Skewness,Kurtosis)•这些改变包括在SV的计算中斜率:反映血管顺应性MAP反映外周阻力峰态区分血压采样点•Arterialpulsepressurewaveformmoments–均值–变异度–斜率(ameasureforlackofsymmetry)–峰态(ameasureofhowpeakedorflatasampledistributionisfromnormaldistribution10111NkavgpkPNP1022211NkavgppPkPN103311NkpavgpPkPN104411NkpavgpPkPN先进的计算方法•对绝大多数病人来说，从主动脉弓到外周动脉，收缩压递增，而血流量递减动脉压力流量通常状况下的压力波形及流量先进的计算方法Recordedimmediatelyaftercoronarybypass2hoursaftercoronarybypassWeightedSkewness=1.1WeightedSkewness=0.1WeightedKurtosis=0.024WeightedKurtosis=0.071DifferenthemodynamicconditionsinthesamepatientChangesinVascularTone先进的计算方法TAPAPLangMAPPCBSAHRf43,...,,,)(,,一旦各因素相关性确定，相关顺应性计算变量矩阵建立，建立在血压数据上的SV就算就可以实现.CO=PR*SVwhereSV=*σap先进的计算方法TAPAPLangMAPPCBSAHRf43,...,,,)(,,一旦各因素相关性确定，相关顺应性计算变量矩阵建立，建立在血压数据上的SV就算就可以实现TheDynamicsofFloTrac脉搏率每搏量血管特性改变自动校准血管特性的改变IdenticalCOvalueswithsignificantdifferentarterialpressuresMcGeeWT,etal,ValidationofaContinuousCardiacOutputMeasurementUsingArterialPressureWaveform,posterattheISICEM,Brussels,2005KeyCCOICOFloTrac脉搏率每搏量血管特性改变自动校准血管特性的改变KeyCCOICOFloTracMeasuringChangesinStrokeVolumeandToneHorswellJL,etal,ArterialPressure-BasedMethodofContinuousCardiacOutputMonitoringAccuratelyFollowsTrendsinCardiacOutputDuringandAfterSurgery,presentedatSCCM2006.PulseRateStrokeVolumeVascularToneConclusions:Thisnovelarterialpressurecardiacoutputalgorithmprovidescardiacoutputassessmentsthatagreesatisfactorilyforclinicalpurposeswithintermittentandcontinuousthermodilutiontechniquesinpostoperativecardiacsurgicalpatients.Furtherstudyisrequiredforotherpatientpopulationsandclinicalsituations.