机械通气波型分析UnderstandingVentilationWaveform张翔宇喀什地区第二人民医院喀什地区第二人民医院喀什地区第二人民医院喀什地区第二人民医院同济大学上海市第十人民医院同济大学上海市第十人民医院呼吸机波型的基本概念Flow-TimeCurveFlow-TimeCurve流速时间曲线流速时间曲线流速时间曲线流速时间曲线Pressure-TimeCurvePressure-TimeCurve压力时间曲线压力时间曲线压力时间曲线压力时间曲线Volume-TimeCurveVolume-TimeCurve容量时间曲线容量时间曲线容量时间曲线容量时间曲线Pressure-VolumeLoopPressure-VolumeLoop压力容量环压力容量环压力容量环压力容量环FlowVolumeLoopFlowVolumeLoop流速容量环流速容量环流速容量环流速容量环其它高级监测图形其它高级监测图形一、用于理解人机同步Pressure-time curve:Pressure-time curve:病人与呼吸机之间的同步包括四个时相病人与呼吸机之间的同步包括四个时相:病人吸气触发呼吸机的过程病人吸气触发呼吸机的过程呼吸机被触发之后的响应过程呼吸机被触发之后的响应过程从吸气到呼气的切换从吸气到呼气的切换 呼气的终止呼气的终止TobinMJ,JubranA,andLaghiF.PatientVentilatorInteraction.AmJRespirCritCareMedVol163.Pp1059-1063,2001Critical Care Critical Care 2006,2006,10:10:236236一个呼吸周期中的四个时相一个呼吸周期中的四个时相无效触发Ineffectivetriggering双触发DoubletriggeringRise Time and EsensRise Time and EsensOvershootsupraplateau地震中的连枷胸病人地震中的连枷胸病人同步很重要FlailChestinAsynchronyRRVtPeakFlowInsp.PausePSPEEPTriggerFiO2PressureFlowVolumeMVspont吸气流量太低自主呼吸的吸气流速大于呼吸机的流速自主呼吸的吸气流速大于呼吸机的流速, ,提示有人机对抗或提示有人机对抗或设置的流速不足设置的流速不足压力压力容量容量0 0压力上升时间压力上升时间(Risetime,slope,et al)(Risetime,slope,et al)PCVPCV或或或或PSV(ASB)PSV(ASB)压力上升时间压力上升时间压力上升时间压力上升时间, , 调节上升时间即是调节呼吸机吸气流速的增加或减少调节上升时间即是调节呼吸机吸气流速的增加或减少调节上升时间即是调节呼吸机吸气流速的增加或减少调节上升时间即是调节呼吸机吸气流速的增加或减少c压压压压力力力力流流流流速速速速评估吸气触发阈和吸气作功大小压力时间曲线PTP二、导管阻力与气道阻力气道压升高是注意气道阻力增加与肺顺应性下降的区别压力压力时间时间气管导管阻塞气道阻力增大判断内源性呼气末正压(Auto-PEEP/PEEPi)的存在流速流速时间时间timeflowinhalationexhalation0auto-PEEPnormalconstant flowramp flowpressurecontrolPEEPi,autoPEEP流速曲线，流速曲线，A A显示气道阻力正常，显示气道阻力正常，B B显示气道阻力显示气道阻力增大，可见呼气峰值流速减慢，流速迅速减慢、增大，可见呼气峰值流速减慢，流速迅速减慢、曲线呈弯曲形，呼气时间延长，呼气末流速不能曲线呈弯曲形，呼气时间延长，呼气末流速不能减低至减低至0 0，提示内源性，提示内源性PEEPPEEP的存在的存在 F-VloopF-Vloop：气道阻力增大气道阻力增大肺大疱气道阻力气道阻力气道阻力增大气道阻力增大P-V loopP-V loopARDSARDS肺气肿肺气肿肺气肿肺气肿肺过度膨胀肺过度膨胀AARC Tmes July1999:10www.aarc.orgC20/C计算Pressure 会在吸气末屏气时自动计会在吸气末屏气时自动计算算 精确指示可能存在的肺过精确指示可能存在的肺过度牵张度牵张 C C20 20 = = 吸气末吸气末20% 20% 部部分的动态顺应性分的动态顺应性 C = C = 同一次呼吸的总同一次呼吸的总顺应性顺应性 C C2020/C ratios 0.8 /C ratios 0.8 可以可以看作肺过度牵张看作肺过度牵张 *Fisher/Mammel/Bing，PediatricPulmonology5:10-14(1988)PV-LoopVolumeOver-distensionbeginsC20LungOver-distensionC三、常见的呼吸机问题SIMV+PSV，通气管路存在漏气F-V loop and leakingF-V loop and leaking漏气漏气波型振荡呼吸机管路积水压力流量四、肺保护通气的应用准静态压力容量环（流速：15L/min）Phase2Phase14phasesPhase4Phase3PressureStartPEEPEndNewPEEPAutomaticswitchoverpointsP/-VTool2Start/StopCursor2Cursor1ActualSettingsP-startcmH2OP-topcmH2OendPEEPcmH2ORampspeedcmH2O/sT-pausesT-totalsSettingsClose3.783015492XxxxxxxxxerttrertXxxxxxxxxerttrertXxxxxxxxxerttrertPV2000-/12-1215:33:34Plot535103231History1/5Cursor1Cursor2CcursorInsp.limb100/5900/2237.5Exp.limb155/51120/2236.5P/VToolCurrentsettingsTotaltimeOpenssettingwindowStart/StopbuttonCursorbuttonsOpensPlotwindowSelectsandviewsstoredcurvesDate&timeStoredcurvesExpiratorylimb(yellow)Inspiratorylimb(green)AssistlinesInspiratorylimbExpiratorylimbComplianceforforeachlimbCursor2oneachlimbCursor1oneachlimbProtocolResultBobsnewprotocolBobsnewprotocolAcomparisonofmethodstoidentifyopen-lungPEEP.CaramezMP,KacmarekRM,etalCaramezMP,KacmarekRM,etalInthisanimalmodelofARDS,dynamictidalrespiratorycompliance,maximumPaO2,maximumPaO2+PaCO2,minimumshunt,inflationlowerPflexandPmci,iyieldsimilarvaluesforPEEPfollowingarecruitmentmaneuver.IntensiveCareMed.2009Apr;35(4):740-7.肺复张趋势图（LPP）最佳顺应性最佳顺应性“PEEP递降测试法递降测试法J.J.HAITSMA,B.LACHMANNMINERVAANESTESIOL2006;72:117-32开放肺的步骤开放肺的步骤2007南京，Lecture&workshop牵张指数（Stressindex）CritCareMed2004Vol.32,No.4:1018压力时间曲线可以利用需要恒定低流速需要恒定低流速需要镇静、肌松需要镇静、肌松观察凹、凸、直线观察凹、凸、直线注意吸气开始与结注意吸气开始与结束时流速不稳定阶束时流速不稳定阶段不是评价段段不是评价段缺点是不易准确量缺点是不易准确量化化CONCLUSIONCONCLUSION：OurstudyOurstudydemonstratesdemonstratesthatinalunglavagemodelofALI,thatinalunglavagemodelofALI,theshapeofthePaw-tcurvetheshapeofthePaw-tcurveduringconstantflowinflationduringconstantflowinflationdetectsCTscanevidenceoftidaldetectsCTscanevidenceoftidalrecruitmentandtidalrecruitmentandtidalhyperinflation:Aprogressivehyperinflation:AprogressiveincreaseinslopeofthePaw-tincreaseinslopeofthePaw-tcurveindicatestidalrecruitment,curveindicatestidalrecruitment,andaprogressivereductioninandaprogressivereductioninslopeofthePaw-tcurveslopeofthePaw-tcurvecorrespondstotidalcorrespondstotidalhyperinflation.AstraightPaw-thyperinflation.AstraightPaw-tcurveindicatesthattidalinflationcurveindicatesthattidalinflationoccursonlyinthenormallyoccursonlyinthenormallyaeratedcompartment.aeratedcompartment.CritCareMed2004Vol.32,No.4:1018五、更多呼吸力学气管内直接测压 Intended Intended typically for typically for intermittent useintermittent use More accurately More accurately displays actual displays actual pressures pressures transmitted to the transmitted to the airwaysairways Provides ability Provides ability to measure to measure imposed Work imposed Work and Resistanceand ResistanceEvaluation of pressure/volume loops based on intratracheal pressure measurements during Evaluation of pressure/volume loops based on intratracheal pressure measurements during dynamic conditions;S.Karason et al, Acta Anesthesiol Scand 2000;44:571-577dynamic conditions;S.Karason et al, Acta Anesthesiol Scand 2000;44:571-577间接计算气管内压：PAV+同时计算阻力与做功（PAV+50%）EsophagealBalloonApproximatespleuralApproximatespleuralpressurepressurePolyethylenePolyethylene10cmlongballoon10cmlongballoon100cmlongtubing100cmlongtubingPositionedinthelower1/3Positionedinthelower1/3oftheesophagusoftheesophagusFilledwith0.5-1.0ccairFilledwith0.5-1.0ccairProperplacementoftheballoonisimperativeforaccuratemeasurements.Anapproximatelevelofplacementcanbemadebymeasuringthedistancefromthetipofthenosetothebottomoftheearlobeandthenfromtheearlobetothedistaltipofthexiphoidprocess.Baydur Baydur Method, to Method, to confirm confirm balloon balloon placementplacement红线红线红线红线显示根据显示根据显示根据显示根据AWAW计算的上拐点计算的上拐点计算的上拐点计算的上拐点 绿线显示绿线显示绿线显示绿线显示根据根据根据根据 TATA(TA=AW(TA=AWES)ES)所计算的高拐点所计算的高拐点所计算的高拐点所计算的高拐点如果根据红线设置如果根据红线设置如果根据红线设置如果根据红线设置吸气峰压，胸壁限吸气峰压，胸壁限吸气峰压，胸壁限吸气峰压，胸壁限制严重的病人会出制严重的病人会出制严重的病人会出制严重的病人会出现通气不足现通气不足现通气不足现通气不足TA = Transaveolar curveAW = Airway curveES = Esophageal (pleural) curve区分肺区分肺/胸壁对静态压力胸壁对静态压力-容量曲线的影响容量曲线的影响NEnglJMed2008;359:2095-104FlowFlowAirway PressureAirway PressureAutoPEEP(AirTrapping)AutoPEEP(AirTrapping)Static PEEPStatic PEEPii End-Expiratory HoldEnd-Expiratory HoldExp Exp HoldHoldExp Exp HoldHoldSet PEEP = 0 Set PEEP = 0 cmHcmH2 2OOStatic Static PEEPPEEPi iStatic Static PEEPPEEPi iFlowFlowAirway PressureAirway Pressure呼气末阻断法监测autoPEEP的问题在自主呼吸的病人无法监测如果病人存在小气道在呼气末塌陷，也无法监测(flowdependentairways)经常出现假阴性AutoPEEP1. Patient trigger 1. Patient trigger work before PEEP work before PEEP appliedapplied2. Note PEEP 2. Note PEEP applicationapplication3. Patient trigger 3. Patient trigger work after PEEP work after PEEP appliedapplied监测由于气流受限而引起的内源性监测由于气流受限而引起的内源性监测由于气流受限而引起的内源性监测由于气流受限而引起的内源性PEEPPEEP而增加的触发功而增加的触发功而增加的触发功而增加的触发功呼出气CO2监测AirtrapandPEEPiRe-breathingCO2体积检测重要的参数n n生理死腔量与生理死腔量与潮气量比值潮气量比值Phys VPhys VD D / V / VT Tn n肺泡通气量肺泡通气量n n每分钟每分钟COCO2 2呼呼出量出量( ( VCOVCO2 2 ) )XYZPaCO2-PeCO2PaCO2Y+ZX+Y+Z=使用NICO监测撤机状况