机械通气的模式.ppt
PRVC“双重模式”算法简述CL或病人需求减少CL 或病人需求增加恢复VT(500 ml)VT(600 ml)PTARGETPTARGETPTARGETVT (500 ml)restoredResulting Vt(500 ml)FlowPressureInspExhVT (400 ml)双重模式中的目标通气目标容量(500 ml)VT容量支持VS与PRVC相似的有PPEAKcmH2OINSPL/minEXPV.NBP840:VV+=VC+VS实际实际 Vt 设定设定 Vt 目标目标 VT 恢复恢复 VT (500 ml)PTargetP TargetTarget volume(500 ml)VT (400 ml)顺应性降低顺应性降低两种不同的呼吸方式保证预置的目标潮气量，同时允许病人自主呼吸 双重目标模式的目标新模式的目的Ventilator Induced Lung Injury临床研究结果通气/血流比ventilation/perfusiondorsalL/minMandatoryventilationdorsalL/minSpontaneous breathing保持病人-呼吸机同步Current Opinion in Critical Care 2002,8:5157Current Opinion in Critical Care 2005,11:6368Christian PutensenAugust,2006August,2006August,2006Synchrony:patient and ventilator呼吸功WOB双重目标模式的应用双重目标模式的评价压力目标+自主呼吸支持Bi-LevelPressureTimePhighPlowPressure SupportAPRVPressureTimePhighPlowPutensen AJRCCM 2001;164:43 APRVPutensen AJRCCM 2001;164:43APRV其它新的功能TC,气道阻力与流速的关系7.5mm导管两端压力差导管两端压力差PS的局限性10PCIRCcmH2OINSPLminEXP7.5 5 2.5 0-5-108060 40 20020-804060V.04812s2610Higher FlowInsufficient SupportTC/ATCATCNBP840f1m in1605V-TRIG.3.75TH S1.751.751:1.142.0P%50H2OP E E PH20cmO2%50TCc m%SUPP90%VSEN SLm in5BiLEVELPCP E E PL5.0c mH2OTube I.D.5.5 m mTube TypeETMatch to patientPCIRCH2O25VTI SPONT500 m lESENS10%P E E PL5.0H2ODrger Evita 4TC的优点TC/ATC并不能:Haberthur ICM 1999;25:514Does the tube-compensation function of two modern mechanicalventilators provide effective work of breathing relief?Animal Lab on SynchronyAsia Vent Forum Shanghai TCI VentilatorFlowPatientEffort Artifact TriggerOccurrence of leak Missed Trigger Delayed Trigger漏气补偿 Leak compensation,ALCAutomatic Leak Compensation Effective Automatic Leak Compensation Occurrence of leakVentilatorFlowPatientEffort Patient Triggers Only Patient Trigger Patient Trigger Patient Trigger Patient Trigger Patient Trigger Patient Trigger Patient Trigger Patient Trigger漏气补偿 Leak compensation,ALC压力上升时间与吸气终止12345630SecPawcmH2O-10Flow too lowRisetime/Pressure slope,EsensOvershootsupraplateauInspirationtermination Criteria(Esens)25%of peak flow in most cases以往呼吸机的固定Esens现代呼吸机的可调EsensEsens设置过高,Flowsensor failRespir Care 2001 Jul;46(7):666-77Evaluation of inspiratory rise time and inspiration termination criteria in new-generation mechanical ventilators:a lung model study.Chatmongkolchart S,Williams P,Hess DR,Kacmarek RM.“We would expect the next generation of mechanical ventilators to be able to assess patient synchrony during pressure ventilation and to automatically adjust rise time and inspiration termination criteria on a breath-by-breath basis.”自动压力上升时间与吸气终止e500Automatic system on a COPD Patient20 0 1 0-1 4-6Peso Flow Paw1 secVentilator with a fixed 5%Flow Cycle Threshold on a COPD Patient20 0 1 0-1 4-6Peso Paw Flow1 sec (A)High Inspiratory Effort(60 L/min)Du HL,Amato MBP,Yamada Y.Respiratory Care Clinics North America 2001;7(3)e500SV300 1.0 0.8 0.6 0.4 0.2 0-0.2Termination Delay Time(s)R5 R5 R5 R20 R20 R20 C80 C40 C20 C80 C40 C20Automatic Pressure Support Cycling-off Threshold Adjustment (B)Low Inspiratory Effort(30 L/min)Du HL,Amato MBP,Yamada Y.Respiratory Care Clinics North America 2001;7(3)e500SV300Termination Delay Time(s)1.0 0.8 0.6 0.4 0.2 0-0.2 R5 R5 R5 R20 R20 R20 C80 C40 C20 C80 C40 C20Automatic Pressure Support Cycling-off Threshold AdjustmentPAV与PPSPAVPAV-压力曲线的综合PPP辅助比例要小于100%理论上辅助比例达理论上辅助比例达100%100%时时,患者呼吸肌作功可减小患者呼吸肌作功可减小至至0.0.但由于呼吸机本身技术和患者隐定性的限制但由于呼吸机本身技术和患者隐定性的限制和由于和由于PAVPAV本身作用机理这两个因素易发生脱逸现本身作用机理这两个因素易发生脱逸现象象(即过度补偿即过度补偿):):VAVA过度补偿可出现过度补偿可出现:(a):(a)呼吸机持续送气出现高呼吸机持续送气出现高容量报警或可见及患者主动使用呼气肌呼气容量报警或可见及患者主动使用呼气肌呼气,(b),(b)流速曲线快速上升到一个高水平后突然下降中断流速曲线快速上升到一个高水平后突然下降中断.FAFA过度补偿过度补偿使呼吸机明显处于使呼吸机明显处于 误触发误触发 且不能用且不能用设定流量触发来纠正设定流量触发来纠正.发生脱逸现象导致呼吸机发生脱逸现象导致呼吸机持续送气持续送气,产生肺过度膨胀或气压伤产生肺过度膨胀或气压伤.因此因此PAVPAV辅辅助比例以低于助比例以低于80%80%以下最为安全以下最为安全.设置VA,FA有三法:预置预置VA=80%VA=80%Ers Ers 或计算的或计算的ErsErs2cmH2cmH2 2O O预置预置FA=80%FA=80%Rrs Rrs 或计算的或计算的Rrs-2cmHRrs-2cmH2 2O O根据根据P-VP-V环设置环设置PEEPPEEP 脱逸法脱逸法 根据患者自觉舒适程度来调节根据患者自觉舒适程度来调节PPSPPSPPSPPS的优点和局限性PS与PPS的差别PAV+is a simple modeIt provides the best way to improve patient-ventilator synchronyPotential advantages of PAV+PAV+90%Patient brainPhysician brainInformationResponsePAV+is a simple modeThe physician just sets the%of support,FIO2 and PEEP and the ventilator is responsible for the synchrony Alveolar VentilationOxy.TpRatePinspTiTePFFiO2PEEPVtCMVSIMVPCVPSVConventionalFiO2PEEPMVAutomaticAutomatic ventilationPinsp RRIMVPinsp RRIMVPinsp RRIMV Pinsp RRIMV(Pmax-PEEP)*Cdyn5 b/min20/RCexp2*VdAdaptive Support VentilationControls in ASVSultzer,Anesthesiology,2001Petter,Anesth Analgesia,2003 How good is ASV?Tasseaux,CCM 2000How good is ASV?ASV:which patient?Prospective study:7 months period 1349 days of invasive ventilation Arnal JM.Intensive Care Med 2004;30:S84(abstract)NAVAEstimated Ppeak(Pest)in NAVA=NAVA Level x(Edi peak Edi min)+PEEPVTfspontetCO2呼吸稳定呼吸稳定:PS PS 撤机撤机:PS Closed loop ventilationPatientVentilator 基本原理f_spnVTetCO2通气分类通气分类PS值调节值调节 呼吸舒适区呼吸舒适区f_spnVTetCO2
