COPD患者的機(jī)械通氣北京協(xié)和醫(yī)院杜斌利益沖突(ConflictsofInterest)TycoDraegerMaquetHamiltonTaemaViasysMechanicalVentilationofCOPD/Asthma|BinDuAECOPD的病理生理MechanicalVentilationofCOPD/Asthma|BinDuAirwayinflammationAirwaynarrowing&obstruction

FrictionalWOBShortenedmuscles,

curvatureAirtrappingAuto-PEEP

VE

musclestrength

Vt

VA

PaCO2

pH

PaO2

ElasticWOB

VCO2SteroidsAbxBDsMV?IPAPMV?IPAPMVPEEPAECOPD的病理生理機(jī)制呼氣氣流的驅(qū)動(dòng)壓降低肺彈性回縮力不明原因的異常下降呼氣相吸氣肌肉活動(dòng)導(dǎo)致胸壁向外的回縮力異常升高氣道阻力顯著升高氣道半徑縮小呼氣相聲門(mén)裂狹窄后果肺過(guò)度充盈（FRC增加到正常值的2倍）呼吸系統(tǒng)時(shí)間常數(shù)增加MechanicalVentilationofCOPD/Asthma|BinDuPeressL,SybrechtG,MacklemPT.Themechanismofincreaseintotallungcapacityduringacuteasthma.AmJMed1976;61:165-169McCarthyDS,SigurdsonM.Lungelasticrecoilandreducedairflowinclinicallystableasthma.Thorax1980;35:298-302ColebatchHJ,FinucaneKE,SmithMM.Pulmonaryconductanceandelasticrecoilrelationshipsinasthmaandemphysema.JApplPhysiol1973;34:143-153CormierY,LecoursR,LegrisC.Mechanismsofhyperinflationinasthma.EurRespirJ1990;3:619-624CollettPW,BrancatisanoT,EngelLA.Changesintheglotticapertureduringbronchialasthma.AmRevRespirDis1983;128:719-723PepePE,MariniJJ.Occultpositiveend-expiratorypressureinmechanicallyventilatedpatientswithairflowobstruction:theauto-PEEPeffect.AmRevRespirDis1982;126:166-170RanieriVM,GrassoS,FioreT,GiulianiR.Auto-positiveend-expiratorypressureanddynamichyperinflation.ClinChestMed1996;17:379-394時(shí)間常數(shù)(τ)Tau呼氣容積殘余容積00%100%163.0%37.0%395.0%5.0%599.9%0.1%健康成人2x0.10=0.20”術(shù)后氣管插管成人5x0.06=0.30”COPD成人15x0.06=0.90”ARDS成人8x0.03=0.24”ARDS患兒5x0.01=0.05”MechanicalVentilationofCOPD/Asthma|BinDu動(dòng)態(tài)過(guò)度充盈的發(fā)病機(jī)制MechanicalVentilationofCOPD/Asthma|BinDuinspexpTimeVTVEETidalvolumeTrappedgasLungVolumeFRCObstructedLungsNormalStiffLungsLevyBD,KitchB,FantaCH.Medicalandventilatorymanagementofstatusasthmaticus.IntensiveCareMed1998,24:105-117.VEI=VT+VEE動(dòng)態(tài)過(guò)度充盈的發(fā)病機(jī)制MechanicalVentilationofCOPD/Asthma|BinDuHubmayrRD,AbelMD,RehderK.Physiologicapproachtomechanicalventilation.CritCareMed1990;18:103-113動(dòng)態(tài)過(guò)度充盈的監(jiān)測(cè)吸氣末肺容積(VEI)60”窒息過(guò)程中從吸氣末至靜態(tài)FRC的呼氣容積需要完全肌松與其他指標(biāo)相比預(yù)測(cè)氣壓傷并無(wú)優(yōu)勢(shì)autoPEEP低估實(shí)際autoPEEPPplat足夠長(zhǎng)的吸氣暫停時(shí)間沒(méi)有漏氣MechanicalVentilationofCOPD/Asthma|BinDuOddoM,FeihlF,SchallerM,etal.Managementofmechanicalventilationinacutesevereasthma:practicalaspects.IntensiveCareMed2006;32:501-510Pplat的監(jiān)測(cè)：吸氣暫停時(shí)間MechanicalVentilationofCOPD/Asthma|BinDuBarberisL,MannoE,GuerinC.Effectofend-inspiratorypausedurationonplateaupressureinmechanicallyventilatedpatients.IntensivecareMed2003;29:130-134Pplat的監(jiān)測(cè)：吸氣暫停時(shí)間MechanicalVentilationofCOPD/Asthma|BinDuBarberisL,MannoE,GuerinC.Effectofend-inspiratorypausedurationonplateaupressureinmechanicallyventilatedpatients.IntensivecareMed2003;29:130-134autoPEEP與動(dòng)態(tài)過(guò)度充盈MechanicalVentilationofCOPD/Asthma|BinDuOddoM,FeihlF,SchallerM,etal.Managementofmechanicalventilationinacutesevereasthma:practicalaspects.IntensiveCareMed2006;32:501-510肺泡通氣：二室模型MechanicalVentilationofCOPD/Asthma|BinDuP2P1RcPiR1R2C1C2Rc=4R1=1.0R2=0.5C1=0.20C2=0.40P1(t)–P2(t)=kVk≈C1R1–C2R2C1+C2.VPiP1P2V1/V2k0.33.82.52.50.501.06.82.52.50.500Rc=4R1=0.5R2=5.0C1=0.01C2=0.40VPiP1P2V1/V2k0.36.35.13.60.041.012.48.43.50.06-5HubmayrRD,AbelMD,RehderK.Physiologicapproachtomechanicalventilation.CritCareMed1990;18:103-113COPD機(jī)械通氣適應(yīng)證呼吸肌疲勞且瀕臨呼吸停止盡管進(jìn)行充分的保守治療,PaCO2仍進(jìn)行性升高勞累和(或)高碳酸血癥導(dǎo)致意識(shí)狀態(tài)惡化高濃度吸氧治療無(wú)效的低氧血癥痰液清除障礙導(dǎo)致病情惡化呼吸驟停MechanicalVentilationofCOPD/Asthma|BinDuCOPD機(jī)械通氣的目的緩解呼吸肌疲勞改善氣體交換，使其恢復(fù)至基礎(chǔ)水平防止動(dòng)態(tài)過(guò)度充盈和（或）auto-PEEP加重，以免導(dǎo)致循環(huán)功能衰竭M(jìn)echanicalVentilationofCOPD/Asthma|BinDuCOPD機(jī)械通氣策略控制性低通氣(controlledhypoventilation)最先由Darioli和Perret于1984年提出不同于允許性高碳酸血癥(permissivehypercapnia)嚴(yán)重氣流梗阻患者難以糾正PaCO2增加分鐘通氣量可加重過(guò)度充盈及死腔糾正高碳酸血癥效果有限MechanicalVentilationofCOPD/Asthma|BinDuLeathermanJW.Mechanicalventilationforsevereasthma.RespirCare2007;52:1460-1461確定COPD基礎(chǔ)氣體交換水平ABG考慮思路是否需要處理？平時(shí)PaCO2如何？既往結(jié)果的提示如果沒(méi)有既往結(jié)果…MechanicalVentilationofCOPD/Asthma|BinDupH 7.202PaCO2 89.2mmHgPaO2 58.9mmHgSaO2 91.9%HCO3 37.9mmol/LBE 11.9mmol/LLA 2.2mmol/L確定COPD基礎(chǔ)氣體交換水平ABG考慮思路如何根據(jù)急性發(fā)作時(shí)ABG確定平時(shí)的PaCO2？pH≈PaCO2/HCO3pH≈40/24≈PaCO2/37.9MechanicalVentilationofCOPD/Asthma|BinDupH 7.202PaCO2 89.2mmHgPaO2 58.9mmHgSaO2 91.9%HCO3 37.9mmol/LBE 11.9mmol/LLA 2.2mmol/L確定COPD氣體交換目標(biāo)以PaCO2不低于基礎(chǔ)水平為目標(biāo)e.g.PaCO268mmHg,pH7.18@MinVent9lpm允許范圍PaCO2<90mmHgpH>7.20MechanicalVentilationofCOPD/Asthma|BinDuLeathermanJW,McArthurC,ShapiroRS.Effectofprolongationofexpiratorytimeondynamichyperinflationinmechanicallyventilatedpatientswithsevereasthma.CritCareMed2004;32:1542-1545PaCO2的影響因素

VCO2

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WOB

代謝發(fā)熱CHO

T4

VA

VE

RR

Vt

Vd(不伴

VE)MechanicalVentilationofCOPD/Asthma|BinDuPaCO2≈VCO2MinVent(1–Vd/Vt)死腔增加時(shí)不應(yīng)盲目增加分鐘通氣量MechanicalVentilationofCOPD/Asthma|BinDu

Vt

Palv

生理死腔MinVent

PEEP

ITPPaO2

PvO2

CO

休克COPD機(jī)械通氣：減輕動(dòng)態(tài)過(guò)度充盈降低潮氣量減慢呼吸頻率降低呼氣阻力縮短吸氣時(shí)間增加吸氣流量使用硬質(zhì)管路降低CO2產(chǎn)量MechanicalVentilationofCOPD/Asthma|BinDuStatherDR,StewartTE.Mechanicalventilationinsevereasthma.CritCare2005;9:581-587降低分鐘通氣量是避免氣體閉陷最有效的方法AECOPD/哮喘機(jī)械通氣初始設(shè)置呼吸參數(shù)設(shè)置模式VCV分鐘通氣量<10lpm潮氣量6–10ml/kgPBW呼吸頻率10–14bpm平臺(tái)壓<30cmH2O吸氣流量60–80lpm吸氣流量波形減速氣流呼氣時(shí)間4–5sPEEP0cmH2OFIO2SaO2>90%MechanicalVentilationofCOPD/Asthma|BinDuOddoM,FeihlF,SchallerM,etal.Managementofmechanicalventilationinacutesevereasthma:practicalaspects.IntensiveCareMed2006;32:501-510COPD機(jī)械通氣模式的選擇MechanicalVentilationofCOPD/Asthma|BinDuOddoM,FeihlF,SchallerM,etal.Managementofmechanicalventilationinacutesevereasthma:practicalaspects.IntensiveCareMed2006;32:501-510控制vs.輔助深度鎮(zhèn)靜+/-肌松以避免人機(jī)不同步定容vs.定壓氣道阻力和autoPEEP很高時(shí)，壓力控制可能導(dǎo)致肺泡低通氣氣道梗阻迅速緩解時(shí)，壓力控制可能導(dǎo)致呼吸性堿中毒定容通氣沒(méi)有上述風(fēng)險(xiǎn)，但需密切監(jiān)測(cè)氣道壓力MinVent恒定時(shí)的潮氣量MechanicalVentilationofCOPD/Asthma|BinDuTuxenDV,LaneS.Theeffectsofventilatorypatternonhyperinflation,airwaypressures,andcirculationinmechanicalventilationofpatientswithsevereair-flowobstruction.AmRevRespirDis1987;136:872-879COPD吸氣氣流波形MechanicalVentilationofCOPD/Asthma|BinDuYangSC,YangSP.Effectsofinspiratoryflowwaveformsonlungmechanics,gasexchange,andrespiratorymetabolisminCOPDpatientsduringmechanicalventilation.Chest2002;122:2096-2104COPD吸氣氣流波形吸氣氣流波形呼吸機(jī)參數(shù)恒定氣流1正弦波減速氣流恒定氣流2Vt,ml562±67558±65566±59571±72RR,bpm18.2±1.718.6±1.418.4±1.918.5±1.3MV,lpm10.4±1.610.3±1.510.6±1.610.7±1.8Ti/Ttot0.29±0.040.28±0.030.29±0.040.28±0.03平均吸氣流量,lpm38±537±739±738±6MechanicalVentilationofCOPD/Asthma|BinDuYangSC,YangSP.Effectsofinspiratoryflowwaveformsonlungmechanics,gasexchange,andrespiratorymetabolisminCOPDpatientsduringmechanicalventilation.Chest2002;122:2096-2104COPD吸氣氣流波形吸氣氣流波形呼吸力學(xué)參數(shù)恒定氣流1正弦波減速氣流恒定氣流2PIP,cmH2O47.1±11.547.8±10.839.5±9.746.6±11.0Paw,cmH2O7.6±4.27.2±4.88.4±4.58.4±3.9Pplat,cmH2O20.2±9.119.6±10.618.9±8.821.4±10.4Vd/Vt,%58.4±5.254.5±6.348.6±5.557.6±4.9Cst,ml/cmH2O35.3±8.935.8±11.236.6±9.337.2±9.7MechanicalVentilationofCOPD/Asthma|BinDuYangSC,YangSP.Effectsofinspiratoryflowwaveformsonlungmechanics,gasexchange,andrespiratorymetabolisminCOPDpatientsduringmechanicalventilation.Chest2002;122:2096-2104COPD吸氣氣流波形吸氣氣流波形恒定氣流1正弦波減速氣流恒定氣流2pH7.44±0.047.44±0.077.43±0.067.44±0.04PaO2/FiO2,mmHg236±73231±65223±70227±67PaCO2,mmHg45±1045±1037±946±12A-aDO2,mmHg133.1±36.5136.4±34.2156.3±33.7134.4±35.3HR,bpm106.1±18.1108.3±20.2105.3±18.9109.9±20.5MAP,mmHg92±2388±1888±2190±19MechanicalVentilationofCOPD/Asthma|BinDuYangSC,YangSP.Effectsofinspiratoryflowwaveformsonlungmechanics,gasexchange,andrespiratorymetabolisminCOPDpatientsduringmechanicalventilation.Chest2002;122:2096-2104COPD吸氣氣流波形吸氣氣流波形參數(shù)恒定氣流1正弦波減速氣流恒定氣流2WOB,J/L0.92±0.160.88±0.180.75±0.150.92±0.18Raw,cmH2O/L/s12.6±3.112.4±3.611.2±2.412.5±3.3VO2,ml/min384±53389±60377±49382±52VCO2,ml/min274±52280±47273±56276±55癥狀評(píng)分54.5±13.458.6±11.942.7±12.356.1±12.8MechanicalVentilationofCOPD/Asthma|BinDuYangSC,YangSP.Effectsofinspiratoryflowwaveformsonlungmechanics,gasexchange,andrespiratorymetabolisminCOPDpatientsduringmechanicalventilation.Chest2002;122:2096-2104COPD吸氣氣流波形MechanicalVentilationofCOPD/Asthma|BinDuYangSC,YangSP.Effectsofinspiratoryflowwaveformsonlungmechanics,gasexchange,andrespiratorymetabolisminCOPDpatientsduringmechanicalventilation.Chest2002;122:2096-2104COPD患者機(jī)械通氣的最佳吸氣氣流為減速氣流Vt,TI和Pplat相似的情況下，PIP更低正常肺泡過(guò)度牽張的風(fēng)險(xiǎn)減小高壓報(bào)警減少，從而確保潮氣量通過(guò)選擇適宜的吸氣氣流，有可能改善患者的通氣Vt恒定時(shí)的呼吸頻率MechanicalVentilationofCOPD/Asthma|BinDuTuxenDV,LaneS.Theeffectsofventilatorypatternonhyperinflation,airwaypressures,andcirculationinmechanicalventilationofpatientswithsevereair-flowobstruction.AmRevRespirDis1987;136:872-879延長(zhǎng)TE：

Flowvs.

RRVtRRFlowTtotTITEΔTE0.515304.001.003.00–0.515604.000.503.500.500.514304.301.003.300.30MechanicalVentilationofCOPD/Asthma|BinDuVtRRFlowTtotTITEΔTE0.515604.000.503.50–0.5151204.000.253.750.250.514604.300.503.800.30OddoM,FeihlF,SchallerM,etal.Managementofmechanicalventilationinacutesevereasthma:practicalaspects.IntensiveCareMed2006;32:501-510延長(zhǎng)TE的有效方法取決于吸氣流量基礎(chǔ)值VE≈10lpm且TE>4”時(shí)延長(zhǎng)TE的作用MechanicalVentilationofCOPD/Asthma|BinDuLeathermanJW,McArthurC,ShapiroRS.Effectofprolongationofexpiratorytimeondynamichyperinflationinmechanicallyventilatedpatientswithsevereasthma.CritCareMed2004;32:1542-1545COPD機(jī)械通氣：外源性PEEP6名重度氣道梗阻患者PEEP5–15cmH2OVEI,FRC,Pplat相應(yīng)升高Peso,CVP升高，CO和MAP降低MechanicalVentilationofCOPD/Asthma|BinDuTuxenDV.Detrimentaleffectsofpositiveend-expiratorypressureduringcontrolledmechanicalventilationofpatientswithsevereairflowobstruction.AmRevRespirDis1989;140:5-9COPD機(jī)械通氣：外源性PEEPMechanicalVentilationofCOPD/Asthma|BinDuCaramezMP,BorgesJB,TucciMR,etal.Paradoxicalresponsestopositiveend-expiratorypressureinpatientswithairwayobstructionduringcontrolledventilationCritCareMed2005;33:1519-1528COPD機(jī)械通氣：外源性PEEPMechanicalVentilationofCOPD/Asthma|BinDuCaramezMP,BorgesJB,TucciMR,etal.Paradoxicalresponsestopositiveend-expiratorypressureinpatientswithairwayobstructionduringcontrolledventilationCritCareMed2005;33:1519-1528COPD機(jī)械通氣：外源性PEEPMechanicalVentilationofCOPD/Asthma|BinDuCaramezMP,BorgesJB,TucciMR,etal.Paradoxicalresponsestopositiveend-expiratorypressureinpatientswithairwayobstructionduringcontrolledventilationCritCareMed2005;33:1519-1528COPD機(jī)械通氣：外源性PEEPMechanicalVentilationofCOPD/Asthma|BinDuCaramezMP,BorgesJB,TucciMR,etal.Paradoxicalresponsestopositiveend-expiratorypressureinpatientswithairwayobstructionduringcontrolledventilationCritCareMed2005;33:1519-1528COPD機(jī)械通氣：外源性PEEPMechanicalVentilationofCOPD/Asthma|BinDuCaramezMP,BorgesJB,TucciMR,etal.Paradoxicalresponsestopositiveend-expiratorypressureinpatientswithairwayobstructionduringcontrolledventilationCritCareMed2005;33:1519-1528COPD機(jī)械通氣：外源性PEEPMechanicalVentilationofCOPD/Asthma|BinDuCaramezMP,BorgesJB,TucciMR,etal.Paradoxicalresponsestopositiveend-expiratorypressureinpatientswithairwayobstructionduringcontrolledventilationCritCareMed2005;33:1519-1528COPD機(jī)械通氣：外源性PEEPMechanicalVentilationofCOPD/Asthma|BinDuCaramezMP,BorgesJB,TucciMR,etal.Paradoxicalresponsestopositiveend-expiratorypressureinpatientswithairwayobstructionduringcontrolledventilationCritCareMed2005;33:1519-1528對(duì)于部分氣道梗阻的患者而言,應(yīng)用控制通氣過(guò)程中,設(shè)置外源性PEEP能夠緩解過(guò)度充盈基礎(chǔ)疾病,機(jī)械力學(xué)指標(biāo)或呼吸機(jī)設(shè)置均無(wú)法預(yù)測(cè)上述結(jié)果逐漸增加PEEP并觀察平臺(tái)壓力改變,是減少副作用的合理方法COPD機(jī)械通氣：外源性PEEPMechanicalVentilationofCOPD/Asthma|BinDuGuerinC,Milic-EmiliJ,FournierG:EffectofPEEPonworkofbreathinginmechanicallyventilatedCOPDpatients.IntensiveCareMed2000；26:1207-1214.對(duì)于COPD患者>40%的吸氣肌力用于克服autoPEEP外源性PEEP能夠減少觸發(fā)吸氣所需的吸氣肌力，并改善人機(jī)協(xié)調(diào)性COPD機(jī)械通氣：外源性PEEPAECOPD控制通氣過(guò)程中不宜應(yīng)用外源性PEEP一旦自主呼吸恢復(fù)，應(yīng)使用低水平PEEP保證患者舒適不超過(guò)autoPEEP降低觸發(fā)功MechanicalVentilationofCOPD/Asthma|BinDuAECOPD/哮喘機(jī)械通氣初始設(shè)置呼吸參數(shù)設(shè)置模式VCV分鐘通氣量<10lpm潮氣量6–10ml/kgPBW呼吸頻率10–14bpm平臺(tái)壓<30cmH2O吸氣流量60–80lpm吸氣流量波形減速氣流呼氣時(shí)間4–5sPEEP0cmH2OFIO2SaO2>90%MechanicalVentilationofCOPD/Asthma|BinDuOddoM,FeihlF,SchallerM,etal.Managementofmechanicalventilationinacutesevereasthma:practicalaspects.IntensiveCareMed2006;32:501-510COPD自主呼吸時(shí)呼氣觸發(fā)靈敏度MechanicalVentilationofCOPD/Asthma|BinDuTassauxD,GainnierM,BattistiA,etal.Impactofexpiratorytriggersettingondelayedcyclingandinspiratorymuscleworkload.AmJRespirCritCareMed2005;172:1283-1289COPD自主呼吸時(shí)呼氣觸發(fā)靈敏度MechanicalVentilationofCOPD/Asthma|BinDuTassauxD,GainnierM,BattistiA,etal.Impactofexpiratorytriggersettingondelayedcyclingandinspiratorymuscleworkload.AmJRespirCritCareMed20