老年病学教学课件：Respiratory Failure in the Elderly

RespiratoryFailureintheElderlyLearningObjectives※Veryimportant:Definitionanddiagnosticstrategyofrespiratoryfailureintheelderly.※Important:Causeandpathophysiologyofrespiratoryfailureintheelderly.※Lessimportant:Treamentofrespiratoryfailureintheelderly.ContentsDefinitionandtypesofrespiratoryfailure(RF)1

PathophysiologyofRFinelderlypatients2

DiagnosisofRFinelderlypatients3

TreatmentofRFinelderlypatients4DefinitionDefinedasinadequategasexchangeduetopulmonaryornon-pulmonarycausesleadingtohypoxemia,hypercapniaorboth.Respiratoryfailure(RF)DocumentedbyPaO2<60mmHgassociated

ornotwith

PaCO2>50mmHgAtsealevel,breathingroomair[FIO2=0.21]thenormalanatomicshuntTypesLungfailureRespiratoryfailureGasexchangefailuremanifestedbyhypoxaemiaPumpfailureVentilatoryfailuremanifestedbyhypercapniaTherespiratorysystemcanbesaidtoconsistoftwoparts:Thelungthegas-exchangingorganIngeneral,failureofthelungcausedbyavarietyoflungdiseases(e.g.pneumonia,emphysemaandinterstitiallungdisease)leadstohypoxaemiawithnormocapniaorhypocapnia

(hypoxaemicortypeIrespiratoryfailure).Thepumpconsistsofthechestwall,includingtherespiratorymuscles,therespiratorycontrollersinthecentralnervoussystem(CNS)andthepathwaysthatconnectthecentralcontrollerswiththerespiratorymuscles(spinalandperipheralnerves).Failureofthepumpresultsinalveolarhypoventilationandhypercapnia(hypercapnicortypeIIrespiratoryfailure).typeIfailuremaybecomplicatedbyrespiratorypumpfailureandhypercapnia.typeIIfailuremaybecomplicatedbyseverehypoxemiaduetosecondarypulmonaryparenchymalprocesses(eg,pneumonia,atelectasis,pulmonaryedema),orvasculardisorders(pulmonaryembolism).∗RFindicatesrespiratoryfailure.ThedistinctionbetweentypeIandtypeIIRFmustnotbeviewedasrigid.Fig.1.–RelationbetweenPO2andPCO2tensionwhenbreathing.Theslopeofthelinedependsontherespiratoryexchangeratio;inthisexample,itisassumedtobe0.8.ArterialPO2(..........)islessthanalveolarPO2;thedifferenceassumedhereis5mmHg.A-C:directionofchangesinalveolargastensionsinvariouslungdiseases.AcuteonchronicrespiratoryfailureTypesRespiratoryfailure

AcuteRFdevelopswithinminutesorhoursChronicRFdevelopsoverseveraldaysorlongerInthecaseofhypercapnicfailure,thepresenceof

adequaterenalcompensationindicateschronicRFPresenceofmarkersofchronichypoxemiapolycythemia,

corpulmonaleprovidescluestochronicdisorder,whereas

abruptchangesinmentalstatussuggestanacuteoran

acute-on-chronicevent∗RFindicatesrespiratoryfailure.AcuteversuschronicrespiratoryfailureContentsDefinitionandtypesofrespiratoryfailure(RF)1

PathophysiologyofRFinelderlypatients2

DiagnosisofRFinelderlypatients3

TreatmentofRFinelderlypatients4PhysiologicalchangesaccordingtoagePulmonaryfunctionDecreasingchestwallcompliancewithageCardiovascularchangesThedecreaseofmyocytenumber,intrinsiccontractilitycoronaryflowreserve,ventricularcomplianceandß-adrenoceptormediatedmodulationofinotropy.Cardiacandrespiratorysystemsaredependent.Forexample,(1)aboutofpneumoniaissufficienttotriggeranacuteexacerbationofheartfailure,(2)areductionincardiacoutputaccompanyingsepticshockisacauseofARFcausedbydiaphragmhypoperfusionleadingtoalveolarhypoventilation,andrespiratoryarrest.PhysiologicalchangesaccordingtoageOtherrelevantchangesPhysiologicalchangesaccordingtoageDecreaseinglomerularfiltrationrate(approximately45%bytheageof80)withageinghasimportantimplicationsintermsofdrugdosing,asmostdrugsarerenallyexcreted.Imbalancebetweenprocoagulant/antifibrinolyticandanticoagulantfactors,whichcouldcontributetoanincreasedincidenceofPE.Otherrelevantchanges

Hypoxicdrive

Ventilatoryresponse

non–rapideyemovement(NREM)sleep

rapideyemovement(REM)sleep

ResponsetoPaCO2FallminuteventilationTheaccompanyingfallinoxygensaturationandriseinPaCO2fromthismechanismisgreatlyexaggeratedinpatientswithdisease,whichcanleadtonocturnalhypoventilation.PrincipalcausesofacuterespiratoryfailureInelderlypatients,majorcauseofhypoxaemicARF-anemergencysetting(CHForPneumonia)-increasedshunt(ARDS)-alveolarhypoventilation(COPD)diffusionimpairment(pulmonaryfibrosis)MajorcauseofhypercapniaARFseverehyperinflation,withflatteneddiaphragmand-reducedmechanicalactionoftheinspiratorymuscles(COPDexacerbation)Increasedofintrapulmonaryshunt(ARDS)DiffusepulmonaryinfiltratesHypoxemicrespiratoryfailure(typeI)Hypercapnicrespiratoryfailure(typeII)DifficultdiagnosisofRFintheelderlyClinicalandLaboratoryManifestation

(non-specificandunreliable)DyspneaCoughFever

Deliriumatadmissionwasverycommon(45%)

wasobservedinonly32%ofpatientswithCAPAtypicalsignsofCHFarefrequent(confusionorlegswelling,or

wheezing),andconfusing.※※TheclinicalmanifestationsofpatientswithRFdependinlargepartontheunderlyingdisease,whiletheconsequencesofhypoxiaandhypercapniaarenonspecificandhavealreadybeenpresented.Patientswithrespiratorydistress,inadditiontodemonstratinglaboredrespirationtachypneaanddyspnea,oftenexhibitdiaphoresis,tachycardia,andtremulousness.Speechisoftenbrokeninto2-or3-wordsentences.ItshouldbenotedthatpresenceofdyspneaisnotequatedwithRFandisnotaprerequisiteforRF.Dyspneaatrestmaybeabsentincertainpatientswithventilatoryfailure(forexamplepatientswithobesity-hypoventilationsyndrome,kyphoscoliosis,hypothyroidismorcoexistenceofCOPDwithsleep-apnea).EtiologyofARFEtiologyofARF*Halfofthepatientshadmorethantwodiagnoses(CHFandCAPin17%).Pneumothorax,lungcancer,severesepsisandacuteasthmawerelessfrequent(<5%).*Amisseddiagnosisintheemergencydepartmentwasnotedin101(20%)patients.Theaccuracyofthediagnosisoftheemergencyphysicianrangedfrom0.76forcardiogenicpulmonaryedemato0.96forasthma.Aninappropriatediagnosisisassociatedwithanincreasedmortality*Aninappropriatetreatmentoccurredin162(32%)patients,andleadtoahighermortality(25%versus11%;p<0.001).*Inamultivariateanalysis,inappropriateinitialtreatment(oddsratio2.83,p<0.002),hypercapnia>45mmHg(oddsratio2.79,p<0.004),clearanceofcreatinine<50mlminute-1(oddsratio2.37,p<0.013),elevatedNT-pro-B-typenatriureticpeptideorB-typenatriureticpeptide(oddsratio2.06,p<0.046),andclinicalsignsofacuteventilatoryfailure(oddsratio1.98,p<0.047)werepredictiveofdeath.DiagnosticstrategyofARFintheelderlyUnknowndiagnosesPreviouscardiacorlungdiseaseBNPOrNT-proBNPMedicalHistory,physicalfindings,CXR,ABG,EKGObviousdiagnosisCHF,CAP,ACS…SuspectedCHF100BNP500BNP100pg/mlBNP500pg/mlCHFunlikelyRespiratorydisorders?PossibleCHFDopplar-echocardiographyCHFverylikelyNitrateIVbolus,diuretics,ACEi,NIV,Doppler-ECFurtherinvestigationsCTchestwithparenchymalwindows,thenprotocolePEorlungultrasonographyHowcouldweimproveoutcomesofARFinelderlypatients?UsefulnessoftransthoracicechocardiographyRoleofB-typenatriureticpeptidesInflammatorymarkers(biologicalmarkerssuchasCreactiveprotein

(CRP)andprocalcitonin(PCT)maybeusefultosuggestbacterial

infection)PotentialusefulnessofthoracicimagingPrevalenceofcausesofCRFPatientswithkyphoscoliosisandaneuromusculardiseasehadthelongestsurvival(8and6.5years,respectively)—atleastinpartbecauseofyoungerageandfewercomorbidities.PatientswithCRFduetotuberculosisexperiencethesamesurvivalaspatientswithCOPD.Prognosisisworstinpatientswithpneumonoconiosisorfibrosis.50%percentofthesepatientsdieduringtheyearfollowingthebeginningofhometreatment.RespiratoryFailureAnOverviewManagementofrespiratoryfailureTherapeutictargetsinRFReversionofunderlyingpathologyandofcontributing

orprecipitatingfactors.Reversionofunderlyingpathophysiologicmechanisms

(increasedelasticorresistiveload,atelectasis,etc)Oxygentherapy:arterialhypoxemiaisthemostlife-

threateningabnormalityinRF,andincreasingSaO2to

85%–90%shouldhavethehighestprioritywhen

managingARF.Reduceoxygenrequirements:fever,agitation,overfeeding,

vigorousrespiratoryactivity,andsepsiscanmarkedly

decreaseoxygenconsumptionOptimizationofoxygentransportthroughinterventionsin

cardiacoutputorredcelltransfusionAvoidanceofiatrogeniccomplications(overinflation,

ventilator-inducedlunginjury,oxygentoxicity)TherapeutictargetsinRFNowadays,long-termoxygentherapy(LTOT)andmechanicalventilationareoftenusedinelderlypatientseitherinacuteorinchronicsituationstocontrolARFepisodesandtostabilizeCRFonalong-termbasisathomeorinlong-termcarefacilities.Noninvasivemechanicalventilation(NIV),whichrepresentsthedeliveryofventilatorysupportwithoutuseoftheendotrachealroutebutviaabuccal,nasal,orperithoracicprosthesis,hasgainedamajorroleinthemanagementofARFandCRFofvariousetiologies.TreatmentofARF1.MedicalandsocialaspectComplexchronicillnessesDailytreatmentspolymedicationAmulti-disciplinarycaremodel2.OxygentherapySupplementalO2therapyessentialtitrationbasedonSaO2,PaO2levelsandPaCO2GoalistopreventtissuehypoxiaTissuehypoxiaoccurs(normalHb&C.O.) -venousPaO2<20mmHgorSaO2<40%

-arterialPaO2<38mmHgorSaO2<70%IncreasearterialPaO2>60mmHg(SaO2>90%)O2doseeitherflowrate(L/min)orFiO2(%)TreatmentofARFRisksofOxygenTherapyInjudicioususeofoxygentherapyisassociatedwithincreasedhypercapniainCOPDpatientsAimatprovidinganoxygensaturation>90%,andcheckbloodgases

30minafterstartingoxygeninCOPDpatientsWhenO2isgiventothehypercapnicpatientwithRF(especiallyat

FiO2>0.3),PaCO2usuallyrises(becauseofworseningV/Qrelationshipsandcancellationofthehypoxicdrivetobreath).Uncontrolledoxygenadministrationmaythusprecipitatehypercapniccoma.HypoxemiaandacidosisaremorepredictiveforCO2narcosisthanistheabsolutevalueforPaCO2.TreatmentofARF3.ManagementofpneumoniaintheelderlyTreatmentofARF►ImportantroleofsilentaspirationandthelowprevalenceofLegionellasp.,ChlamydiaandMycoplasmapneumoniaeinCAP.StreptococcuspneumoniaeisthemostcommoncauseofCAPintheelderly.►Gram-negativebacilli(Klebsiella,Proteussp,Escherichiacoli,andothers)accountforhalfofalltheculture-diagnosedpneumoniasinnursing-homeacquiredpneumonia.►Recommendationsforanti-microbialdrugusedependonthesuspectedspecificorganism,andguidelines.Themainobjectiveistostartantibioticsasearlyaspossiblesinceantibioticadministrationwithin4hofhospitalarrivalisassociatedwithalower30-daymortality.TreatmentofARF4.PharmalogicaltreatmentofCHFMedicaltreatmentsofCHFconsistedofdiuretics,andmorphineNitrateandarteriodilatationACEIorARBTreatmentofARF5.Potentialroleofnon-invasiveventilationbyafacemaskLowerratesofendotrachealintubationDecreasednumberofventilatordays

ShorterstaysintheICUReductioninmortalityandotheretiologiesofacutehypercapnicRF.EarlyinterventionwithNIVappearstobethekeytosuccess.AcuteCardiogenicPulmonaryEdemaAcuteexacerbationsofCOPD(AECOPD)PneumoniaEnd-of-LifeSituationsTreatmentofCRFTreatmentofCRFInvasivemechanicalventilationInvasivemechanicalventilationisaveryaggressiveinterventionthatusuallysucceedstosustainsomeonethroughRF,butleavesthepatientvulnerabletomanycomplications(barotrauma,sepsis,stressulceration,acuterenalfailure,nosocomialpneumonia,etc)DuetotheMV-associatedcomplicationsintheolderelderly.thephysicianmustalwaysfacetheethicalquestionofwhetherMVprovidesameaningfulandsuccessfuloutcomeormerelylengthenstheprocessofdying.InvasivemechanicalventilationCausesofARFintheelderlyareoftendifficulttodiagnose.AmisdiagnosisintheEDisassociatedwithincreased

morbidityandmortality.CPEwasthemaincauseofARFinelderlypatientsToevaluatetheseverityofillnessofelderlypatientswith

ARF,physiciansshouldfocusonavailablecriteria:

PaCO2,creatinineclearance,levelsofBNPorNTproBNP,

andclinicalsignsofacuteventilatoryfailure.KeypointsNIVisassociatedwithlessdiscomfort,fewercomplications,andbettershort-termresultsthanisendotrachealventilation(ETV).Recentprogressinthetechnologyofmasks,respirators,oxygensources,andhomecareserviceshavemadelong-termNIVmorereadilyavailableforolderpatientswithRF.KeypointsCase

one73-year-oldretiredengineer;

Presentswith:Chestpainfor8hoursCombinedwithbackpainNauseaandvomitingHistoryoftype2diabetesWhatdoyouask?

PhysicalExamGeneral:InpainBP90/60,P92,RR20,T37H&N:nonystagmus,nobruitsChest:kyphosis,noaddedbreathsoundsCardiac:NormalS1,S2,nomurmurAbdo:Nopulsations,nomasses,tenderNeuro:NormalcranialnervesInvestigationsBloodtestCBC:WBC12.07X10^9/L,N90.9%,Hb159g/L,Plts150X10^9/LNa144.0mmol/L,Kmmol/L,BUN9.94mmol/L,Creatinine109.0umol/LABG:PH7.372,PCO236.3mmHg,PO244mmHg,SaO281.1%HCO3-

21.1mmol/LBNP231.00pg/mlCK-MB273.5ng/ml

,MYOG1768.9ng/ml,cTn-I63.24ng/mlEKG:NormalSinusRhythm,90bpm,ST-segmentelevationof2to3mmintheinferiorleads(II,III,andaVF)andinleadsV1throughV4.ChestX-ray:

bilateraldiffuseexudation;pleuraleffusionsUCG:

markedmotionabnormalitiesintheanteriorwallandanteriorseptuminferiorposterior;

muralthrombosis;dysfunctionofpapillarymuscle;moderateandseveremitralregurgitation.ChestX-ray2015.9.242015.10.82015.10.27UCGDiagnosisAextensiveanteriorandinferiormyocardialinfa