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MechanicalVentilationinChronicObstructivePulmonaryDisease TimOp tHolt Ed D R R T ProfessorCardiorespiratoryCareUniversityofSouthAlabamaMobile Alabama DiscussionPoints DeterminingtheneedforventilationNoninvasiveversusinvasiveventilationInstitutingnoninvasiveventilationInstitutinginvasiveventilationManagingventilationDrugdeliveryduringmechanicalventilationManagingauto PEEPWeaningthepatient DeterminingtheNeedforVentilation HypercapnicrespiratoryfailurePathophysiologicdeterioration AcuteHypercapnicRespiratoryFailure PaCO2 50mmHgwithapH 7 3 lowPaO2normalP A a O2CNSdepression neuromusculardiseasehypopnea somnolence comahypoxemiacausedbyhypoventilationand orlowV Q ExamplepH7 20PaCO263mmHgPaO248mmHgHCO3 24mEq LSaO272 ChronicHypercapnicRespiratoryFailure PaCO2 50mmHgNearnormalpH duetorenalcompensationCommoninCOPDNotanindependentindicationforventilation ExamplepH7 38PaCO270mmHgPaO262mmHgHCO3 41mEq LSaO290 AcuteonChronicRespiratoryFailure PaCO2 50mmHgpH 7 3 insufficientrenalcompensationSeverehypoxemiaExacerbationofCOPD oftenwithpneumoniaVentilationindicated ExamplepH7 25PaCO282mmHgPaO235mmHgHCO3 35mEq LSaO240 PathophysiologicDeterioration Mechanicalventilationisconsideredwhenphysiologicindicatorsexceednormalranges NoninvasiveversusInvasiveVentilation ConsiderNoninvasiveVentilationAcuteexacerbationofCOPDRespiratoryacidosis pH7 25 7 35 despiteoptimaloxygenandmedicaltherapyAbletoprotectairwayConsciousandcooperative HemodynamicallystableNIVmaybeaceilingfortherapyifintubationisnotanoptionSecretionsmaylimittheeffectivenessofNIPPVinbronchiectasis NoninvasiveversusInvasiveVentilation ConsiderInvasiveVentilationTheairwaycannotbeprotected patientissemiorunconscious Life threateninghypoxemiaSeverecomorbidity heartfailure Confusion agitation CopiousrespiratorysecretionsFocalconsolidationonchestradiographSevereacidosis pH 7 25 PatienthasnoteethPoornutritionalstatus InstitutingNoninvasiveVentilation NoninvasiveventilatorPressurecontrolledPIPupto30cmH2OFlowupto60L minA CandBiPAPRateupto40bpmFlowtriggeredDisconnectalarm InstitutingNoninvasiveVentilation OxygenAddedatornearthemaskFromseparateflowmeterHumidificationNotnormallynecessaryAlarmsPressure flow and orvolume InstitutingNoninvasiveVentilation NasalmasksAfterfirst24hoursGelcushionedmasksFullfacemasksUsedforfirst24hoursNasalpillowsChinstrap HowtoSetupNoninvasiveVentilation DecidewhattodoifNIVfailsDeterminesiteofNIVtrialExplaintopatientFitafacemaskandholditonthepatientSetuptheventilatorAttachapulseoximeterCommenceNIV holdingthemaskinplaceSecurethemaskinplacewiththeheadgear ReassessafterafewminutesAdjustsettingsasnecessaryAddoxygenifSpO2 85 InstructthepatienthowtoremovethemaskandsummonhelpReassessandobtainABGin1 2hoursAdjustsettingsasnecessaryInstitutealternativemanagementplan Setting uptheNoninvasiveVentilator Mode SpontaneousortimedEPAP 4 5cmH2OIPAP 12 15cmH2OTrigger maximumsensitivityBackuprate 15breaths minuteBackupI Eratio 1 3 AdjustingNIVSettings PaCO2elevatedOxygenmaybesettoohighLeaksinthecircuitRebreathing checkexpiratoryvalve Patient ventilatordyssynchronyAdjustrate trigger IPAP PaCO2OK butPaO2lowIncreaseoxygenflowIncreaseEPAP WhyUseNIVinCOPD TrachealintubationrateissubstantiallyreducedComplications particularlypneumoniaareattributedtointubationReducedneedforintubationDecreasedin hospitalmortalityNointubation relatedcompliactionsFewerICUdaysDecreasedcostofhospitalization InstitutionofInvasiveVentilation AirwayAccess Intubation8 0mmtube22cmatincisors 25cmH2OcuffpressureAssureproperplacementAssuresecurityManuallyventilate Modes FVSvs PVS FVSTotalVET P FtriggeringPC VC CMVSIMVwithnormalratePRVCInadequateVAApnea hypercapnicfailure PVSPartornoVET P FtriggeringLowrateSIMV PSV VSV CPAP APRVHypoxemicorhypercapnicfailure SIMV VCorPCmandatorybreathsCPAPorPSspontaneousbreathsFVSorPVSUsefulthroughoutcourseofventilationMostcommonlyused SetPClevel Time sec SIMV PS CPAP Pressure TargetedVentilation SetPSlevel CPAPlevel SIMV PS CPAP Volume TargetedVentilation SetPSlevel CPAPlevel Time sec PSV F TtriggeredDeliverdesiredVt overcomecircuit ETTresistanceUsedwithSIMVtoincreasespontVTUsedindependentlyforweaningUnloadsventilatorymusclesDecreasesweaningtimeUsedforhypoventilationsyndromes CPAP PSV SetPSlevel Time sec FlowL m PressurecmH2O VolumemL InstitutionofInvasiveVentilation Tidalvolume 8 10mL kgMandatoryrate 8 10breaths minuteInspiratoryflow AllowalongTEPEEP 3 5cmH2OPSV toachieveVTof5mL kgFiO2 0 4Trigger preferablyflow 1 3L min AdjustingVentilatorySupportSettings RateandVolume PaCO2isdeterminedbyVCO2 VA andVd VtTochangePaCO2wechangeVENewVE currentVExcurrentPaCO2desiredPaCO2TodecreasePaCO2 increaseVtfirst thenfToincreasePaCO2 decreasef AdjustingRateandVolume Newrate currentratexcurrentPaCO2desiredPaCO2InCOPD ventilatethepH VentilatoryManagementChallengesinCOPD AirtrappingIncreasedairwayresistanceBronchodilatorresponseAdequacyofinspiratoryflowUsewaveforms AirTrapping Inspiration Expiration Time sec Flow L min AirTrapping Inspiration Expiration Volume ml Flow L min Doesnotreturntobaseline NormalAbnormal Paw cmH2O NormalPPlat NormalCompliance IncreasedPIP IncreasedPTA increasedAirwayResistance IncreasedAirwayResistance IncreasedRaw Pressure cmH2O HigherPTA NormalSlope Vol mL LowerSlope IncreasedAirwayResistance Inspiration Expiration Volume ml Flow L min DecreasedPEFR NormalAbnormal Scoopedout pattern ResponsetoBronchodilator Before Time sec Flow L min PEFR After LongTE HigherPEFR ShorterTE InadequateInspiratoryFlow AdequateFlow Time sec InadequateFlow Paw cmH2O InadequateInspiratoryFlow Flow L min Time sec NormalAbnormal ActiveInspirationorAsynchrony InadequateInspiratoryFlow Paw cmH2O Volume ml NormalAbnormal ActiveInspiration InappropriateFlow DrugDeliveryforMechanicallyVentilatedCOPDPatients BetaadrenergicbronchodilatorsAlbuterolsoln MDILevalbuterolsolnMetaproteranolsoln MDISalmeterolMDIBitolterolsoln MDI AnticholinergicbronchodilatorIpratropiumbromidesolutionandMDICorticosteroidMDIBeclomethasoneBudesonideFlunisolideFluticasoneTriamcinalone MDIUseDuringMechanicalVentilation AerosolDepositionintheETTfromNebulizers EfficiencyvarieswithnebulizerbrandContinuousversusintermittentnebulizationGasflowfromventilatorhasalowerdrivingpressureanddecreasedoutputIfdrivingpressureisrestored intermittentnebulizationisbetterasthereislesswasteNebulizerplacementisimportant VentilatorNebulizerFunction Inspiratory expiratory orcontinuousPartoftheVTisrecompressedtopowerthenebulizer butlowflowresultsinparticlesizeExternalsourcesconfoundthevolumemeasuringdeviceNebulizedmedicationsmayfoultheexhalationvalve2 3nebulizationcyclesmaybenecessaryPerformancevarieswithdiluent brand flowandoperatingpressure NebulizationDuringMechanicalVentilation Procedure PlacedruganddiluentinnebulizerPlacethenebulizerin lineapproximately30cm fromthecircuitYEnsurea6 8L minflowtothenebulizer intermittentlyorcontinuouslyAdjusttidalvolumeto 0 5L inspiratoryflowtoachieveTI TTOT 0 3 NebulizationDuringMechanicalVentilation Procedure AdjustminutevolumeifanexternalgasflowisusedDisableanycontinuousflowthroughtheventilatorAssurenebulizerfunctionRemovethenebulizerfromthecircuitwhenthemedicationisspentRestoreventilatorsettings NebulizerLocation NebulizerOutlet MDIUseDuringMechanicalVentilation Procedure Adjusttidalvolumeto 0 5 inspiratoryflowtoachieveTI TTOT 0 3Assuretheventilatorbreathissynchronizedwiththepatient sinspiratoryeffortShaketheMDIvigorouslyInserttheMDIintoacylindricalspacerchamberintheinspiratorylimbofthecircuitproximaltotheY MDIUseDuringMechanicalVentilation MDIUseDuringMechanicalVentilation Procedure ActuatetheMDItocorrespondwiththeonsetofinspirationbytheventilator4 7puffsmaybenecessaryAllowapassiveexhalationRepeatin20 30secondintervalsCollapse removespacerfromthecircuitRestoreventilatorparameters PEEPinObstructiveLungDisease Despiteoptimalmedicaltherapy 1 3 ofpatientswithCOPDexacerbationrequireintubationandMVVentilatorystrategiesfocusondetectingandtreatingdynamichyperinflationLimitminuteventilation lowfandVT Maximizeexpiratorytime Auto PEEP Increaseintheend expiratorylungvolumeaboveFRCbecauseofdynamicforcesatend expirationAvailableTE timerequiredtoexhaletoFRC PositivePalvthroughoutexpirationduetoelasticrecoilDecreasestriggersensitivityHemodynamicinstabilityLoadsinspiratorymuscles DetectionofAuto PEEP End expiratoryairwayocclusionAuto PEEPmeasurementfeatureDifficultinspontaneouslybreathingpatientsNoteexpiratoryflowscalar Auto PEEPScenarios MinimizingAuto PEEP VentilatorfactorsDecreaseVT setfIncreaseflow TEAddPEEPDiscontinueinspiratoryholdUseIMV spontaneousbreathingmodes PatientfactorsOptimalbronchodilatortherapySteroidsSuctionIncreasedETTsize Weaning PredictorsofReadinessforWeaning P F 150orSaO2 90 onFiO2 0 4 withPEEP 5cmH2OStablehemodynamicsAwakeandalertNoneedforsedatives Hemoglobin 8 10g dLCoretemperature5mL kg WeaningAlgorithm WeaningMethods SpontaneousBreathingTrialsPressureSupportVentilationSIMVNPPV SpontaneousBreathingTrial T piece 5cmH2OCPAP or5 8cmH2OPSV FiO2 0 430 120 SuccessABGsWNLf 35bpmStablecardiovascularstatusNoWOB paradoxicalbreathing diaphoresis oragitationEvaluateforextubation WeaningAlgorithm InvestigateFailuretoWean VentilatorydemandVD VT CO2Anxiety painResistiveloadSecretionsBronchospasm ETTVentilatorydriveOversedationMetabolicalkalosisCNSdepressionObesityhypoventilation ElasticloadautoPEEPCHF p