RespiratoryFailure第一頁，共四十九頁。編輯課件1.AbstractsRespiratoryfailure,whetheracuteorchronic,isafrequentlyfacedproblemandamajorcauseofdeathinourcountry.Forexample,mortalityfromCOPD,whichendsindeathfromrespiratoryfailure,continuestoincrease.Morethan70%ofthedeathsinpatientswithpneumoniaareattributedtorespiratoryfailure.第二頁，共四十九頁。編輯課件2.DefinitionRespiratoryfailureisfunctionalacuteorchronicdisordercausedbyanyconditionthataffectsthelung’sabilitytomaintainarterialoxygenationorcarbondioxide(CO2)elimination.Itisdefinedasaconditioninwhichthisgasexchangedeterioratesbelowtheusuallevel,sothatarterialoxygentensiondecreases,withorwithoutanabnormalriseinarterialcarbondioxidetension.第三頁，共四十九頁。編輯課件3.ClassificationsGenerallybothacuteandchronicrespiratoryfailuremaybedividedintotwomaincategories:第四頁，共四十九頁。編輯課件TypeⅠrespiratoryfailureTypeⅠrespiratoryfailureisalsocalledhypoxicrespiratoryfailure,whichmeansthatseverelyreducesarterialoxygentension(PaO2<60mmHg),CO2retentionisnotexist.Thistypeofrespiratoryfailureiscausedbyafailureofgasexchange.第五頁，共四十九頁。編輯課件TypeⅡrespiratoryfailureTypeⅡrespiratoryfailureisalsomeantthathypercapnic-hypoxicrespiratoryfailure.Arterialbloodgasvaluesshowsthatarterialcarbondioxidetensionismorethan50mmHgandarterialoxygentensionislessthan60mmHgTypeⅡrespiratoryismainlycausedbyhypoventilation.第六頁，共四十九頁。編輯課件PathogenesisMainlydiscusschronicrespiratoryfailurewehaveknownthatthelungs’abilityisgasexchange.Thegasexchangeinvolvesnotonlyoxygenationbutalsocarbondioxideelimination.第七頁，共四十九頁。編輯課件PathogenesisRespiratoryfailureismainlyassociatedwithpulmonarygasexchangeandpulmonaryventilation.第八頁，共四十九頁。編輯課件

1.pulmonarygasexchangeismainlydeterminedbyventilation-perfusion(V/Q)ratiosanddiffuseability

V/Qmismatch:AneffectivelunggasexchangeneedsnotonlysufficientlungventilationandlungbloodvolumesbutalsoanadequateV/Qratios.Usually,thevolumeofventilationis4liters/min.Thevolumeoflungbloodis5liters/min.Sotheratiosis0.8第九頁，共四十九頁。編輯課件Anyofthefactorsinfluencedtheratiosmaymainlycausehypoxemiarespiratoryfailure.Forexample,V/Q>0.8,includingemphysema,pulmonaryembolism.V/Q<0.8,includingatelectasis,severeCOPD.第十頁，共四十九頁。編輯課件DiffuseabilityDiffusionabnormalitymainlyinfluenceoxygenexchange.第十一頁，共四十九頁。編輯課件2.PulmonaryhypoventilationItmaycausehypercapnic-hypoxicrespiratoryfailure.Pulmonaryhypoventilationincludesrestrictivehypoventilationandobstructivehypoventilation.Somediseasesinfluencedcentralnervoussystem,peripheralnervoussystem,chestwallrespiratorymusclesandpulmonarycompliancemayallcauserestrictivehypoventilation.第十二頁，共四十九頁。編輯課件SomecommonconditionsthatmaycauseventilatoryfailurewithhypercapneaTheseconditionsincludebrainstemlesion,alteredneuromusculartransmission(guillain-barresyndrome),muscleweakness(malnutrition,shock,hypoxemia,hypokalemia),increasedairwayresistance(upperairwayobstruction,increasedbronchialsecretionsandedema),decreasedlungcompliance(infection,atelectasis,interstitialfibrosis,acutelunginjury),decreasedchestwallcompliance(chestwalltrauma,pleuraleffusion,pneumothorax).第十三頁，共四十九頁。編輯課件COPDandasthmaarethemostcommondiseaseassociatedtoobstructivehypoventilation.Inourclinicalwork,multifactorsinvolveinthecourseofrespiratoryfailure.Forexample,aCOPDpatientwithseverepulmonaryinfection,hispulmonarygasexchangeabilityandpulmonaryventilationareallabnormal.第十四頁，共四十九頁。編輯課件PathophysiologyHypoxiaandhypercapnicmayinfluencefunctionsofmanyimportantorgansandsystems,includingrespiratorysystem,cardiovascularsystem,centralnervesystem,bloodsystemanddigestivesystemandrenalfunction.第十五頁，共四十九頁。編輯課件ClinicalmanifestationsClinicalsignsincludenotonlysymptomsassociatedwithprimarydiseasesbutalsothosecausedbyhypoxicandhypercapnic-hypoxicrespiratoryfailure.Hypoxemiaandhypercapniamainlyinfluencethefunctionofimportantorgans,includingrespiratorysystem,centralnervoussystem,cardiovascularsystem,digestivesystem,renalfunctions.第十六頁，共四十九頁。編輯課件Theunbalanceofacid-alkalosemetabolicanddielectricabnormalityareusuallyexistinthecourseofrespiratoryfailure.Table1.Clinicalmanifestationsofhypoxiaandhypercapnia.第十七頁，共四十九頁。編輯課件

ClinicalmanifestationsofhypoxiaandhypercapniaHYPOXEMIAHYPERCAPNIA

TachycardiaSomnolenceTachypneaLethargyAnxietyRestlessnessAlteredmentalstatusSlurredspeechConfusionHeadacheCyanosisAsterixisHypertensionPapilledemaHypotensionComaBradycardiaSeizuresLacticacidosist第十八頁，共四十九頁。編輯課件DiagnosisAccordingtohistory,clinicalmanifestations,physicalexaminationsandbloodgasanalysis,wecandiagnoserespiratoryfailure.Especiallyarterialbloodgasanalysismayrevealhypoxemiaandhypercapnia.第十九頁，共四十九頁。編輯課件DiagnosisThediagnosisstandardinclude:TypeⅠrespiratoryfailure:PaO2<60mmHgTypeⅡrespiratoryfailure:PaCO2>50mmHg,PaO2<60mmHg.Intheconditionofoxygentherapy,PaO2/FiO2<300mmHgindicatesrespiratoryfailure.第二十頁，共四十九頁。編輯課件TreatmentTheprincipleoftreatmentincludesprimarydiseasetreatment,airwaymaintenance,correctionofhypoxemiaandhypercapniaandmanagementofsymptomscausedbyhypoxemiaandhypercapnia.第二十一頁，共四十九頁。編輯課件(1)AirwaymaintenanceandenhancethevolumeofventilationAssuranceofanadequateairwayiskeyinthepatientwithrespiratoryfailure.Forpatientswithchronicrespiratoryinsufficiency,theneedforintubationdependsoncriticalarterialbloodgasvaluesandthepatientsearlyacutecourse.Whenprogressivehypoxemiaorhypercapniaisobserved,intubationandmechanicalventilationareused.第二十二頁，共四十九頁。編輯課件Tomostofthechronicrespiratoryfailure,correctlyuseofbronchodilatorsisveryimportant.

Table2.BronchodilatorsRouteDoseAlbuterolMDIandspacer400-600gq1-4hAerosolsolution2.5-7.5mgq1-4hIpratropiumMDIandspacer80-120gq4-6h第二十三頁，共四十九頁。編輯課件Mechanicalventilation

Theaimofmechanicalventilationistoimprovehypoxemiaandtopreventhypercapnia.Whendoyouselectmechanicalventilation?TgressiveelevationinPaCO2>70-80mmHg2.severehypoxemia,afteroxygentherapy,PaO2<40mmHg3.respiratoryrates>35perminuteorseverebreathlessness4.severemetabolicacidosisorpulmonaryencephalopathy第二十四頁，共四十九頁。編輯課件(2)AntiinfectioustherapyRepeatedbronchialandpulmonaryinfectionisamajorcauseofchronicrespiratoryfailure.About90%ofCOPDpatientswithrespiratoryfailureiscausedbyacutebronchialorpulmonaryinfection.InfectionmayalsoincreasebronchialsecretionandCO2production.Soantiinfectioustherapyisanimportantmethodtotreatrespiratoryfailure.第二十五頁，共四十九頁。編輯課件SelecteffectiveantibioticsAccordingtosputumculture,wecanselectsensitiveantibioticsUsingcombinedantibioticsBecauseofmultibacteriainfection,itneedsseveralkindofantibiotics.Forexample,wemaycombinesecondorthirdgenerationcephalosporintoaminoglycosideorfluoroguinolone.第二十六頁，共四十九頁。編輯課件(3)OxygentherapyThegoalofoxygentherapyistoimprovePaO2.ItmakesPaO2>60%.Ingeneral,thelowestFiO2achievingadequateoxygenation.sometimes,arterialoxygensaturation>90%shouldbeused.第二十七頁，共四十九頁。編輯課件Themethodsofoxygentherapy:nasalprongs1-3L/mintochronicrespiratoryfailureventimask1-3L/minFortype1respiratoryfailure,wecanelevatethepercentageofoxygentomaintainthePaO2.Wecanusehigherinspiratedfrationofoxygenintype1respiratoryfailureoxygentherapy.Butintype2respiratoryfailurewemustselectlowerinspiratedfrationofoxygen.第二十八頁，共四十九頁。編輯課件(4)Acid-baseandelectrolytesdisturbanceTherearemanyfactorsleadtoacid-baseandelectrolytesdisturbance.Thesefactorsincludeseverepulmonaryinfection,hypoxemiaor(and)hypercapnia.Soairwaymaintenance,antibiotictherapyanduseofbronchodilatorsarebeneficialtotreatit.第二十九頁，共四十九頁。編輯課件(5)Useofrespiratorystimulantdrugs第三十頁，共四十九頁。編輯課件(6)CorticosteroidsMethyprednisoneisusuallyusedtoreducetheairwayinflammation,andtoimproveFEV!.Thetreatmentisrecommendedinallpatientsbutitisnotusedforalongertime.第三十一頁，共四十九頁。編輯課件(7)GastrointestinalbleedingtreatmentBecauseofhypoxemia,hypercapniaandbyusingcorticosteroids,gastrointestinalbleedingalwaysbehappened.Thetreatmentmathodincludecorrecthypoxemiaandhypercapnia,useofH2-blockerandsomeblockbleedingdrugs.第三十二頁，共四十九頁。編輯課件(8)Nutritionalsupporttherapy第三十三頁，共四十九頁。編輯課件AcuteRespiratoryDistressSyndromeARDS第三十四頁，共四十九頁。編輯課件1.DefinitionARDS,whichisafromofacutelunginjuryoftenseeninpreviouslyhealthypatients,ischaracterizedbyrapidrespiratoryratesandasensationofprofoundshortnessofbreath,andaccompaniedbyseverearterialhypoxemia.第三十五頁，共四十九頁。編輯課件2.PathogenesisARDScanresultfrommanydisorders,includingsystemicorpulmonaryinfection,(viral,bacterial,fungal,ects.),aspiration,inhalationoftoxins,metabolicdisordersandseveresepsisorsepticshock.Theinitialinsultcausereleaseofcytokines,mediatorsfromcellmembranesandactivationofanumberofcascadeswithinjurytothepulmonaryendothelium.第三十六頁，共四十九頁。編輯課件ARDSisinvariablyassociatedwithincreasedliquidinthelungs.Itisaformofpulmonaryedema,distinctsfromcardiogenicpulmonaryedema.Sincehydrostaticpressurearenotelevated.第三十七頁，共四十九頁。編輯課件3.ClinicalmanifestationsTheearlymanifestationsareanincreasedrespiratoryrates.Usuallyrespiratoryratesaremorethen28perminute.Sometimesthepatientmaybefreeofrespiratorysigns.Coughandsputumproduction.Becauseofseverehypoxemia,cyanosisisacommonphysicalsignsinARDSpatients.第三十八頁，共四十九頁。編輯課件X-rayshowsaprogressive,usuallysymmetrical,fluffyalveolarinfiltratethatprogressestoinvolveallpotionsofthelung.X-rayfeaturesofARDSmaybedividedintothreestages:Firststage-sometimesnormal,sometimessmallpatchesmaybeexistSecondstage-diffusedsmallorlargepatches,usuallyinlowerlungfieldThirdstage-pulmonaryinfiltrateinvolvedallpotionsofthelung,called‘whitelung’ArterialbloodgasanalysisshowsPaO2/FiO2<300mmHgandPaO2<60mmHg.(ALI),PaO2/FiO2<200mmHg(ARDS)第三十九頁，共四十九頁。編輯課件4.DiagnosisThereisadisorderwhichmayleadtoARDS.Forexample,severeinfectionects.Accordingtoclinicalmanifestation,X-ray,arterialbloodgasanalysis,wecanmakeadiagnosis.第四十頁，共四十九頁。編輯課件Themaindiagnosisstandardincludes:AfactorwhichmayleadstoARDSTheonsetisacute.Tachypneaisexist.HypoxiaChestX-rayshowspulmonaryinfiltrateinvolvedtwolungs.PCWP<=18mmHgorexceptcardiogenicpulmonaryedema.第四十一頁，共四十九頁。編輯課件5.TreatmentTreatmentofinitialdisorderswhichleadtoARDSImprovehypoxemiaSeverearterialhypoxemiaisacharacteristicclinicalsignofARDS.Ingeneral,thelowestinspiredfrationofoxygen(FiO2)shouldbeusedtogivethedesiredresult.TherearemultiplemeansfordeliveringO2,includingsoftnasalprongs,simplefacemasks.ButintheconditionofARDS,thesemethodsarenoteffective.Mechanicalventilatorysupportshouldbeusedearlytoimprovehypoxemia.第四十二頁，共四十九頁。編輯課件UseofPEEPPEEPmeanspositiveendexpiratorypressure.第四十三頁，共四十九頁。編輯課件UseofPEEPThephysiologiceffectsofPEEPinclude:1.redistributionofcapillarybloodflow,resultinginimprovedV/Qmatching;2.Therecruitmentofpreviouslycollapsedalveoliandpreventionoftheircollapseduringexhalation.第四十四頁，共四十九頁。編輯課件Anothertreatmentsaresimilartothosechronicrespi