内科学支气管哮喘-陈小东.ppt

BronchialAsthma,Introduction,Bronchialasthmaachronicinflammatoryconditioninvolvingavarietyofcellsincludingeosinophils,mastcells,Tlymphocytes,neutrophils,andepithelialcellsoftheairway,aswellascellularelementswhichgivesrisetotheincreaseofairwayhyper-reactivity.,ExtensivechangeableandreversibleventilationrestrictioniscommonCauserecurrenttachypnea,feelingofoutofbreath,andcoughingThesymptomsaremoreusuallypresentandaggravatedatnightorearlyinthemorningRemissionmightbeachievedspontaneouslyorfollowingtreatment,Epidemiology,160millionpatientsintheworldprevalence：1%-5%，0.5-1%inchinaPrevalenceinmaleissimilartothatinfemaleTheonsetisbefore12yearsofageinthemajorityFamilyhistorycouldbefoundin20%patientsRelatedtoallergicrhinitis,eczemaandnasalpolyp,Etiology,ThepathogenesisofasthmaiscomplicatedAffectedbygeneticsandtheenvironmentItisamultigenedisorderandcloselyrelatedtoatopyMostpatientshavepriorhistoryofeczema,allergicrhinitis,foodordrugallergy,andquiteafewpatientshavefamilyhistoryTheformationandattackofasthmaisalsoaconsequenceofthefunctionofmultipleenvironmentalfactorssuchasinhalationofallergens,respiratorytractvirusinfection,andcoldness,Etiology,Geneticfactors:multigeneinheritanceheritability70-80%Predisposingfactors:airpollution1）inhalants：dustmites、pollen2）infections3）food4）changeofweather5）mentalfactors6）exercise7）drugs8）menstruation,pregnacy,Pathogenicmechanism,AsthmaisCharacteristicofhyper-reactivityoftheairwayChronic（allergic）inflammationisthebasiclesionofasthma,Allergicinflammation,InvestigationshaveshownthatallergicreactionslikeasthmaaremediatedbyTh2cells.ThereisanincreaseorpredominanceofTh2oritscytokines.Theresultingairwayinflammationcouldbeclassifiedintothefollowingtwotypes:1.IgEmediatedandTlymphocytedependentpathway2.NonIgEmediatedandTlymphocytedependentpathway,ImmunologicfactorsTheroleofIgEmediation,ThecombinationofallergenwithspecificIgEtriggersthedegranulationofthemastcellsandeosinophils,resultinginreleaseofmediatorsincludingleukotrienesC,D,E,andthesubsequentsmoothmusclecontraction,edemaofthemucosa,increaseofsecretion,andfinallystenosisofthebronchioles,whichallcontributetoasthma.TotalserumIgEorspecificserumIgEtiterincreaseisseeninpatientswithasthma,indicatingtypeIallergicreactionsmightbepresent.,nonIgEmediated,Tlymphocytedependentpathway,Indelayedtypeallergicreaction,Th2celldirectlyinitiatesimflammatoryresponsebyactivationandagglutinationofvariousinflammatorycellsviathereleaseofmultiplecytokines(IL-4、IL-13、IL-3、IL-5）,Neuromentalfactors,Thecomplicatedautonomicinnervationofthebronchiopulmonarysystemincludescholinergic,adrenergic,nonadrenergicandnoncholinergicnerves.-adrenergicreceptormalfunctionandtheincreasedtoneofthevagus,orwithsimultaneousincreaseof-adrenergicreactivity,wouldpromotecontractionofthesmoothmuscleandsecretionoftheglands,resultinginattackofasthma,Endocrinefactors,Asthmadisappearsinpubertyinsomepatients;aggravatedinmenstruationperiod,duringpregnancy,andwhenthereishyperthyroidism,Hyper-reactivityoftheairway,Bronchialreactivityreferstothecontractivereactionoftheairwaytovariousstimuliincludingthosechemical,physicalorpharmacologicinnature,Pathology,Thebasicpathologyofbronchialasthmaincludesimflammationandremodelingoftheairway.Thebasicpathologicalchangeoftheinflammmationincludesinfiltrationofmastcells,macrophages,eosinophils,lymphocytesandneutrophils;edemaofthesubmucosa,increaseofthepermeabilityofthemicrovasculature,retentionofthesecretionwithinthebronchioles,spasmofthebronchialsmoothmuscle,detachmentofthecilatedepithelium,exposureofthebasalmembrane,poliferationofgobletcellsandincreaseofbronchialsecretion,whichcontributetoformthechroniceosinophilicbronchitis,Clinicalmanifestation,Thetypicalonsetofasthmaisaccompaniedbysneezing,nasalsecretion,coughingandoutofbreath.Iftimelytreatmentisnotgiven,thebronchialnarrowingmightgetworseandcausedsypnea.Inseverecases,thepatientisobligedtotakethesittingpositionwhichisreferedtoasothopnea,coughingwithorwithoutlargeamountofwhitefoamysputum,orevenwithcyanosis.,Clinicalmanifestation,Physicalexamination:Increasedanteroposteriordiameterofthechest,over-resonanceonpercussion,wheezingalloverthechest;whenseveredyspneaexists,bothbreathingsoundsandwheezingcouldbereducedorabsent.Nosymptomsandsignsmightbepresentduringtheintervalofattack,insomecases,wheezingcouldbenotedonexersion,Clincalmanifestation,Symptomsaremoresevereatnight,andcouldberelievedaftermedicationorspontaneously.Whensevereacuteasthmaattackcouldnotbemitigatedwithin24hoursbyappropriateuseofadrenomimetics,thepatientisinthestateofpersistentasthma.Thepatientmightbestrugglingduetodyspneabeforehebecomesweakandunabletocough.Bloodpressuremightdecline,cyanosismightappear,andthepatientmightevendiefromacuterespiratoryfailure.,Lab,Peripheralblood：eosinophilsincrease.Afalsewhitecellcountincreasemightoccurifadrenalineisused.X-ray：over-inflationofthelung;increasedlungmarkings;smallareashadowmightappearalongthebronhchiolesifthereisbronchialpneumonitisoratelectasis,Lab,Lungfunctiontest：decreaseofairflowrateandtidalvolume,increaseofreservevolume.BloodgastestshowsadecreaseinPaO2;aninitialPaCO2declinemaybenotedandanelevationfollowswithprogression.pHdecreasesinthelatestage.duringtheintervalofattack,lungfunctionisusuallynormalexceptthereservevolumeisincreased.DailytestofPEFanditsvarianceishelpfulforthejudgementoftheexistenceofsubclinicalasthma.,Lab,Thesuspectedantigenisusedforskintestsoastofindouttheallergen.Theskinpricktestisquitereliable,diagnosis,DiagnosticcriteriaforasthmaCriteriaforcoughvariantasthma,Diagnoticcriteria,1.recurrentbreathlessness,wheezing,coughing,andtightnessinthechest.Usuallyrelatedtocontactofallergen,coldair,physicalorchemicalstimuli,upperrespiratorytractinfectionwithvirus,andexercise,ect.2.diffuseorscatteredexpiratorywheezingcouldbeheardduringtheattack,theexpiratoryphaseislengthened.3.theabvesymptomsandsignsmightberemittedaftertreatmentorspontaneously.4.othercausesofwheezing,shortofbreath,coughingandtightnessinthechestareexcluded.5.atleastoneofthefollowingtestsispositive,iftheclinincalpictureis（egnowheezingorsigns）：positivebronchialorexercisechallengetestpositivebronchodilatatortestFEV1increasebymorethan15%，andtheincreaseofabsoluteFEV1volume200ml；dailyPEFvarianceor24hourfluctuation20%。when14or4、5aremet，bronchialasthmaisdiagnosed。,Differentialdiagnosis,1.CardiacasthmaAminophylline,morphine,epinephrine2.asthmaticchronicbronchitis3.Bronchiogeniclungcancer4.eosinophiliclungdiseases,Criteriaforcoughvariantasthma,Alsonamedallergiccoughing,whichisapotentialinsidiousformofasthmaandoccursatallagegroup.Itsexclusivesymptomischroniccoughingwithnopositivesigns.Thereforeitmightbemisdiagnosedasbronchitis.Howeveritisbelievedbymostphysiciansthatitsmechanismofpathogenesisisidenticaltothatofasthma,andtreatmentiseffectivewhenmedicationsforasthmaareindicated.,Criteriaforcoughvariantasthma,Recurrentorpersistentcoughingformorethan2monthswithoutmuchsputum,whichoccursatnightorintheearlymorning,andgotworseafterexercise.Noinfectionispresentorlongtermuseofantibioticsprovesnoteffective.Bronchodilatatorscouldreducecoughing（basiccriterium）Historyofallergyorfamilialallergy，airwayishighresponsive,positiveallergenskinpricktest,Staging,Asthmacouldbeclassifiedintothefollowing3stagesaccordingtoitsclinicalpicture:exacerbationphase,persistentphase,andremissionphase.,Evaluationofnon-exacerbationphase,severe：frequentattackofsymptoms,limitedcapability,badsleeping,PEForFEV60ofpredicted,PEFvarience30moderate：dailyattacked,sleepingandabilitycompromised,nocturnalasthmaonceaweek,PEForFEV150，30,Evaluationofnon-exacerbationphase,minor：symptomsonceaweek，butlessthanonceaday.abilityandsleepingmightbeaffected.nocturnalasthmatwiceamonth，PEForFEV180，PEFR2030intermittent：symptomsappearintermittently,12岁）slowed，irregular,ClinicalfeatureminormoderatesevereacutesleepapneaPaCO26possiblerespiratoryfailure（kPa）SaO295919590()pHdecline,Evaluationoftheseverityforacuteattack,Goalofmanagementforasthma,toeffectivelycontrolacuteattackandmaintainminimalsymtomsornosymptomstopreventaggravation；tokeeplungfunctionaroundnormallevel；tomaintaintheabilitytoexercice；toavoidtheadversereactionofthemedicationsforasthma.,Standardsforasthmacontrol,minimal(orno)chronicsymptoms,includingsymptomsatnight.minimaltimesofasthmaattack；noemergencyroomvisitduetoasthmaminimaluseof2antagnists；nolimitationofability(includingexercise).（6）24hourPEFvariance20；(7)PEFnormaloralmostnormal；(8)minimaladversereactionsofmedications,Eliminationofetiology,Avoidallergen,appropriatetreatmentofinfection,eradicateexposuretothepredisposingfactors(smoking,paint,icecream,abruptchangeofweather),Asthma:Prevention,StopsmokingDecreaseETSexposureReduceexposuretobiologicaldustReduceexposuretopollutionReducerisktorespiratoryvirusesDietary:IncreaseantioxidantsandOmega3sDecreaseexposuretocowsmilk,dairy,nuts,soy,wheatininfancy,Asthma:Treatment,RemovetheallergenDrugTherapyBronchodilators(Foracuteresponses)Adrenocorticolhormone:dangeroussideeffectsifusedlongtermPsychosocialTechniquesStressManagementSocialSupport,WhatsNewforTreatingAsthma?,Medications:longtermorcontrollermedicationsquickreliefmedicationsSteppedtherapy:starthigh,backdownAsthmamonitoringandactionplansEnvironmentalcontrols,OverviewofMedications,ControllermedicationscontrolinflammationlongdurationbronchodilationmultiplenewmedicationsQuickreliefmedicationsforintermittentorbreakthroughsymptomsControversy:Useworsensasthma?Markerofworseningasthma?,ControllerAgents,InhaledcorticosteroidsSystemiccorticosteroidsLongacting2agonistsCromolynandderivativesMethylxanthinesLeukotrieneModifiers,InhaledCorticosteroids,ControlairwayinflammationlocallyIdeal:controlasthma(highlocalpotency);nosideeffects(lowsystemiceffects)fluticasone,budesonidebeclomethasone(triamcinolone,flunisolide),SystemicCorticosteroids,MaybeneededinitiallySideeffectprofilewell