支气管哮喘(双语).ppt

Asthma ZhongminQiuDepartmentofRespiratoryMedicineTongjiHospitalofTongjiUniversity WhatIsAsthma Asthmaisadiseasethatcharacterizedby AirwayobstructionthatisreversibleeitherspontaneouslyorwithtreatmentchronicairwayinflammationIncreasedairwayresponsivenesstoavarietyofstimuliInflammationcausesrecurrentepisodesofwheezing breathlessness chesttightnessandcoughing particularlyatnightorearlymorning Epidemiology 17 20millionAmericans 6 10 prevalence 1 estimatedprevalenceinmainlandofChina10millionmedicalvisits2millionemergencyvisits0 5millionhospitalization5000deathsannuallyMajorcauseofschoolandworkabsenceAtleast12billionperyearIncreasingburdenforyears ImpactOfAsthmaOnPatients Psychosocial Poorself esteemAnxietyaboutasthmaFearofbecomingillatout doorAnxietyaboutexerciseFearofbeingdifferent DidYouKnow Asthmakillspeopleequallyregardlessofseveritylevel1 3ofdeathsareinthosewithmildasthma1 3ofdeathsareinthosewithmoderateasthma1 3ofdeathsareinthosewithsevereasthma WhatCausesAsthma Asthmamaybecausedbygenetic immuneand orenvironmentalfactors andisoftenassociatedwitheczemaandallergiesWedonotunderstandallofthecausesofasthmaoritsincreasingprevalenceItboilsdownto Wejustdon treallyknowforsure WhatCausesAsthma Ofthe17millionasthmasufferersintheUS 10Million approx 60 haveallergicasthma 3millionofthosearechildrenExposuretocertainallergenstriggerasthmasymptomstobeginExposuretocertainirritantscanalsosetanasthmaepisodeinmotion TriggersandIrritants CommonAllergens Triggers SeasonalPollensAnimaldandersaliva urineDustMitesCockroaches Mice RatdroppingsandurineMoldSomemedicationsSomeFoods CommonIrritants Triggers ExerciseColdAirChalkDustViral upperrespiratoryinfectionsAirpollutionTobaccosmokeorsecondhandsmoke ChemicalirritantsandstrongsmellsStrongemotionalfeelingsDieselfumesCleaningsupplies RV InducedAirwayInflammation VirusescauseasthmaexacerbationsRVscause 60 ofvirus inducedexacerbationsofasthmaRVsdirectlyinfectthebronchialairwaysTheresponsetoviralinfectionisshapedbythehost santiviralresponse RV InducedAsthma Nakano Y etal Chest2002 122 271S a 275S a Pathophysiologicschemaforthedevelopmentofasthma TheAllergicReaction TheAsthmaCascade MediatorPhases Early phasereactioncausedbymediatorrelease usuallypeakswithinanhourafterinitialexposuretotheallergen Threetofourhoursafteranacuteasthmaepisode a late phasereaction mayoccurandmaylastupto24hours TheEndResultsOfTheCascade LocalizedmucosaledemainthewallsofthesmallbronchiolesSecretionofthickmucusintothebronchiolarlumens Clogsandnarrowstheairways Spasticcontractionofbronchiolarsmoothmuscle NormalBronchioleInflamedBronchiolewithMucus AirwayObstruction Copyright3MPharmaceuticals2004 RemodelingPhases Airwaywallthickening SubepithelialfibrosisSmoothmusclehyperplasiaandhypertrophyMyofibroblasthyperplasiaMucusmetaplasia Vignola A M etal Chest2003 123 417S a 422S a Increasedthicknessofthebasementmembrane arrow andenhancedandabnormaldepositionoffibronectin whichisidentifiedbyimmunohistochemistryusingaspecificmonoclonalantibody dashedarrow inthebronchialsubmucosa Increasedthicknessofthebasementmembrane andenhancedandabnormaldepositionofcollageninthebronchialsubmucosa ALotGoingOnBeneathTheSurface CommonSymptomsOfAsthma Frequentcough especiallyatnightShortnessofbreathorrapidbreathingChesttightnessChestpainWheezingFatigue EarlySignsOfAnAsthma Episode MildcoughDropinPeakFlowreadingItchy wateryorglassyeyesItchy scratchyorsorethroatRunnynose StomachacheHeadacheSneezingCongestionRestlessnessDarkcirclesundereyesIrritability MeasuresOfAssessmentAndMonitoring TwoAspects InitialassessmentanddiagnosisofasthmaPeriodicassessmentandmonitoring InitialAssessment DiagnosisofAsthma DeterminesThat PatienthasahistoryorpresenceofepisodicsymptomsofairflowobstructionAirflowobstructionisatleastpartiallyreversibleAlternativediagnosesareexcluded MethodsforEstablishingDiagnosis DetailedmedicalhistoryPhysicalexam wheezeandrhonchus rhonchi Spirometrytodemonstratereversibility Diagnosisofasthma Objectivemeasurements 20 diurnalvariationon 3daysinaweekfor2weeksonPEFdiaryorFEV1 15 and200ml increaseaftershortacting 2agonistorsteroidtabletsorFEV1 15 decreaseafter6minutesofrunningexercisehistamineormethacholinechallengeindifficultcases Symptoms episodic variable wheezeshortnessofbreathchesttightnesscough Signsnone common wheeze diffuse bilateral expiratory inspiratory tachypnea Helpfuladditionalinformationpersonal familyhistoryofasthmaoratopyhistoryofworseningafteraspirin NSAID blockeruserecognisedtriggers pollens dust animals exercise viralinfections chemicals irritantspatternandseverityofsymptomsandexacerbations Considerthediagnosisofasthmainpatientswithsomeorallofthesefeatures AsthmaLungAssessmentSpirometry SpirometryisGoldstandardtoassistinasthmadiagnosisPerformedbeforeandafterbronchodilatordosetolookforairwayobstructionreversibilityCanalsobedonewithhistamineormethylcholinechallenge oranexercisechallengeinthecaseofexercise inducedasthma IsAirflowObstructionAtLeastPartiallyReversible UsespirometrytoestablishairflowobstructionFEV115 andatleast200mLafterusingashort actinginhaledbeta2 agonist PeakExpiratoryFlowVariability AnanotherwaytoevaluateairwayobstructionThereisthedifferencebetweenthemorningandeveningPEFreadingsPEFreadingstendtobehigherintheeveningthaninthemorning PeakFlowMeters Differentialdiagnosisofasthma Someofsymptomsofasthmaaresharedwithdiseasesofothersystems Numerousrelativelycommonlungdiseases Needtodifferentiatefrominfectionsandrestrictivelungdisorders andbetweenlocalandgeneralisedobstruction AsthmaSeverityLevels MildIntermittentMildPersistentModeratePersistentSeverePersistent AsthmaSeverityLevelsBySymptoms MildIntermittent Sx2x weekbut2nights monthModeratePersistent SxeverydaySx 1night weekSeverePersistent ContinualdaytimeSxFrequentSxatnight MildIntermittent Symptoms 2days weekwithnighttimesymptoms 2nights monthAsymptomaticwithnormalpeakflowsbetweenexacerbationsExacerbationsarebrief hourstoafewdays PeakFlows 80 predictedwithvariability 20 MildPersistent Symptoms 2days weekbut 1x daywithnighttimesymptomsgreaterthan2nights monthExacerbationsmayaffectactivityPeakflow 80 predictedwithvariabilityof 20 30 ModeratePersistent ChildislikelytohavedailysymptomsanduserelieverdailyChildiswakingupatleastonceaweekduetoasthmasymptomsPeakflows60 80 ofpredictedwithvariabilityof 30 Activityisaffectedandexacerbationsmaylastdays SeverePersistent ContinualdaytimesymptomswithfrequentnighttimesymptomsVerylimitedphysicalactivityFrequentexacerbationsPeakflows 60 ofpredictedandvariabilityofmorethan30 Treatmentinvolvesacombinationofmanydrugtherapies GoalsOfAsthmaTherapy PreventchronicandtroublesomesymptomsMaintain normal pulmonaryfunctionMaintainnormalactivitylevels includingexerciseandotherphysicalactivityMinimizetheneedforemergencyroom urgentcarevisitsorhospitalizations GoalsOfAsthmaTherapyContinued PreventrecurrentexacerbationsofsymptomsProvideoptimalpharmacotherapywithminimalornoadverseeffectsSatisfythepatient sandthefamily sgoalsforasthmacare StepwiseApproachToAsthmaTherapy Outcome BestPossibleResults BronchodilatorsRelaxingbronchialsmoothmuscletoopenuptheairway Anti inflammatoryagentsInhibitingthedevelopmentofairwayinflammationandstoppingongoinginflammation Incombination treatandpreventreversibleairwayobstructionandairwayhyperresponsiveness relievethesymptomanddecreasetheexacerbation Comm