CASE DISCUSSIONBRONCHIAL ASTHMA

BRONCHIAL ASTHMAChronic Inflammatory disorder of bronchi characterized by Episodic, reversible bronchospasm resulting from an exaggerated bronchoconstrictor response to various stimuli (allergy)

ASTHMA--PATHOGENETIC TYPESExtrinsic (Allergic/Immune)Atopic - IgEOccupational - IgGA. Bronchopulomonary Aspergillosis - IgEIntrinsic (Non immune)Aspirin inducedInfections induced

AETIOLOGYFACTORS WHICH MAY PREDISPOSE TO ASTHMA:Childhood infections e.g respiratory syncytial virusAllergen exposureIndoor pollutionDietary deficiency of anti-oxidants Exposure to pets in early life

FACTORS WHICH MAY PROTECT AGAINST ASTHMALiving on farmsLarge familiesChildhood infections including parasitesPredominance of lactobacilli in gut flora

PRECIPITATING AGENTS

PATHOPHYSIOLOGY

PRESENTATION OF ASTHMAACUTE SEVERE ASTHMAAcute Severe AsthmaLife threatening AsthmaNear Fatal Asthma

PRESENTATION OF ASTHMACHRONIC STABLE ASTHMA:Mild Intermittent asthmaMild Persistent Moderate PersistentSevere persistent

CLASSIFICATION OF SEVERITY OF CHRONIC ASTHMAMILD INTERMITTENTMILD PERSISTENTMODERATE PERSISTENTSEVERE PERSISTENT

CLINICAL FEATURESSYMPTOMSFeeling of chest tightnessEpisodes of dyspneaNon-productive cough which aggravates dyspneaWheeze

SIGNS:TachycardiaTachypneaBreath sounds vesicular with prolongedexpirationAudible wheezeWidespread polyphonic wheezeHyper-inflated chestHyper-resonant percussion note

FEATURES OF ACUTE SEVERE ASTHMAPEF 33-50% predicted(25/minHeart rate >110/minInability to complete sentences in one breath

LIFE-THREATENING FEATURESPEF

NEAR FATAL ASTHMARaised PaCO2 and/or requiring mechanical ventilation with raised inflation pressures

DIFFERENTIAL DIAGNOSISCOPDAcute bronchitisPneumothoraxLarge airway obstructionLeft ventricular failurePulmonary embolismSVC obstructionExtrinsic allergic alveolitis

INVESTIGATIONSCHRONIC ASTHMA:

BLOOD CPABSOLUTE EOSINOPHIL COUNTSERUM IgE LEVELCHEST X-RaySPIROMETRY FEV1 FEV1/FVC, RV REVERSIBILTY TEST EXERCISE TESTPEF MONITORINGHISTAMINE or METHACHOLINE CHALLENGE TESTSKIN PRICK TESTCULTURE FOR FUNGAL HYPHAE

INVESTIGATIONSACUTE ASTHMA:ABGsPEFSPUTUM CULTURECHEST X-RAYBLOOD CPCRP

DIAGNOSIS OF ASTHMACompatible Clinical history plus either/or:

FEV1 > 15%(and 200ml)increase following administration of a bronchodilator/corticosteroids

>20% diurnal variation on > 3 days in a week for 2 weeks on PEF diary

FEV1 > 15% decrease after 6 minutes of exercise

MANAGEMENT

GOALS OF ASTHMA MANAGEMENTAchieve and maintain control of symptomsPrevent asthma exacerbationMaintain pulmonary function as close to normal as possibleAvoid adverse effects from asthma medicationPrevent development of irreversible airflow limitationPrevent asthma mortality

MANAGEMENT OF CHRONIC ASTHMA.STEP WISE APPROACHSTEP1: Occasional use of INHALED SHORT ACTING b-2 ADRENOCEPTOR AGONIST

STEP2Low dose INHALED CORTICOSTEROIDS (or other anti-inflammatory agents)

STEP--3Low to moderate dose INHALED CORTICOSTEROIDS plus LONG ACTING INHALED b-2 ADRENOCEPTER AGONIST or LEUKOTRIENE RECEPTOR ANTAGONIST

STEP--4High dose INHALED CORTICOSTEROIDS and REGULAR BRONCHODILATORS

STEP--5Addition of regular ORAL CORTICOSTEROID therapy

STEP DOWN TREATMENTOccasional temporary step ups will be needed to control exacerbationConsider step down if good symptom control for 3 or more months Withdraw anti-inflammatory treatment if patient well for atleast 6 months

PRECAUTIONARY MEASURES FOR ASTHMATICSDust control measures at homesAvoid wall to wall carpetingAdequate air ventilationDont keep pets at homesAvoid smokingDont keep flowers and plants in rooms

ContdCockroach control measuresAvoid physical exercise in case of exercise induced asthmaAvoid perfumes and spraysAvoid eatables which aggravate asthma

THE REALITY Asthma is not yet curable *Under-diagnosed & Under-managedTherapy is still evolving HOPE Better understanding of PathologyNew line of Promising Drugs.Proper management normal life.