AlbuterolBronchodilator AgentsIpratropiumNebulizers and VaporizersAdministration, InhalationAsthmaForced Expiratory VolumeAdrenergic beta-2 Receptor AgonistsInhalation SpacersMetered Dose InhalersAdrenergic beta-AgonistsTerbutalineSpirometryBronchoconstrictionAirway ResistanceScopolamine DerivativesBronchial SpasmAerosolsRacepinephrineChlorofluorocarbonsVital CapacityPulmonary Disease, Chronic ObstructivePeak Expiratory Flow RateRespiratory Function TestsMetaproterenolRespiratory Therapy Department, HospitalBronchial Provocation TestsFenoterolDouble-Blind MethodLung Diseases, ObstructiveAtropine DerivativesAerosol PropellantsAnti-Asthmatic AgentsForced Expiratory Flow RatesRespiratory TherapyAirway ObstructionBronchiBeclomethasoneOzone DepletionClemastineMethacholine ChlorideBronchiolitisCross-Over StudiesEthanolaminesInspiratory CapacityReceptors, Adrenergic, beta-2Respiratory SoundsLungAdrenal Cortex HormonesBudesonideMaximal Expiratory Flow RateAntitussive AgentsCholinergic AntagonistsTheophyllineNedocromilIndansBronchoconstrictor AgentsEquipment DesignTracheaAmino AlcoholsTreatment OutcomeCoughAminophyllineFunctional Residual CapacityGlycopyrrolateBronchial HyperreactivityDrug Administration ScheduleDrug IncompatibilityDrug Therapy, CombinationDose-Response Relationship, DrugGlucocorticoidsRespiratory Care UnitsButylaminesDrug CombinationsPlethysmographyParasympatholyticsNasal DecongestantsBronchitisPlacebosOscillometryPulmonary VentilationRespiratory MechanicsResidual VolumeDyspneaMasksTephrosiaQuinolonesTotal Lung CapacityMuscarinic AntagonistsAndrostadienesTime FactorsIntubation, IntratrachealHeliumLung ComplianceSeverity of Illness IndexModels, AnatomicPowdersMyasthenic Syndromes, CongenitalPharmaceutical SolutionsTachyphylaxis