Pulmonary Disease, Chronic ObstructiveBronchodilator AgentsScopolamine DerivativesForced Expiratory VolumeRespiratory Care UnitsSputumAdrenal Cortex HormonesDisease ProgressionCholinergic AntagonistsDyspneaHospitalizationVital CapacitySeverity of Illness IndexRespiratory Function TestsAlbuterolAdministration, InhalationSpirometryMetered Dose InhalersAcute DiseasePulmonary InfarctionTreatment OutcomeAdrenergic beta-2 Receptor AgonistsProspective StudiesOxygen Inhalation TherapyQuality of LifeLungAsthmaEthanolaminesDouble-Blind MethodSmokingDrug CombinationsRetrospective StudiesAnti-Inflammatory AgentsBronchitis, ChronicLung Diseases, ObstructiveAnti-Bacterial AgentsRecurrenceBiological MarkersQuestionnairesTime FactorsLength of StayRespiration, ArtificialPrognosisBronchitisRisk FactorsExpectorantsPicornaviridae InfectionsAnti-Asthmatic AgentsPractice Guidelines as TopicCohort StudiesComorbidityRhinovirusHospital MortalityHealth StatusC-Reactive ProteinFollow-Up StudiesPulmonary MedicineInflammationNeutrophilsCystic FibrosisPeak Expiratory Flow RateBronchiectasisBudesonideNebulizers and VaporizersRespiratory Tract InfectionsRespiratory System AgentsExercise TolerancePulmonary EmphysemaStatus AsthmaticusAndrostadienesGlucocorticoidsRespiratory InsufficiencyRespiratory TherapyIpratropiumAdrenergic beta-AgonistsCommon ColdVirus DiseasesChronic DiseaseInhalation SpacersIdiopathic Pulmonary FibrosisDrug Therapy, CombinationPhosphodiesterase 4 InhibitorsBronchiExhalation