Airway ObstructionRespiratory Distress Syndrome, AdultRespiratory Distress Syndrome, NewbornIntestinal ObstructionAirway ResistanceLungUreteral ObstructionLung Diseases, ObstructiveRespiration, ArtificialRespiratory Function TestsForced Expiratory VolumeLaryngeal DiseasesAsthmaTracheal StenosisPositive-Pressure RespirationPulmonary SurfactantsSpirometryAirway RemodelingInfant, NewbornVital CapacityBronchiTidal VolumeRespiratory MechanicsAcute Lung InjuryNasal ObstructionRespiratory SystemBronchoalveolar Lavage FluidBronchial DiseasesPulmonary VentilationBronchoscopyPulmonary Gas ExchangeRespiratory InsufficiencyTracheal DiseasesBronchitisIntubation, IntratrachealLung CompliancePierre Robin SyndromeBarotraumaDuodenal ObstructionBronchial HyperreactivityInfant, PrematureLung Volume MeasurementsPlethysmography, Whole BodyMaximal Expiratory Flow-Volume CurvesLung DiseasesTracheotomyBronchodilator AgentsBronchoconstrictionPulmonary Disease, Chronic ObstructiveAdministration, InhalationUrinary Bladder Neck ObstructionUrethral ObstructionProne PositionRespiratory MucosaBronchial Provocation TestsPulmonary EdemaGastric Outlet ObstructionDyspneaPulmonary AlveoliStress, PsychologicalBlood Gas AnalysisHigh-Frequency VentilationTotal Lung CapacityTreatment OutcomeLarynxLung InjuryPulmonary EmphysemaRespiratory Dead SpaceVentricular Outflow ObstructionRespirationOxygenLaryngostenosisResidual VolumeFunctional Residual CapacityAlbuterolAerosolsFatal OutcomePulmonary Surfactant-Associated Protein BHeliumAir PressureProspective StudiesSeverity of Illness IndexPulmonary AtelectasisContinuous Positive Airway PressureHigh-Frequency Jet VentilationPneumoniaForced Expiratory Flow RatesRespiration DisordersTomography, X-Ray ComputedPeak Expiratory Flow RateIntubationRespiratory SoundsTracheaLaryngeal EdemaHorse DiseasesMaximal Expiratory Flow RateRespiratory HypersensitivityRetrospective StudiesCoughAcute Disease