Respiratory Distress Syndrome, AdultFetal Organ MaturityRespiratory Distress Syndrome, NewbornAmniotic FluidLungInfant, NewbornPulmonary SurfactantsHyaline Membrane DiseaseRespiration, ArtificialSphingomyelinsAcute Lung InjuryPositive-Pressure RespirationSyndromeBarotraumaTidal VolumeInfant, PrematureGestational AgePrenatal DiagnosisInfant, Newborn, DiseasesPregnancyProne PositionLung InjuryHigh-Frequency VentilationPulmonary Gas ExchangeAmniocentesisPhosphatidylglycerolsPhosphatidylcholinesLung DiseasesPulmonary Surfactant-Associated Protein BTerm BirthPulmonary AlveoliFluorescence PolarizationLung ComplianceBronchoalveolar Lavage FluidPulmonary EdemaExtracorporeal Membrane OxygenationRespiratory Dead SpaceAnimals, NewbornPregnancy in DiabeticsInfant, Premature, DiseasesBlood Gas AnalysisRespiratory MechanicsVentilator-Induced Lung InjuryRespiratory InsufficiencyOxygenBronchopulmonary DysplasiaBiological ProductsVentilators, MechanicalPhospholipidsIntensive Care UnitsOxygenators, MembraneRespiratory AspirationFatty AlcoholsAPACHEMultiple Organ FailurePneumoniaProspective StudiesSepsisPulmonary Surfactant-Associated Protein CPneumothoraxIntensive Care Units, NeonatalTreatment OutcomePulmonary Surfactant-Associated ProteinsLung Volume MeasurementsExtravascular Lung WaterFatal OutcomeIntensive Care, NeonatalCritical CareChromatography, Thin LayerPulmonary AtelectasisPartial PressureRadiography, ThoracicIntensive CarePulmonary Surfactant-Associated Protein ARetrospective StudiesPulmonary CirculationAdministration, InhalationBetamethasoneLung NeoplasmsSurface TensionAcute DiseaseCritical IllnessInfant, Very Low Birth WeightTime FactorsRisk FactorsRespiratory Function TestsOxygen Inhalation TherapyProteolipidsAdrenal Cortex HormonesInfant, Low Birth WeightSmoke Inhalation InjuryBirth WeightTuberculosis, MiliaryBronchoalveolar LavagePneumonia, AspirationSeverity of Illness IndexLeukomalacia, PeriventricularIntubationIntubation, IntratrachealHemodynamics