Blood Gas AnalysisPlacentaCarbon DioxideOxygenAcid-Base ImbalanceGasesPartial PressureCapnographyPulmonary Gas ExchangeBlood Gas Monitoring, TranscutaneousOximetryRespiratory InsufficiencyHepatopulmonary SyndromeRespiratory Dead SpaceRespirationHypoventilationRespiratory Function TestsBlood Specimen CollectionMethemoglobinemiaVentilation-Perfusion RatioAcid-Base EquilibriumPlacenta DiseasesOxygen ConsumptionHypercapniaAnoxiaPlacenta PreviaOxyhemoglobinsPlacenta AccretaRespiration, ArtificialHydrogen-Ion ConcentrationOxygen Inhalation TherapyPlacenta, RetainedLungPregnancyAnesthesia, GeneralPulmonary EmbolismRadiography, ThoracicExercise TestLung DiseasesSpirometryPulmonary Disease, Chronic ObstructiveProspective StudiesPositive-Pressure RespirationHemodynamicsBicarbonatesArteriesVital CapacityTrophoblastsForced Expiratory VolumeAcute DiseaseHeart RateObesity Hypoventilation SyndromeTime FactorsSyringesMaternal-Fetal ExchangeBlood PressureSwineRetrospective StudiesLung Diseases, ObstructiveChorionic VilliChromatography, GasPoint-of-Care SystemsPulmonary VentilationGas Chromatography-Mass SpectrometryTreatment OutcomePredictive Value of TestsNoble GasesDisease Models, AnimalFetusPregnancy ProteinsCardiac OutputPlacentationExercise ToleranceMonitoring, PhysiologicIntensive CareBreath TestsInfant, NewbornGestational AgeDyspneaPre-EclampsiaRespiratory Distress Syndrome, AdultLactic AcidGas Poisoning