Regional Blood FlowPulmonary CirculationBlood Flow VelocityMicrospheresPulmonary ArteryVascular ResistanceHemodynamicsPulmonary Gas ExchangeCardiac OutputCerebrovascular CirculationVentilation-Perfusion RatioDogsLungBlood PressureGravitationSheepOxygenBlood Gas AnalysisBlood CirculationSplanchnic CirculationCoronary CirculationHeart Bypass, RightLaser-Doppler FlowmetryRenal CirculationHypertension, PulmonaryHeart RateHeart Defects, CongenitalScandiumLiver CirculationCarbon DioxidePartial PressureOxygen ConsumptionXenon RadioisotopesSupine PositionNoble GasesTechnetium Tc 99m Aggregated AlbuminFractalsVasoconstrictionProne PositionNitric OxideAnoxiaOxygenatorsSwineTomography, Emission-ComputedFontan ProcedureModels, CardiovascularAnesthesiaVasodilationBlood VolumeVasodilator AgentsKrypton RadioisotopesHypoplastic Left Heart SyndromeNitric Oxide SynthaseOxygen RadioisotopesHeart Septal Defects, VentricularNitrogen RadioisotopesExtravascular Lung WaterMicrocirculationRadioisotopesTime FactorsFlow CytometryBrainPulmonary VeinsArteriovenous Shunt, SurgicalPulmonary AtresiaFetusCollateral CirculationNafronylAortic Arch SyndromesHindlimbPhentolamineKidneyDisease Models, AnimalRespirationGravity SuitsCapillariesPulsatile FlowRats, Sprague-DawleyIschemiaOrganotechnetium CompoundsRespiration, ArtificialVena Cava, SuperiorPulmonary Diffusing CapacityPostureLung Volume MeasurementsPulmonary EdemaSheep, DomesticPulmonary Valve StenosisPulmonary VentilationNG-Nitroarginine Methyl EsterRenal ArteryLegDuctus ArteriosusHeartMagnetic Resonance ImagingRestIliac ArteryImmersionTurtlesCyanosis