Blood VolumeBlood VesselsPlasma VolumeHypovolemiaErythrocyte VolumeCerebrovascular CirculationHematocritLymphatic VesselsPlasma SubstitutesMagnetic Resonance ImagingHemodynamicsRetinal VesselsRegional Blood FlowStroke VolumeCoronary VesselsBlood PressureFluid ShiftsBlood Flow VelocityCardiac OutputLung Volume MeasurementsBrainContrast MediaBlood CirculationHemorrhagePulmonary Diffusing CapacityOxygenTime FactorsMicrocirculationImage Processing, Computer-AssistedMagnetic Resonance AngiographyReproducibility of ResultsHemodilutionDye Dilution TechniqueHemoglobinsSpectroscopy, Near-InfraredIsotonic SolutionsHydroxyethyl Starch DerivativesDogsPulmonary CirculationShock, HemorrhagicPerfusion ImagingVascular ResistanceTomography, X-Ray ComputedIndocyanine GreenCapillariesBlood Volume DeterminationVascular CapacitanceOxygen RadioisotopesImaging, Three-DimensionalOxygen ConsumptionNeovascularization, PathologicHypotensionHeart RateGadolinium DTPATomography, Emission-ComputedImage Interpretation, Computer-AssistedVeinsSensitivity and SpecificityImage EnhancementSplanchnic CirculationThoraxBrain NeoplasmsPlethysmographyFluid TherapyCapillary PermeabilityExchange Transfusion, Whole BloodCerebral ArteriesCarbon DioxideArteriesOrgan SizeModels, CardiovascularReference ValuesPolygelinePressureBrain IschemiaCentral Venous PressureDisease Models, AnimalColoring AgentsWater-Electrolyte BalanceIndicator Dilution TechniquesAcetazolamideRats, Sprague-DawleyForced Expiratory VolumeLungProspective StudiesLiver CirculationVasoconstrictionDiuresisTechnetiumPostureCarbon MonoxideAlgorithmsTreatment OutcomeEndothelium, VascularSupine PositionBody WaterEcho-Planar ImagingBlood Gas AnalysisVasodilationSaline Solution, Hypertonic