Cerebral VentriclesSubarachnoid HemorrhageSubarachnoid SpaceCerebrospinal FluidPerfusionInjections, IntraventricularBlood PressurePressureCerebral HemorrhageCisterna MagnaFourth VentricleHemorrhageVasospasm, IntracranialIntracranial PressureCerebral ArteriesHeart VentriclesCerebrovascular CirculationBrainCerebrospinal Fluid ProteinsShiveringHydrocephalusIntracranial AneurysmDogsCerebral AngiographyIntracranial HemorrhagesInjectionsCerebral InfarctionPerfusion ImagingBody TemperatureCerebrospinal Fluid PressureTime FactorsLateral VentriclesAneurysm, RupturedEpendymaRegional Blood FlowCatsMiddle Cerebral ArteryTomography, X-Ray ComputedRats, Sprague-DawleyNorepinephrineHeart RateHypothalamusHemodynamicsBrain IschemiaThird VentricleRats, WistarHydrostatic PressurePempidineSpinal PunctureChoroid PlexusBody Temperature RegulationIntracranial HypertensionBasilar ArteryRetinal HemorrhageBlood Flow VelocityPhysostigmineMagnetic Resonance ImagingHypnosis, AnestheticCerebral Ventricle NeoplasmsCoronary CirculationCerebrospinal Fluid ShuntsCerebrospinal Fluid RhinorrheaVascular ResistanceHexamethonium CompoundsConsciousnessSerotoninIntraocular PressureTranylcypromineLaser-Doppler FlowmetryHypertensionCerebral PalsyMyocardial Perfusion ImagingMeningitisHeartCerebral VeinsInjections, IntravenousRabbitsPhentolamineVasoconstrictionDisease Models, AnimalPostpartum HemorrhageArachnoidTreatment OutcomeHistamine AgentsCerebral VentriculographyPyrogensRats, Inbred StrainsDose-Response Relationship, DrugIschemic Attack, TransientVentriculostomyProspective StudiesGastrointestinal HemorrhageVitreous HemorrhageBlood VolumeRenal CirculationGlasgow Outcome ScaleBrain EdemaBrain InjuriesVenous PressureAtropine