Mesenteric Vascular OcclusionMesenteric Artery, SuperiorMesenteric ArteriesEmbolismFlank PainPulmonary EmbolismSuperior Mesenteric Artery SyndromeMesenteric Artery, InferiorCeliac ArteryArteriesEmbolism, FatSplanchnic CirculationDuodenostomyRenal ArteryPulmonary ArteryMesenteric VeinsSplenic ArteryEmbolism, ParadoxicalAngiographyTomography, X-Ray ComputedIntracranial EmbolismVasodilationVasoconstrictionMuscle, Smooth, VascularHepatic ArteryCerebral ArteriesIntracranial Embolism and ThrombosisCarotid ArteriesFemoral ArteryVasoconstrictor AgentsAneurysmEmbolism, Amniotic FluidBasilar ArteryVasodilator AgentsDuodenal ObstructionReperfusion InjuryIschemiaIliac ArteryRats, WistarBiological FactorsTreatment OutcomeEndothelium, VascularRenal VeinsNorepinephrineConstriction, PathologicUltrasonography, DopplerPhenylephrine