Femoral VeinCatheters, IndwellingCatheterization, Central VenousJugular VeinsSubclavian VeinCatheterization, PeripheralVeinsCathetersSaphenous VeinPopliteal VeinIliac VeinVaricose VeinsCatheterizationPortal VeinPhlebographyVenous InsufficiencyVenous ValvesSwineVenous ThrombosisPulmonary VeinsUltrasonography, Doppler, DuplexInsulinRats, Sprague-DawleyMesenteric VeinsThighLegFemoral ArteryThrombophlebitisHepatic VeinsCentral Venous CathetersVena Cava, InferiorEquipment FailureCardiac CathetersVascular PatencyVascular MalformationsCardiac CatheterizationUrinary CatheterizationArteriovenous Shunt, SurgicalVenous PressureVascular Surgical ProceduresUmbilical VeinsRenal VeinsTreatment OutcomeEquipment DesignThrombosisUrinary CathetersTime FactorsDogsVascular GraftingVena Cava FiltersVaricose UlcerPulmonary EmbolismVascular NeoplasmsBlood Flow VelocityLower ExtremityCatheter-Related InfectionsPhlebotomyRegional Blood FlowCentral Venous PressureBandagesRenal DialysisConstriction, PathologicBlood Vessel ProsthesisProspective StudiesCerebral VeinsSplenic VeinBrachiocephalic VeinsHeart AtriaUltrasonography, Doppler, ColorAzygos VeinFollow-Up StudiesPolytetrafluoroethyleneDissectionRetrospective StudiesGraft Occlusion, VascularPostthrombotic SyndromeLigationPolyethylene TerephthalatesAxillary VeinBlood Vessel Prosthesis ImplantationHemodynamicsAnastomosis, SurgicalCadaverRetinal Vein