Supine PositionSkullProne PositionSkull BasePatient PositioningPostureHeadSkull NeoplasmsSkull Base NeoplasmsSkull FracturesHead and Neck NeoplasmsTilt-Table TestHead-Down TiltHeart RateSupinationHypotension, OrthostaticGravitationNephrostomy, PercutaneousHead MovementsBlood PressureRespiratory MechanicsSkull Fracture, DepressedAutonomic Nervous SystemRespirationIndoraminFemur HeadValsalva ManeuverMovementParietal BonePressureTomography, X-Ray ComputedSyncopeBaroreflexDizzinessSyncope, VasovagalHemodynamicsExpiratory Reserve VolumeCardiac OutputTidal VolumeCraniocerebral TraumaLegSudden Infant DeathPulmonary Gas ExchangeReference ValuesFluid ShiftsTime FactorsPalate, SoftTechnetium Tc 99m Aggregated AlbuminCranial SuturesLung Volume MeasurementsEsophagusEsophageal pH MonitoringPulmonary CirculationNeckSperm HeadRestRibsOxygenMagnetic Resonance ImagingSleepHead Injuries, ClosedPharynxThoracic WallSleep ParalysisOccipital BoneBlood Flow VelocityFunctional Residual CapacityCraniosynostosesMolecular Sequence DataInhalationBedsDiaphragmLungPelvisAutonomic Nervous System DiseasesCarbon DioxideAirway ResistanceVentilators, Negative-PressureSpineRegional Blood FlowPlethysmographyCentral Venous PressureCephalometryReproducibility of ResultsImaging, Three-DimensionalBiomechanical PhenomenaProspective StudiesAirway ObstructionPneumoperitoneum, ArtificialTongueLymphatic IrradiationElectrocardiographyEsophageal Motility DisordersVenous PressureVeinsPulmonary VentilationRespiratory MusclesJugular VeinsFemur Head NecrosisTotal Lung Capacity