Supine PositionSkullProne PositionPosturePatient PositioningSkull BaseHeadSkull NeoplasmsSkull Base NeoplasmsTilt-Table TestSkull FracturesHead-Down TiltGravitationHypotension, OrthostaticHeart RateHead and Neck NeoplasmsSupinationHead MovementsBlood PressureDizzinessNephrostomy, PercutaneousRespiratory MechanicsSyncopeSyncope, VasovagalAutonomic Nervous SystemBaroreflexMovementValsalva ManeuverHemodynamicsPressureRespirationLegCardiac OutputSkull Fracture, DepressedFacePulmonary Gas ExchangeIndoraminFemur HeadEsophagusTomography, X-Ray ComputedEsophageal pH MonitoringReference ValuesBiomechanical PhenomenaParietal BoneTime FactorsPalate, SoftTidal VolumeRotationRestRegional Blood FlowPulmonary CirculationOxygenBlood VolumeNeckExpiratory Reserve VolumeExercise TestBlood Flow VelocityMagnetic Resonance ImagingCraniocerebral TraumaSudden Infant DeathOrientationTongueFluid ShiftsSpineExerciseTechnetium Tc 99m Aggregated AlbuminPlethysmographyCranial SuturesLung Volume MeasurementsAutonomic Nervous System DiseasesVascular ResistanceReproducibility of ResultsCephalometrySperm HeadElectrocardiographyRibsVenous PressureSympathetic Nervous SystemPhysical ExertionLungOropharynxSleepHead Injuries, ClosedPharynxCarbon DioxideImaging, Three-DimensionalVeinsThoracic WallProspective StudiesSleep ParalysisOccipital BoneGastroesophageal RefluxFunctional Residual CapacityThoraxCraniosynostosesMolecular Sequence DataInhalationBedsDiaphragmAdaptation, Physiological