Supine PositionProne PositionPatient PositioningPostureTilt-Table TestHead-Down TiltHeart RateSupinationHypotension, OrthostaticNephrostomy, PercutaneousGravitationBlood PressureRespiratory MechanicsAutonomic Nervous SystemRespirationIndoraminValsalva ManeuverSyncopeBaroreflexPressureDizzinessMovementHemodynamicsSyncope, VasovagalExpiratory Reserve VolumeCardiac OutputTidal VolumeLegSudden Infant DeathPulmonary Gas ExchangeFluid ShiftsLung Volume MeasurementsPalate, SoftTechnetium Tc 99m Aggregated AlbuminEsophageal pH MonitoringEsophagusPulmonary CirculationReference ValuesHeadRestOxygenSleepTime FactorsThoracic WallSleep ParalysisFunctional Residual CapacityBlood Flow VelocityMolecular Sequence DataInhalationRibsDiaphragmLungAutonomic Nervous System DiseasesPharynxBedsCarbon DioxideAirway ResistanceVentilators, Negative-PressurePlethysmographyCentral Venous PressureElectrocardiographyPneumoperitoneum, ArtificialRegional Blood FlowLymphatic IrradiationEsophageal Motility DisordersPelvisVenous PressureAirway ObstructionVeinsTonguePulmonary VentilationRespiratory MusclesTotal Lung CapacityBlood VolumeSleep Apnea, ObstructiveProspective StudiesSpineVascular ResistanceAnesthesia, SpinalRespiration, ArtificialIntraocular PressurePolysomnographyTonometry, OcularOropharynxNeckJugular VeinsAmino Acid SequenceExercise TestBlood Gas AnalysisReproducibility of ResultsRespiratory Distress Syndrome, AdultExerciseSnoringSphygmomanometersBase SequenceThoraxRespiratory Function TestsTomography, X-Ray ComputedSympathetic Nervous SystemSignal Processing, Computer-Assisted