Prone PositionSupine PositionPatient PositioningAbdomenAbdomen, AcuteNephrostomy, PercutaneousRespiratory Distress Syndrome, AdultPosturePulmonary Gas ExchangeSudden Infant DeathDisposable EquipmentRespiratory MechanicsPositive-Pressure RespirationRespiration, ArtificialNitrogen RadioisotopesVentilation-Perfusion RatioLaryngopharyngeal RefluxPronationPulmonary CirculationBedsSpineEquipment ReuseTomography, X-Ray ComputedUreteral CalculiOrgans at RiskLaryngeal MasksAirway ManagementPulmonary VentilationIntraoperative ComplicationsPressure UlcerBlood Gas AnalysisSleepGravitationIntubation, IntratrachealIntraoperative CareRadiography, Abdominal