PropofolAnesthetics, IntravenousHypnotics and SedativesManipulation, SpinalConscious SedationAnesthetics, CombinedAnesthesia Recovery PeriodThiopentalAnesthetics, InhalationMethyl EthersAnesthesia, GeneralAlfentanilDeep SedationManipulation, OrthopedicMonitoring, IntraoperativeMidazolamEtomidateMethohexitalFentanylElectroencephalographyConsciousness MonitorsAnesthetics, GeneralAnesthesiaAnestheticsIsofluraneManipulation, ChiropracticDose-Response Relationship, DrugNitrous OxidePiperidinesConsciousnessInfusions, IntravenousKetamineAnesthetics, DissociativeUnconsciousnessAdjuvants, AnesthesiaEmulsionsInfusion PumpsAmbulatory Surgical ProceduresPreanesthetic MedicationIntubation, IntratrachealAnesthesia, Inhalation