DexmedetomidineMedetomidineIntraoperative CareIntraoperative PeriodAdrenergic alpha-2 Receptor AgonistsAdrenergic alpha-AgonistsHypnotics and SedativesMonitoring, IntraoperativeIntraoperative ComplicationsImidazolesConscious SedationAdjuvants, AnesthesiaAnalgesics, Non-NarcoticReceptors, Adrenergic, alpha-2ShiveringMidazolamDeep SedationHemodynamicsClonidinePreanesthetic MedicationConsciousness MonitorsFentanylAdrenergic alpha-AntagonistsAirway ExtubationIdazoxanPropofolAnesthesia, GeneralImidazoline ReceptorsAdrenergic alpha-2 Receptor AntagonistsAlfentanilAnesthesia Recovery PeriodInfusions, IntravenousFrozen SectionsDioxanesPostoperative ComplicationsPsychomotor AgitationNeuronavigationDouble-Blind MethodDose-Response Relationship, DrugInjections, SpinalAnesthetics, IntravenousAdjuvants, PharmaceuticAnalgesicsAnesthesia, IntravenousBlood Loss, SurgicalTreatment OutcomeAnesthetics, InhalationPostoperative CareIntraoperative AwarenessAnalgesiaPremedicationSurgery, Computer-AssistedSympatholyticsAnestheticsHeart RateDeliriumIsofluraneProspective StudiesAnalgesics, OpioidLocus CoeruleusPain, PostoperativeAnesthetics, LocalRetrospective Studies