Anesthesia, RectalAnalgesics, OpioidPain, PostoperativeInfusions, IntralesionalAnalgesia, Patient-ControlledMorphineIntraoperative CareIntraoperative PeriodPain MeasurementReceptors, Opioid, muMonitoring, IntraoperativeReceptors, OpioidReceptors, Opioid, deltaReceptors, Opioid, kappaIntraoperative ComplicationsOpioid PeptidesNarcotic AntagonistsNaloxoneOpioid-Related DisordersNaltrexoneEnkephalinsEnkephalin, Ala(2)-MePhe(4)-Gly(5)-NarcoticsFrozen SectionsNeuronavigationPostoperative ComplicationsEnkephalin, D-Penicillamine (2,5)-EndorphinsDynorphinsBlood Loss, SurgicalTreatment OutcomeBuprenorphineIntraoperative AwarenessEnkephalin, LeucineSurgery, Computer-AssistedFentanylEnkephalin, Leucine-2-AlanineRetrospective StudiesPainNeurosurgical ProceduresDiprenorphineAnalgesicsAnesthesia, Generalbeta-EndorphinProspective StudiesIntraoperative Neurophysiological MonitoringBenzeneacetamidesDrug ToleranceMorphinansPreoperative CareAnalgesiaMethadoneParathyroidectomyLaparoscopyTime FactorsHydromorphoneBenzomorphansPostoperative CareAnesthesiaEchocardiography, TransesophagealPyrrolidinesReoperationSubstance Withdrawal SyndromePostoperative PeriodHeroinBlood Transfusion, AutologousFollow-Up StudiesNeurosurgerySurgical Procedures, Minimally InvasiveSentinel Lymph Node BiopsyOpiate Substitution TreatmentSurgical Procedures, OperativeDose-Response Relationship, DrugCholangiographyAlfentanilTomography, X-Ray ComputedPerioperative CareCardiopulmonary BypassIndocyanine GreenChronic PainPrescription Drug Misuse