Analgesia, EpiduralAnesthesia, EpiduralAnalgesiaBupivacainePain, PostoperativeAnalgesia, ObstetricalAnalgesics, OpioidFentanylAmidesPain MeasurementMorphineOrosomucoidLabor, ObstetricInfusions, IntravenousArthroplasty, Replacement, KneeDouble-Blind MethodInfusions, ParenteralInfusion PumpsAcupuncture AnalgesiaAnalgesicsMeperidineSufentanilPainInfusions, Intra-ArterialLabor PainNerve BlockInjections, SpinalAnesthesia, ObstetricalAnesthesia, SpinalTramadolAnalgesics, Non-NarcoticNaloxoneDose-Response Relationship, DrugCesarean SectionPostoperative Nausea and VomitingPain ThresholdDrug ToleranceAnesthesia, GeneralConscious SedationInterpleural AnalgesiaLidocaineDrug Administration ScheduleInfusion Pumps, ImplantableKetorolacInjections, IntravenousKetamineReceptors, Opioid, muHypnotics and SedativesHydromorphoneAlfentanilClonidinePregnancyLabor Stage, FirstPain ManagementTime FactorsFemoral NerveRats, Sprague-DawleyAnesthesia and AnalgesiaAnesthetics, CombinedPirinitramideProspective StudiesReceptors, OpioidNarcotic AntagonistsButorphanolAnesthesia, IntravenousInfusions, SubcutaneousDexmedetomidineNalbuphineBlood PressurePiperidinesInfusions, IntralesionalThoracotomyAnesthesia, ConductionAdjuvants, AnesthesiaTreatment OutcomePropofolMorphine DerivativesOpioid PeptidesMepivacaineNitrous OxideAnesthetics, IntravenousKetoprofenHemodynamicsPruritusElectroacupuncturePostoperative CareHyperalgesiaPlacebo EffectAnesthesia, LocalPain, IntractablePeriaqueductal GrayAnesthetics, DissociativeEpinephrineHysterectomyHeart RateDogsAmbulatory Surgical ProceduresBrachial PlexusPentazocineInjections, Intraventricular