AnalgesiaAnalgesia, EpiduralAnalgesia, ObstetricalAnalgesia, Patient-ControlledAnalgesics, OpioidPain, PostoperativeMorphinePain MeasurementBupivacaineAnesthetics, LocalAcupuncture AnalgesiaFentanylAnalgesicsAnesthesia, EpiduralMeperidineLabor PainSufentanilPainNerve BlockInjections, SpinalLabor, ObstetricAnesthesia, ObstetricalAmidesAnesthesia, SpinalTramadolDouble-Blind MethodAnalgesics, Non-NarcoticNaloxoneCesarean SectionPostoperative Nausea and VomitingPain ThresholdInterpleural AnalgesiaDrug ToleranceReceptors, Opioid, muAnesthesia, GeneralConscious SedationKetorolacLabor Stage, FirstHydromorphoneLidocainePain ManagementAnesthesia, CaudalClonidineAnesthesia and AnalgesiaKetamineFemoral NerveReceptors, OpioidPregnancyPirinitramideHypnotics and SedativesButorphanolAlfentanilNalbuphineNarcotic AntagonistsAnesthetics, CombinedAnesthesia, ConductionThoracotomyOpioid PeptidesElectroacupunctureMepivacainePruritusKetoprofenAdjuvants, AnesthesiaPlacebo EffectMorphine DerivativesHyperalgesiaProspective StudiesAnesthesia, LocalPeriaqueductal GrayNitrous OxidePentazocinePostoperative CareDexmedetomidineAmbulatory Surgical ProceduresHysterectomyPiperidinesDose-Response Relationship, DrugBrachial PlexusPain, IntractableOxycodonePain PerceptionInjections, EpiduralAcetaminophenAnesthesia, IntravenousAnesthetics, DissociativePrilocaineNociceptorsDelivery, ObstetricObstetric Labor ComplicationsNeostigmineNociceptive PainInjections, IntravenousExtraction, ObstetricalDipyroneAnti-Inflammatory Agents, Non-SteroidalSpinal CordDrug Administration ScheduleSubarachnoid SpaceNarcoticsInjections, Intra-Articular