AnalgesiaAnalgesia, EpiduralAnalgesia, ObstetricalAnalgesia, Patient-ControlledAnalgesics, OpioidPain, PostoperativeMorphinePain MeasurementBupivacaineAnesthetics, LocalFentanylAcupuncture AnalgesiaAnalgesicsAnesthesia, EpiduralMeperidineSufentanilLabor PainPainNerve BlockInjections, SpinalAnesthesia, ObstetricalLabor, ObstetricDouble-Blind MethodAnesthesia, SpinalAmidesTramadolAnalgesics, Non-NarcoticNaloxoneCesarean SectionPostoperative Nausea and VomitingInjections, IntravenousPain ThresholdInterpleural AnalgesiaAnesthesia, GeneralDrug ToleranceConscious SedationReceptors, Opioid, muKetorolacLidocaineLabor Stage, FirstHydromorphoneClonidineKetaminePain ManagementAnesthesia, CaudalPirinitramideAlfentanilFemoral NerveAnesthesia and AnalgesiaPregnancyHypnotics and SedativesReceptors, OpioidDose-Response Relationship, DrugAnesthetics, CombinedNarcotic AntagonistsButorphanolAnesthesia, ConductionNalbuphineDrug Administration ScheduleProspective StudiesThoracotomyMepivacaineOpioid PeptidesAdjuvants, AnesthesiaElectroacupunctureMorphine DerivativesPruritusKetoprofenNitrous OxideAnesthesia, IntravenousPlacebo EffectPiperidinesHyperalgesiaAnesthesia, LocalPostoperative CarePeriaqueductal GrayInfusion PumpsAmbulatory Surgical ProceduresDexmedetomidinePentazocineBrachial PlexusHysterectomyTime FactorsAnesthetics, DissociativeInfusions, ParenteralPain, IntractableInjections, EpiduralOxycodoneAcetaminophenPain PerceptionAnesthetics, IntravenousTreatment OutcomeNeostigminePropofolDeglutitionPrilocaineNociceptorsRats, Sprague-DawleyDelivery, ObstetricObstetric Labor Complications