分娩镇痛进展课件

分娩镇痛进展课件1847年苏格兰产科医生SimpsonJ给分娩产妇吸入乙醚以缓解疼痛，得出的印象是药物可以缓解分娩痛，但同时要关注其副作用，包括对子宫收缩、腹部肌张力以及对胎儿的影响Epiduralanalgesiainlabourisusedbyabout100

000womeninBritaineachyearBMJ2002;325:357分娩痛产生的机制理想的分娩镇痛dramaticallyreducethepainoflabour,whileallowingtheparturienttoactivelyparticipateinthebirthingexperience.Inaddition,itshouldhaveminimaleffectonthefetusortheprogressoflabourRegionalanalgesiaforlabour

spinalopiatesandcombinedspinal-epidural(CSE)analgesiapatientcontrolledepiduralanalgesiacontinuousspinalanalgesianeuraxialblockade(epidural,spinal,CSE,continuousspinal)providesthemosteffectiveandleastdepressantanalgesiaEpiduralanalgesiaviaacathetertechniqueprovidesexcellentpainreliefandtheabilitytoextendthedurationoftheblocktomatchthedurationoflabour,butitisnot"instant"inonsetandmaybeassociatedwithmotorblock.One-shotspinalanalgesiausingalipidsolubleopioidisrapidandsimple,butisassociatedwithalimiteddurationofactionThecombinationofepiduralandspinalanesthesiaintoonetechnique,termed"CSE"providestheadvantagesofaspinal(speedofonset,lackofmotorblock)withtheadditionalflexibilityofrenewalwithanepiduralcatheter.CSEcanbesafelyusedtoprovidelabouranalgesiainparturientswhoaretoreceiveanepiduralforlabourspecificpatientswhowillgreatlybenefitfromthistechnique.Theseincludepatientsinearlyorlatelabour

earlylabourcanbemadecomfortablewithspinalnarcotics(suchassufentanilorfentanyl)whichwilllastforapproximatelytwotothreehours,duringwhichtimethepatientwillnothaveamotorblockandwillbeabletoambulate.advantageofCSEforpatientsinlatelabouristhealmostimmediatepainreliefCSEallowsforambulationoftheparturient,ithasbeencalledthe"walkingepidural."ArecentstudyhasevaluatedCSEand"mobileepidurals"andhasconcludedthatCSEprovidesbetterpainreliefintheearlystagesafterinsertionAnesthesiology2002;97:1567–75CSEanalgesiaforlabourisusuallyachievedusingashort-actinglipidsolublenarcoticsuchasfentanylorsufentanilmorphinehasbeendescribedasanintrathecalopiateforlabour,ithasseveraldisadvantagesincludingslowonset,incompleteanalgesia,prolongednauseaandpruritus,anddelayedrespiratorydepressionpruritusisassociatedwithlipidsolubleopioids,itisusuallymildandshortlivedanddoesnotgenerallyneedtobetreatedAreviewofthecomplicationsassociatedwithCSEhasconcludedthatCSEisassafeatechniqueasaconventionalepiduraltechniqueandisassociatedwithgreaterpatientsatisfactionNorrisMCetal.AnesthAnalg1995;79:529–37opioidsaremostoftenusedtoproduceanalgesiainthelabouringpatient:sufentanil2.5to10µg;

fentanyl10to25µg.

Incaseswherethesecondstageoflabourisimminent,thesubarachnoidadministrationofacombinationoflocalanestheticplusopioidshouldbeconsideredcombinationofsufentanil2.5to5µgplusbupivacaine2.5mgprovidesrapidanalgesiawithoutmotorblock,alleviatesthepainofthesecondstageoflabour,andlastslongerthansufentanilalone.AnesthAnalg1995;81:305–9EffectsofEpiduralAnalgesiaonLaborandMaternalandInfantOutcomes

AmJObstetGynecol2002;186(Suppl5):S31-68.AmJObstetGynecol2002;186(Suppl5):S69-77.TABLE1

EffectsofEpiduralAnalgesiaonLaborandMaternalandInfantOutcomes

Laborfactors

Outcome*

Pvalue

EffectsonlaborDurationoffirststage14Increasedby26minutesNS†Durationofsecondstage14Increasedby15minutes<.05

Painscore(100mmVAS)14

Firststage40mmlower<.0001Secondstage29mmlower<.001Useofoxytocin(Pitocin)afteranalgesia14Increased(OR,2.8;95%CI,1.89to4.16)<.05Third-orfourth-degreeperineallaceration13Increased(OR,1.7-2.7)N/AInstrument-assisteddelivery14Increased(OR,2.1;95%CI,1.48to2.93)<.05Cesareandelivery14OR,1.0;95%CI,0.77to1.28NS‡MaternaloutcomesFever>38°C(100.4°F)14Increased(OR,5.6;95%CI,4.0to7.8)<.001Lowbackache14

At3monthsOR,1.0;95%CI,0.6to1.6NSAt12monthsOR,1.4;95%CI,0.9to2.3NSUrinaryincontinence14NoincreaseNS§Breastfeedingsuccessat6weeks14NodifferenceNS§Infantoutcomes5-minuteApgarscore<7Nodifference13,14NSLowumbilicalcordpHNodifference13,14NSNeonatalsepsisevaluation13IncreasedN/ANeonatalantibiotictreatment13IncreasedN/APossiblecomplicationsandsideeffectsofintrathecalopioidsforlabourCSEhasbeenreportedtobeassafeasconventionalepiduraltechniquespruritus;

nausea/vomiting;

hypotension;

urinaryretention;

uterinehyperstimulationandfetalbradycardia;

maternalrespiratorydepression.

Uterinehyperstimulation/fetalbradycardiaspinalopioids,perhapsduetotheirassociateddecreaseinmaternalcatecholamines,mayprecipitateuterinehypertonicityandfetalbradycardiaPostduralpunctureheadache(PDPH)useofsmallbore"atraumatic"spinalneedleswillreducetheincidenceofPDPHinpatientsreceivingCSEtoapproximately1%orless.incidenceofunintentionalduralpunctureislessinCSEpatientsthaninpatientsreceivingconventionalepiduralspossibleexplanationforthisfindingisthat,aspartoftheCSEtechnique,thespinalneedlemaybeusedforverificationofcorrectplacementoftheepiduralneedlewhenthereisinconclusivelossofresistance.Subarachnoidmigrationoftheepiduralcatheteralmostimpossibletopassanepiduralcatheterthroughasingleduralholemadebya25gspinalneedleSpecialepiduralneedleswithaseparateportforthespinalneedlearenowavailableandshouldtotallypreventtheunintentionalsubarachnoidthreadingoftheepiduralcatheterRegardlessofneedleused,allepiduraldosesshouldbeincremental.RespiratorydepressionSufentanilandfentanyl-inducedcentralrespiratorydepressionhavebeenreportedbutareextremelyrareThisrespiratorydepressionoccursacutelyandthereforeanypatientreceivingCSEmustbeappropriatelymonitoredforsignsofrespiratorydepressionforaperiodofatleast20minfollowingadministrationofthesubarachnoidopioid.Anesthesiology1994;81:511–2

硬膜外阻滞应用的时机多数研究显示，过早采用硬膜外阻滞可以增加剖宫产率和器械助产的机率。美国妇产科医师协会推荐：如果情况允许，应该等宫口开至4～5cm再采用硬膜外阻滞行分娩镇痛，其他的镇痛措施也应该在这一时机应用，目的是减少剖宫产及器械助产率这一观点也在改变TimingofEpiduralAnalgesiaduringLabor

Mostobservationalstudiesshowhigherratesofcesareandeliverywithearlyadministrationofepiduralanalgesiathreerandomizedstudiesspecificallycomparingtheinitiationofepiduralanalgesiaatdifferentdegreesofcervicaldilatationinnulliparous(初产妇)womenfoundnodifferenceintherateofcesareandeliveryorinstrument-assistedvaginaldeliverybetweenwomeninwhomanalgesiawasinitiatedearlyandthoseinwhomitwasinitiatedlateEffectofEpiduralAnalgesiaonMaternalTemperatureandtheNewborn

Epiduralanesthesiainnonobstetricalpatientsisgenerallyassociatedwithadecreaseinbodytemperature.Epiduralanesthesiacausesvasodilatationintheanesthetizeddermatomes,whichleadstoaredistributionofheatfromthecoretotheperiphery,resultinginanetdecreaseinbodytemperatureIncontrast,observationalandrandomizedstudiesdemonstratethatepiduralanalgesiaduringlaborisoftenassociatedwithanincreaseinmaternalbodytemperaturetoover100.4°F(38.0°C)arandomizedtrialinwhichfeverwasreported,anadditional11percentofwomenreceivingepiduralanalgesiabecamefebrileduringlabor(15percent,vs.4percentofwomenwhoreceivednoepiduralanalgesia),andtheproportionofthepopulationaffectedwasevengreateramongnulliparouswomen(24percentvs.5percent)Manyinvestigatorsbelievetheassociationofepiduralanalgesiawithfeverisprobablyattributabletononinfectiouscauses,suchasanalterationintheproductionanddissipationofheatresultingfromepiduralanalgesiaFastingduringLaborandDelivery

recentdatafromtheUnitedStatesindicatethatforevery10millionbirths,sevenwomendiefromaspiration.AdvancesinanalgesiapermittheliberalizationofrequirementsforfastingduringlaborAnesthesiology1997;86:277-284

practiceguidelinesoftheAmericanSocietyofAnesthesiologistsrecommendlimitedamountsofclearfluidduringlaborrecentstudydemonstratingthattheuseofisotonicsportdrinksduringlaborhasthepotentialtodecreasetheriskofmaternalketosisassociatedwithstarvingwithoutincreasinggastricvolumeortheriskofnauseaandvomitingAnesthAnalg2002;94:404-408其他方法人工辅助(Continuouslaborsupportprovidedbyadoula)温水浴法注射无菌水：体位、按摩Intradermalinjectionsof0.1mLofsterilewaterinthetreatmentofwomenwithbackpainduringlabor.Sterilewaterisinjectedintofourlocationsonthelowerback,twoovereachposteriorsuperioriliacspine(PSIS)andtwo3cmbelowand1cmmedialtothePSIS.Theinjectionsshouldraiseablebbelowtheskin.Simultaneousinjectionsadministeredbytwoclinicianswilldecreasethepainoftheinjections.OtheradvancesinlabouranalgesiaContinuousinfusionofdilutelocalanestheticplusopioidroutineuseofcontinuousinfusionofdilutelocalanestheticspluslipidsolubleopioidsbycontinuousinfusionprovidedbetterpainreliefwhileproducinglessmotorblockdrugconcentrationshavebeentestedandcontinuousinfusionshavebeendemonstratedtobesafeforbothmotherandneona