上海交大医学院仁济临床医学院五年制、七年制外科学（麻醉，局部麻醉部分）理论教案陈杰、蒋茹
掌握：局部麻醉的概念、局部麻醉分类、常用局部麻醉药药理特性。熟悉：影响局部麻醉药药理特性机理，局部麻醉药中毒的临床表现、防治措施。了解：各种局部麻醉要点。重点：局部麻醉并发症防治难点：局部麻醉药药理特性。教学内容：一、定义：LocalAnesthesia：Localanestheticdrugsactbyproducingareversibleblocktothetransmissionofperipheralnerveimpulses.用局部麻醉药（简称局麻药）暂时阻断某些周围神经的冲动传导，使受这些神经支配的相应区域产生麻醉作用，称局部麻醉（广义）。狭义的局部麻醉（简称局麻）不包括椎管内麻醉。二、局部麻醉药药理（一）结构：
Allthelocalanestheticdrugshaveathree-partstructure----aromaticgroup,amineandanintermediatechainbondatthecenter.Therearetwotypesoftheintermediatechain:esterandamide.Esteragentsincludeprocaine,chloroprocaineandtetracaine.Amideagentsincludelidocaine,bupivacaineandropivacaine.（二）AnesthesiaPerformance麻醉性能1、Dissociationconstant离解常数（pKa）pKa愈大，离子部分愈多，愈不易透过神经鞘和膜，起效时间较长，弥散性能愈差。普鲁卡因：9.0丁卡因：8.5利多卡因：7.9布比卡因：8.12、酯溶性：酯溶性愈高，效能愈强布比卡因、丁卡因>利多卡因>普鲁卡因3、蛋白结合：蛋白结合率愈高，作用时间愈长布比卡因：95.6丁卡因：75.6利多卡因：64.3普鲁卡因：5.8（三）常用局麻药的药代动力学特点1.吸收影响因素：给药途径、药物剂量与浓度、局麻药性能、血管收缩药等。2.分布：肺，心、脑、肾等；肌肉、脂肪和皮肤等3.生物转化和清除脂类：血浆脂酶酰胺类：肝细胞内质网微粒体酶水解
（四）Side-effectsoflocalanestheticdrugs1.Toxicity（毒性反应）Hypersusceptibility（高敏反应）1）.CausesA．Absoluteoverdosage（过量）B．Inadvertentintravascularinjection（误注）C．Thesitesofinjectionhavehighbloodsupplyandtheanestheticsolutionhasnoadrenaline（吸收快）D．Thetolerabilityofthepatientsdecreased（耐受差）2）.TheclinicfeaturesofToxicity中毒临床表现ANumbnessortinglingoftongueandcircumoralarea（麻木、舌麻、口周麻）BAnxious,drowsy,tinnitus（焦虑、昏睡、耳鸣）CConsciousnessislost（神志消失）DConvulsion（惊厥）EComaandapnea（昏迷、呼吸停止）FCardiovascularcollapse（心血管虚脱）3）.Theclinicalfeaturesofallergicreaction过敏反应表现AUrticaria寻麻疹Blarynxedema咽喉水肿3）Constrictionofbronchioles支气管痉挛CHypotension低血压DSwelling血管神经性水肿EAnaphylacticshock过敏性休克4）.Preventionandtreatmentoftoxicity中毒防治A用酰胺类药物可减少过敏反应的发生BAdrenaline（肾上腺素）CGlucocorticoid（肾上腺糖皮质激素）DAntihistamine（抗组胺药物）三常用局麻药Procaine普鲁卡因Lidocaine利多卡因Tetracaine丁卡因Bupivacaine布比卡因Ropivacaine罗哌卡因（一）Procaine普鲁卡因Procaineisalowpotentandshortdurationanestheticagent.Becauseoflowtoxicity,itiscommonlyusedforlocalinfiltrationanesthesia.Theincidenceofallergicproblems,shortshelf-lifeandbriefdurationofactionofprocainehaveresultedinitsinfrequentuseatthepresenttime.（二）Tetracaine丁卡因Tetracaineisacommonlyused?drugofhightoxicity.Itisalsoverypotentandisthestandarddrugfortopicalanesthesiaandnerveblock.Ithasaprolongeddurationofaction,butalsoaslowonsettime（三）Lidocaine利多卡因Havingbeenusedsafelyandeffectivelyforeverypossibletypeoflocalanestheticprocedure,lidocaineiscurrentlythestandardagent.Itisalsoastandardantiarrhythymic.（四）Bupivacaine布比卡因Anumberofdeathshaveoccurredaftertheaccidentalintravenousadministrationoflargedosesofbupivacaine,andsomeconcernhasbeenexpressedthatthisdrugmighthaveamoretoxiceffectonthemyocardiumthanotherlocalanestheticagents.（五）Ropivacaine罗哌卡因Ropivacaineisslightlylesspotentthanbupivacaine,andproducesaslightlyshorterduration.Atequipotentconcentrations,ropivacaineappearstobelesslikelythanbupivacainecardiaccollapseandarrhythmias,andresuscitationismorelikelytobesuccessfulifcardiotoxicitydoesoccur.
四Localanesthetictechniques（局麻技术）（一）Topicalanesthesia表面麻醉1.Topicalanesthesiameansthelocalanestheticagentsarespreadonmucosaeorappliedonskin（e.g.Emla）toproduceanestheticeffect.2.Topicalanesthesiaisoftenusedfor?operationsoneye,nose,larynx,tracheal,andurethraorvenepunctureinchildren.3.Tetracaine1-2%andlidocaine2-4%（二）Localinfiltrationanesthesia局部浸润麻醉沿手术切口线分层注射局麻药，阻滞组织中的神经末梢，称为局部浸润麻醉。
局部浸润麻醉的注意事项注入组织内的药液要有一定容积,使局麻药在组织内形成张力,以便借水压作用能与神经末梢广泛接触,从而增强麻醉效果.避免穿刺针在组织内弯曲或折断。每次注药前都要回抽,以免药液误注入血管,或者边注药边推进穿刺针.局部感染或癌肿部位不宜注药。（三）Regionalanesthesia,Fieldblock（区域阻滞）在手术区的四周和底部注入局麻药,阻滞通入手术区的神经纤维,称为区域阻滞.
区域阻滞的优点可避免穿刺肿瘤组织;不会因局麻药浸润后,组织水肿使小的肿块不易扪及;不会使手术区的局部解剖因注药而难于辨认.（四）Intravenousregionalanesthesia（IVRA）（静脉局部麻醉）IVRAinvolvesisolatinganexsanguinatedlimbfromthegeneralcirculationbymeansofanarterialtourniquetandtheninjectinglocalanestheticsolutionintravenously.Analgesiarapidlyoccurandresultfromlocalanestheticactiononperipheralnerveendings.
ChoiceofdrugsforIVRA0.25%procaine100~150ml0.5%procaine60-80ml0.5%lidocaine40mlRelevantproblemsTourniquetpainSystemictoxicityInsufficientanalgesia（五）Nerveblock（神经阻滞）Nerveblockmeanstheinjectionofalocalanestheticoraneurolyticagentintoornearaperipheralnerve,asympatheticnerveplexus,oralocalpain-sensitivetriggerpoint.在神经干、神经丛或神经节的周围注射局麻药，阻滞其冲动传导，使受它支配的区域产生麻醉作用，称神经阻滞。
1.Cervicalplexusblock,颈丛神经阻滞颈神经由C1-4神经的前支组成，它们构成颈浅丛和颈深丛。浅丛分布于颌下和锁骨上整个颈部、枕部区域的皮肤和浅层组织。深丛分布于颈前及颈侧的深层组织。颈丛神经阻滞的适应症：颈部表浅短小外科手术。颈浅丛阻滞的方法颈深丛阻滞的方法
ComplicationsAtoxicreaction,Bthephrenicblockade,Ctherecurrentlaryngealnerveblockade,DHorner’ssyndrome,Ehematoma,Finadvertentepiduralinjection,Gtotalspinalblockade.
2.Brachialplexusblock臂丛神经阻滞臂丛由C5-8和T1的脊神经前支组成，至肌间沟被肌膜包裹形成鞘膜，在锁骨上方形成锁骨下动脉鞘膜，在腋窝形成腋鞘。阻滞臂丛神经一般就在肌间沟、锁骨上、锁骨下血管旁和腋窝进行。适应症：适用于上肢手术、肩关节手术和上肢关节复位术。
Techniquesforbrachialplexusblock
a.Interscalenebrachialplexusblock
b.Axillarybrachialplexusblock
c.Supraclavicularbrachialplexusblock
ComplicationsAtoxicreaction（毒性反应）Bthephrenicblockade（膈肌阻滞）Ctherecurrentlaryngealnerveblockade（喉返神经阻滞）DHorner’ssyndrome（霍纳氏综合症）Einadvertentepiduralandsubarachnoidinjection,andpneumothorax（意外硬膜外、蛛网膜下腔注射、气胸等）
3.Digitnervesblock指（趾）间神经阻滞
4.Intercostalnerveblock（肋间神经阻滞）方法见图
二、并发症：气胸、局麻药中毒等
Summary总结一、Definition定义二、Localanestheticpharmacology局麻药的药理特性三、CommonLocalanesthetictechniques常用局部麻醉技术Brachialplexus四、block&Cervicalplexusblock臂丛、颈丛神经阻滞要点思考题
局部麻醉的定义局部麻醉药中毒的心血管系统表现常用局部麻醉技术返回 ｜ 上一章 ｜ 下一章 ｜
