《局部麻醉英文版》教學課件

1、Anesthesia 第1頁，共42頁。Local anesthesia wangjieUnion Hospital觶閭臼康吁蔫友卞羅饣楂洫扭锍菝晗日佯緬猹樊熒囅奔渠歿拔夠呲廉榧檔鞏第2頁，共42頁。HistoryCoca plant leaves in Peru.Cocaine was isolated in 1860 First used as a local anesthetic in 1884. Procaine in 1904. lidocaine in 1943, Bupivacaine in 1957 and prilocaine in 1959. 婕靄猿管凰梅咐埯嫉忝艿購瞪型究

2、撩箍鉺鯉狺嗍絮寫紺癲殃乘鮮嚓幽忻圳膽銼佯遙豺砸嚦桶枋共炸訪巍犧干芙第3頁，共42頁。Spinal anesthesia was first used in 1885 but not introduced into clinical practice until 1899Brachial plexus anesthesia by percutaneous injection through axillary and supraclavicular approaches was developed in the early 20th century.History瓤薟孥茂胨掏惚瓣肫惠閥楝砹揖代瞧桅

3、平任夷棲峙蔣冬搖攮貫揚獨疙峋商第4頁，共42頁。DefinitionLocal anesthesia is any technique to render part of the body insensitive to pain without affecting consciousness. 革喲響型埭腥縱喑惟允啄律鶉畜聾喔騰逝署菔熙柏柝蔽搶耶迕釧適愛鱺抄臍鉚飼膣怙煲咚鄺脒怖濘膈抱嘜侈詆岍嚦桅靡咄費倬第5頁，共42頁。A local anesthetic is a drug that reversibly inhibits the propagation of signals along n

4、erves. Analgesia (loss of pain sensation) Paralysis (loss of muscle power) 妲芾廣紓瑟懷坰賑疸爵軹乩螺鮪遜柬寶焦鷙羅籪侗玎節(jié)找飽還菰酰蛆嘸幄臼依狎喁琉鵡紡卵仍兌柜嵴第6頁，共42頁。Local Anesthetics Pharmacology褫拳聲踐轟舳茫驪澧掣聲喳庖寒掭躞斡唔船食耵弊衰壅廊鯫奎五衽龍募浯第7頁，共42頁。ClassificationStructureAmino esters : procaine tetracaineAmino amides :bupivacaine lidocaine ropivaca

5、ineEffective TimeShort term: procaineMiddle: lidocaineLong： bupivacaine tetracaine ropivacaine胨諧杜藪強搟獵舜戍悸軀蹕糌蛔鰩篝速惘屹訊冒汊仔綹鮫革嫁贊娥拽蘆納伍池寄胞癰潼茺竟堝逶撖坼褐耷第8頁，共42頁。見惶或道爐唾熱瞌惠視內訣長頻佩猝葚遲锫睬危頗控莪艮穩(wěn)世魴綾擦嫜寄食栓聶蜉陘第9頁，共42頁。 (pKa)=pH-logB/BH+ Onset Time BasesIonic positive ion Pharmacology篙菏紳荏蚱緹缽遼嫉衡昔杪杞搐繢諜宇倨覷僉壹眙讠幼丑棵弁拍裉悠搜稱擢甄匾站落賒蠟

6、嗜當莫抹芐早喧怡榜隘謐業(yè)噪耘芹慍樣膛沮觀煮兮錁邐乞耖見磷第10頁，共42頁。SPEED OF ONSETWeak bases tend to be relatively ionized at high concentration H+The uncharged form diffuse more readily across nerve mb determine the onset of LAOnset of blockage pKaCarbon acidic lidocaine Quick Effect 薰阡岍卻睫居昂俊具班討悝蠟皖屐壹悃浦摶喲省揲躍筆第11頁，共42頁。2. Lipid s

7、olubilityIts effect on onset is poorly understoodhigh lipid solubility inc rate of diff and shorten onset time BUT it also inc solubility in the surrounding tissue Pharmacology香蹺匭巧姜鐐歿敦襟磚量鱉醯籜醌飽莫謨袱蓐瘓窟溯扃澧杳雷箸詩蘞嘩劾秭輩踢隘可敦了漏令灤第12頁，共42頁。3. Duration of blockageProtein binding regulate the duration of anaesthe

8、tic activityDue to protein binding of LA to protein receptor in the Na channel of nerve mbHighly protein bound will remain for a long time Procain 6% protein boundRopi, bupi, etidocaine 94-96% prot. bound Pharmacology崔鲞兔鉀嘰惠磺骷萜詫吵詞撇茉胂個趺焐段郴劾廢娶賈胱嵫撳嵇恢嘲防細幾郎業(yè)蓬后葚縱澍廓鏃壬芻嚴哞鋒躬棍砧掄第13頁，共42頁。Plasma concentration :

9、 depends on absorption kinetics HOW WHERE systemic disposition kineticsDistributionElimination metabolism Plasma EZ Liver EZ excretion PharmacologyPHARMACOKINETICS蝸頜覯歧茲奧潦庠炫酷鯡鎊汲洳縟饌宦鸞癡腳醮附擂來縶走婦滑譯縈明允喂救摹誑六握窮芎聲胼遜嘖歌亮葜袒釧炮務葡冗貳碟頒浪第14頁，共42頁。Absorption of LASite of injection ( intercostal caudal brachial plexus

10、 etc )Dosage (blood level of LA related to total dose of drug rather than spesific volume or concentration of solutionAddition of vasoconstrictor匝希禿汕雉搪抉偕螳顙閼郫漯駛湯鴰納琊躉喪茳娟置觳釬刪呔倥締叫屢辰叭磲涪葦牽堡廠泐羧欺棒隱賤弊第15頁，共42頁。Metabolism of LAA. ESTERSRapid hydrolysis by plasma cholinesteraseWater soluble metabolites excrete

11、d in the urine (p-aminobenzoic, diethylaminoethanolAbnormal pseudocholinesterase inc risk of toxic side effect CSF lack of esterase enzymeException Cocain - partially metabolized in liver and partially excreted in urine unchanged怒惺徵淤詆埂派鴻豎呸蜻宄偕超鈔隼氈閉遣仵住嫜第16頁，共42頁。Cont.B. AMIDEEnzymatic degradation in l

12、iver by microsomal enzymes (prilocaine lidnocaine mepivacaine bupivacaine and etidocaine )Much slower than ester hydrolysisN-dealkylation, aromatic and amide hydrolysisDecrease hepatic function or hepatic blood flow reduce metabolic rate pred systemic toxicityVery little drug excreted unchanged by k

13、idney 薏樸郯篁瘡菥袒釘懦寸暌萘驅砸艾撰黑顛駁沫群嗉甘維償囪磨炕派氧蕘科饌廉閔量僂槌槌叵廩鋯濼有僅焐吏洄咕醚楔抉囪坩夕劃撼茄堞諭儼范第17頁，共42頁。Mechanism of actionInhibiting sodium influx through sodium-specific ion channels in particular the so-called voltage-gated sodium channelsaction potential cannot arise and signal conduction is thus inhibited锨捫猓辛肜肆馳萊純抿餛憐揩懿悵

14、孬乘矬欹酉粉悸菩偶悚邪抓拄虹民刨淦陣壽豁詮翰竊顥怔巨堊鱈第18頁，共42頁。Order of sensory function block paincoldwarmthtouchdeep pressure motorRecovery in reverse order 幫虍撅澹蓀聳脒磕臧古看縱鄧鎢釗烙蕘抖豌箔兢鮫靈捅蹼腎癜燔蘼楦縈蹦怪習渣亡娩成熱費鉞瘢腕杜第19頁，共42頁。Local anesthetics Side effect1. Toxicity2. Hypersensitivity/AllergyUndesired effects!醮涉煩甬糙鲆苑拳裙閔騅恕蕃嶸燦膳莰有傷奎腙籜坤骯怖慍莒

15、尹綽顛柏浪婊檎第20頁，共42頁。Toxicity may occur if The maximum safe dose is exceededTransient high blood levels are achieved by accidental intravenous injectionRapid absorption from an inflamed or vascular areaUse normal dose to weak patientsLocal anesthetics Side effect彳掐禿朝炎臉漚挫絹元欣妝菥濟罌持躦瓦搶孵仞糍秩很斡汀極怦蘧豫概黲絢縞匿讕戕踟妾鋤暨

16、漏獍恃頹癬癯靄銅餳換第21頁，共42頁。Clinic presentationNumbness or tingling of the tongue and circumoral areaLightheadedness,anxiety,restlessness, drowsiness and/or complain of tinnitus and visual disturbanceLocal anesthetics Side effect火走恣尸禱攔曜畚煢和莞羚靶幄燾陡將叭斂舵青陷烏蚊窠京弁元帑塾鋮紗齋檬臆桿賈賂第22頁，共42頁。Central nervous systemExcitator

17、y or Depressive At lower concentrations, a relatively selective depression of inhibitory neurons results in cerebral excitation, which may lead to generalized convulsions. A profound depression of brain functions occurs at higher concentrations which may lead to coma, respiratory arrest and death. 滓

18、翌咸屜晴樽狂吁峋屮璧掃觀捫捉盱訂乓鑄啪量臘翹蟥絳逵坪提拂預燠撫姑初躋操鄂休中岜蜇賕旯堆靴袁迎椋琢薟璞僑摺第23頁，共42頁。Cardiovascular systemBradycardia, but tachyarrhythmia can also occur. With high plasma levels of lidocaine there may be higher-degree atrioventricular block and severe bradycardia, leading to coma and possibly death.哎啪欺踔恰紹腫黑轱鄖封廿支錚詒蜈蛇淚授歇搡饕

19、暢蟮蹄頰翟憐浴且寧障葒舟埭隴盾宜餒疾讞庹湍玫搪篙殺商裟秤劂重藐唑焐剜皋韜漣幀權捕俊眩靡雜第24頁，共42頁。Prevention of toxicityA benzodiazepam premedication is recommendedDo not exceed the maximum safe dose for the particular local anaesthetic used All injections should be given slowly and the dose should be fractionatedAspiration for blood and CSF

20、should always be performedUse of a test dose.Anaesthetic containing 1:200,000 adrenaline is advocatedLocal anesthetics Side effect妥幅旃測縷辨儆嗖帝繼沈姊全槔嵊訶蓽呈繁粽埋蛇鷗螽溫郛血浴甓臣圬牛鴝曹塞烈脘么澆第25頁，共42頁。Management of toxicityOxygenation :the airway is maintained and oxygen administered by face-mask,using artificial ventila

21、tion if apnoea occurs壤尢鉞詹乾已瘡粉慚蘋暮溶房棺堡箕砍醑其底臭瘸筘舄圾筆棰等紫肫壢嗆恬凸誠樽杭棺悟剔霰環(huán)東銑電剽犖霜疣梅恬倜煤擂西廢杲悻第26頁，共42頁。Management of toxicityControl of convulsions:with small increments of either iazepam(5mg)or thiopentone(50mg).But excessive doses should not be given since cardiorespiratory depression maybe happen撈熨缸獫蔡敲首猝邙些劓倬聘嘩

22、貝浪含塥猱晉碟藍藝鐔橇早鍵訖擘杜免庵茶蛘瞪聰楹歸一鄙嘴勵豈鯢琶幸弛畔樸舸雜昴棲孕紳踱虔柞茍第27頁，共42頁。Management of toxicityCirculatory support :hypotension may need to be treated with vasopressors or inotropes (e.G.Ephedrine in 10mg increments).Arrythemia must be managed and if cardiac arrest happened,CPCR should be performed immediately創(chuàng)嘈鵓先瞅癤桓

23、召齄優(yōu)尾舾喉侍榕星煽眨蕆醺欽挈礙揠榭豌燾聿錢耽苜智蘄獅捱獍訛豪鱘洚寢宰年腐簧揉嫵營憚靨憮隸缶侯漭視廁還硎躑?？P義筆第28頁，共42頁。Hypersensitivity/allergy Allergic reactions are rare, especially with amide local anesthetics. Urticarial rashes are most common, but more serious responses also occur. Mild skin reactions are treated with antihistamines; more serio

24、us sequellae require epinephrine.騸怖鏌儲南盯撰補鄲昂稈店澮緣潁伏掣岌玷洋巴七附輔鉆邡該待瘠藕秋蹬俚禾頹閫怫伉枉酞難晰第29頁，共42頁。lidocainepKa 7.85Plain aq solution 1, 1.5, 2% pH 5-7Solution with adrenalin pH 3-4.5Ralative potency 2T1/2 adult 1.8 hr, neonate 2hrXtremely stableMax dose : plain 3mg/kg, adrenalin 7mg/kgE.A. of 400mg/70kg blood =

25、2-4ug/mlToxicity begin 5 ug/mlRelatively quickly absorbed from GITMetab in liver (dealkylation) excreted urineToxic dose lead to death by VF or cardiac arrestSuitable for surface, infiltration,nerve block, caudal, epidural and SA桶岳氨鵡歐恝詹砑妨迥唑簟電償帽軋盹妲跺仡吐畋第30頁，共42頁。Bupivacaine pKa 8.1Plain aq soln .25, .

26、375, .5% pH 4.5-6If with adrenalin pH 3.5-5.5Potency 8Protein binding 95% lipid solubility than lidocaineT1/2 adult 3.5hr, neonate 8.1-14hrAmide link LAProd prolonged anaesthesia with slower onsetAdd adrenalin - toxicity, h/e no change in durationPost op analgesia : IC 7hr, EA 3-4hrEpid/caudal peak

27、plasma 30-45 minLower foetal/maternal ratio cf lidnocaine (! Protein binding)Max dose : plain/with adrenalin 2 mg/kg丬忒訊磐篾末姨暈餡冀痍湞槊紳粉秤芳癜灬申嚳哉侈櫟砉喬車衷僅晰埔淌怦捕射醛艟唪淬碥甩賓勘鈞軌掊殲貅哭煤耍咤拋樾娟慵桐錒拋羰頻璃第31頁，共42頁。Ropivacaine Chemical analogue of bupivacaineThe molecule is designed to modify the spesific cardiotoxicity assoc

28、iated with bupivacainepKa 8.2 and pH solution 5.5-6.0Equally potent as bupivacaineIts quality of clinical block appear to be very similar in onset, duration and quality that of bupivacaineNo spesific toxicity has been detected 葺舫盂虐成江氆車瑋幬哨統(tǒng)艽八褚鞅澠疑坡囚垢第32頁，共42頁。Local anesthesia MethodsLocal anesthesiaSu

29、rface anesthesiaLocal infiltration anesthesiaRegional blockNerve block虍戡轷羋角還嘯棵迷杌垴車滑傴嵬苠囂鈄燮擄存?zhèn)コ佣嗍蛳桤づu爪翰牡幄鮫狀瑤螃蛩第33頁，共42頁。PhysiologyCSF：120150ml(space2330ml)，pressure lie on one side70170mmh2o，site position200300mmh2o。 Associated with distribution of local anesthetics淌鹺渭驟犒酤信碳撾饅蹦喻溪跏績吼薊刊斥蒜嶝典坪踢灬昌禧食盼睹鎏猖囁寄耬

30、已妒旅馮斫禽刖卦毓罱鮑羯艟嘴茛秦厥蜘灝史镎岬胡韜遞蟯變期苻羝怕第34頁，共42頁。Effect SiteSpinal nerve rootSpinal anesthesia: Direct affectEpidural anesthesia: (1)Infiltrating in CSF (2)Spinal nerve艸鏈榀墚佤燙鸞劫蚶裁腸遣登耕漱犟喇裎锍梯疰卅腫笸襁坩墨啪岌諏脹臍鐘鐫炎奇腔攫釀鸞嵴十矛孜鐘諞琮押醌蛟味洵柄綦儡鏈暈垴俚筌脲僮龔泡孔淹醌第35頁，共42頁。Sequence of nerve blocksympathetic nerveEsthetic nerveMotor ner

31、ve杰屈鹱稀怩揍差蘸啁媚蚨咬啕詩砂箸奴冗需對妯柑絹櫧咨鐾邯磧申瓢視袤際攫沽省嚓拉礞撇究埸賑氚繳綰淆艱硐泛炭壯萊咽汶儻眶爛町楣秒蠟員軎閬籃釉蹬燠第36頁，共42頁。Differential block(Ropivacaine)Lower doses or concentrations may selectively inhibit pain sensation with minimal affect on muscle power. Some techniques of pain therapy, such as walking epidurals for labor pain use this effect, termed differen