脊柱手术麻醉知识PPT课件.ppt

脊柱手术的麻醉,1,椎间盘问题,脊椎滑脱,需要手术治疗的脊柱问题,2,椎管狭窄,脊柱侧凸,驼背,脊髓肿瘤,需要手术治疗的脊柱问题,硬膜外血肿和脓肿,外伤,3,手术操作,椎板切开术,椎板切除术,椎间盘摘除术,4,手术操作,融合和固定,内固定术,5,术前评估,气道评估:张口度是否有困难插管史头颈活动度颈椎的稳定性与外科医生沟通是必须的,麻醉注意事项,6,呼吸系统病史:关注肺功能是否有损害体检:肺部感染的体征；严重的脊柱畸形胸部X线肺功能检查:脊柱侧凸血气分析心血管系统病史:高血压,糖尿病,充血性心力衰竭,冠心病体检:充血性心力衰竭体征心电图应激试验/心超,7,实验室检查（推荐）基本检查可选检查气道颈椎侧位片CT扫描肺部胸片肺功能检查血气分析(支气管扩张试验)肺功能检查(FEV1,FVC)肺弥散功能检查心血管心电图多巴酚丁胺应激Echo超声心动图潘生丁/铊扫描图血液检查CBC,electrolytes,Cr肝功能检查BUN,PT/PTTAlbumin,calcium(肿瘤疾病),8,神经系统评估整个神经系统评估都应记录在案1.颈椎手术的病人,麻醉科医生有责任在插管和放置体位时避免进一步的损伤2.肌肉萎缩增加术后反流误吸的风险3.脊髓损伤的程度和时间与围术期出现心血管和呼吸系统功能紊乱密切相关（小于3周,脊髓休克症状仍可出现；3周后可能出现自主神经反射失调,9,麻醉技巧,诱导:麻醉诱导的选择:i.v.orinhalation?病人的医疗状况气道颈椎稳定性肌松药的选择:SuccinylcholineorNDNMBs?病人的医疗状况气道返流误吸术中监测,10,麻醉技巧,插管Awakeorasleep?清醒气管插管:返流误吸可能插管后行神经评估:不稳定颈椎颈部稳定装置:halotractionDirectorfiber-opticlaryngoscopy?直接喉镜插管:包括可视喉镜等纤支镜:畸形:上胸段和颈部颈托固定的病人解剖异常:小下颌畸形，张口度小,11,上胸段和颈部手术的插管流程,12,麻醉维持维持稳定的麻醉深度避免因麻醉深度的突然改变而引起的血压波动Commonpractice:0.5MACIsoorsevocontinuousinfusionofpropofolcontinuousremifentanylorbolusopioids麻醉苏醒拔管:完全清醒对指令有反应气道自我保护恢复,麻醉技巧,13,脊柱手术中的特殊挑战,体位,术中监测,脊髓损伤,术后失明或视力低下(POVL),14,体位,PronepositionforC-spineprocedure,15,俯卧位引起的麻醉中的问题气道:气管导管扭曲或移位长时间手术导致上呼吸道水肿血管:上肢动脉和静脉阻塞股静脉扭曲，DVP腹腔内压:硬膜外静脉压出血神经:臂丛神经牵拉和受压尺神经受压:尺嘴鹰骨受压腓总神经受压:压迫腓骨小头股外侧皮神经损伤:压迫髂嵴头和颈:头颈屈曲或伸展过度眼部受压:视网膜损伤眼睛缺乏润滑和覆盖:角膜靠枕可能引起框上神经受压和损伤.颈部过度扭曲:臂丛神经损伤颈动脉受压,16,坐位,颈部椎板切除术病人手术应检查颈部活动情况应用坐位行颈部椎板切除术的比例逐渐增多坐位手术的缺点为静脉气栓的危险性增加坐位手术病人应防止神经、皮肤损伤注意颈部过度前屈可阻塞气道给病人以适当液体补充，且逐渐改变体位有助于防止低血压。,17,并发症静脉气栓,是脊柱手术严重并发症之一表现为无法解释的低血压、呼气末氮气水平升高早期诊断和处理可提高存活率,18,脊髓功能监测,截瘫是脊柱手术最严重的并发症常用唤醒试验和神经生理功能监测,19,术中监测,唤醒试验Wake-uptest体感诱发电位SSEPs动作诱发电位MEPs,20,Lighteninganesthesiaatanappropriatepointduringtheprocedureandobservingthepatientsabilitytomovetocommand.Itevaluatesthegrossfunctionalintegrityofthemotorpathway.Itwasfirstdescribedin1973.麻醉要求:简单和快速确切和快速拮抗药温柔唤醒试验过程中无痛Norecall,唤醒试验Wake-uptest,21,麻醉基数:吸入麻醉药咪唑安定丙泊酚瑞芬太尼缺点:需要患者配合插拔气管导管实践延长手术时间不能评估感觉通路,唤醒试验Wake-uptest,22,SSEPs,1.Themostcommonneurophysiologicalmethodformonitoringtheintra-operativespinalfunctionalintegrity2.ThestimulusappliedtotheperipheralN(tibialorulnar)3.Therecordingelectrodesplaced:cervicalregion,scalp,orepiduralspaceduringsurgery4.Baselinedataobtainedafterskinincision5.ResponsesarerecordedintermittentlyduringsurgeryAreductionintheamplitudeby50%andanincreaseinthelatencyby10%areconsideredsignificant.,23,TypicaltracingandL-10,SSEPsprovidesanindirectwayofmonitoringadjacentmotorpathwaysbecausemoreacuteimpairmentaffectsfunctionofmanyadjacentpathways,notjusttheposteriorcolumn.However,thiscannotbeguaranteed.2.Thebloodsupplyofthecorticospinalmotortractsdiffersfromthatofthedorsomedialsensorytracts.ItispossibletohavenormalSSEPsrecordingsthroughoutsurgery,buttohaveaparaplegicpatientpostoperatively.,24,SatisfactorymonitoringofearlycorticalSSEPsispossiblewith0.51.0MACisoflurane,desfluraneandsevoflurane.NitrousoxidepotentiatesthedepressanteffectofvolatileanestheticsIntravenousanestheticsgenerallyaffectSSEPslessthaninhaledanestheticsEtomidateandketamineincreasescorticalSSEPamplitudeClinicallyunimportantchangesinSSEPlatencyandamplitudeaftertheadministrationofopioids,麻醉药和SSEPs,25,SSEPs监测意义,EliminatingN2OfromthebackgroundanesthetichasbeenshowntoimprovecorticalamplitudesufficientlytomakemonitoringmorereliableSSEPlatencywilltake58mintostabilizeafterthestepchangesinvolatileanestheticconcentrationAddingetomidate,propofoloropioidsispreferabletobeginningN2OorincreasingvolatileanestheticconcentrationswhenanestheticdepthisinadequateIfavolatileanestheticisneverthelessneededrapidly,sevofluranepermitsfasterSSEPrecoveryaftertheacuteneedforvolatileanesthetichasbeenresolvedItiscriticaltoavoidsuddenchangesinvolatileanestheticdepthorbolusadministrationofintravenousanestheticsduringsurgicalmanipulationsthatcouldjeopardizetheintegrityoftheneuralpathwaysbeingmonitored,26,MEPs,Motorcortexstimulatedbyelectricalormagneticmeans,Myogenicresponses,Neurogenicresponses:peripheralNorspinalcord,27,麻醉药和MEPs,InhalationalanestheticssuppressmyogenicMEPsinadose-dependentmannerPairedpulsesoratrainofpulsescannotovercomethesuppressiveeffectsShouldbeavoided,orlimitedtoaverylowconcentrationduringthemonitoringofmyogenicMEPsN2Oappearstobelesssuppressivethanotherinhaledagents.Moderatedosesofupto50%N20havebeenusedsuccessfullytosupplementotheragentsduringmyogenicMEPmonitoring.Fentanyl,etomidate,andketaminehavelittleornoeffectonmyogenicMEPandarecompatiblewithintra-operativerecording.Benzodiazepines,barbiturates,andpropofolalsoproducemarkeddepressionofmyogenicMEP.However,successfulrecordingshavebeenobtainedduringpropofolanesthesiabycontrollingserumpropofolconcentrationsandincreasingstimulirates.,28,MyogenicMEPsareaffectedbythelevelofneuromuscularblockadeByadjustingacontinuousinfusionofmusclerelaxanttomaintainoneortwotwitchesinatrainoffour,reliableMEPresponseshavebeenrecordedMotorstimulationcanelicitmovement,andthiscaninterferewithsurgeryintheabsenceofneuromuscularblockadePhysiologicfactorssuchastemperature,systemicbloodpressure,PaO2,andPaCO2canalterSEPs/MEPsandmustbecontrolledduringintra-operativerecordings,麻醉药和MEPs,29,脊髓损伤,手术和麻醉引起的神经损伤并不局限于手术部位不良的手术体位可能导致截瘫和四肢瘫痪神经损伤最多见还是在手术部位,30,危险因素:手术种类和手术时间的长短脊髓血供（灌注压）潜在的脊柱病理改变术中神经组织的受压程度,脊髓损伤,31,预防:仔细放置体位维持SCPP:SCPP=MAPCSFP降低CSFP，脑脊液引流维持MAP?保持收缩压90mmHg药物:?甲强龙,门冬氨酸抑制剂(氯胺酮,镁)防止血肿形成仔细止血术前停用抗血小板药物术后立即使用肝素治疗,脊髓损伤,32,术后失明Post-operativevisualloss(POVL),POVL罕见但是灾难性1/1100俯卧位手术原因:视神经缺血(ION)(81%)视网膜中央动脉阻塞(13%)不明原因(6%).,33,病因:原因不明，但是和视网膜和或视神经血流灌注直接相关眼灌注压Ocularperfusionpressure(OPP):OPP=MAP-IOP.OPP:MAPand/orIOP危险因素:病人因素:肥胖高血压糖尿病贫血手术因素:长时间手术大量失血俯卧位低血压水中毒,视神经缺血(ION),34,临床表现:框周水肿,视网膜中央凹出现樱桃红斑点，单侧失明病因:直接眼球压迫3.可预防,视网膜中央动脉阻塞,35,脊柱侧弯,呼吸功能呼吸功能改变主要为通气/血流比例失调导致低氧血症年龄增长，由于代偿功能下降，而出现二氧化碳分压升高长期低氧血症、高二氧化碳分压，使肺血管收缩，导致肺血管不可逆性改变和肺动脉高压,36,脊柱侧弯