1、脊柱手术的麻醉,椎间盘问题,脊椎滑脱,需要手术治疗的脊柱问题,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,手术操作,椎板切开术,椎板切除术,椎间盘摘除术,手术操作,融合和固定,内固定术,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,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,实验室检查（推荐）基本检查 可选检查气道 颈椎侧
2、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/PTT Albumin, calcium (肿瘤疾病),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
3、出现自主神经反射失调,麻醉技巧,诱导: 麻醉诱导的选择: i.v. or inhalation ?病人的医疗状况气道颈椎稳定性肌松药的选择:Succinylcholine or NDNMBs ?病人的医疗状况气道返流误吸术中监测,麻醉技巧,插管Awake or asleep?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: halo traction Direct or fiber-optic laryngoscopy?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,上胸段和颈部手术的插管流程,麻醉维持维持稳定
4、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Common practice: 0.5 MAC Iso or sevo continuous infusion of propofolcontinuous remifentanyl or bolus opioids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,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),体位,Prone position for C-spine procedure,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
5、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,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。,并发症 静脉气栓,是脊柱手术严重并发症之一 表现
6、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,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,术中监测,唤醒试验Wake-up test 体感诱发电位SSEPs动作诱发电位MEPs,Lightening anesthesia at an appropriate point during the procedure and observing the patients ability to move to command. It evaluates the gross functional integrity of the motor pathw
7、ay. It was first described in 1973. 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No recall,唤醒试验Wake-up test,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-up test,SSEPs,1. The most common neurophysiological method for monitoring the intra-operative spinal functional integrity2. The stimulus ap
8、plied to the peripheral N (tibial or ulnar)3. The recording electrodes placed: cervical region, scalp, orepidural space during surgery4. Baseline data obtained after skin incision5. Responses are recorded intermittently during surgeryA reduction in the amplitude by 50% and an increase in the latency
9、 by 10% are considered significant.,Typical tracing and L-10,SSEPs provides an indirect way of monitoring adjacent motor pathways because more acute impairment affects function of many adjacent pathways, not just the posterior column. However, this cannot be guaranteed. 2. The blood supply of the co
10、rticospinal motor tracts differs from that of the dorsomedial sensory tracts. It is possible to have normal SSEPs recordings throughout surgery, but to have a paraplegic patient postoperatively.,Satisfactory monitoring of early cortical SSEPs is possible with 0.51.0 MAC isoflurane, desflurane and se
11、voflurane. Nitrous oxide potentiates the depressant effect of volatile anesthetics Intravenous anesthetics generally affect SSEPs less than inhaled anesthetics Etomidate and ketamine increases cortical SSEP amplitude Clinically unimportant changes in SSEP latency and amplitude after the administrati
12、on of opioids,麻醉药和 SSEPs,SSEPs 监测意义,Eliminating N2O from the background anesthetic has been shown to improve cortical amplitude sufficiently to make monitoring more reliable SSEP latency will take 58 min to stabilize after the step changes in volatile anesthetic concentration Adding etomidate, propo
13、fol or opioids is preferable to beginning N2O or increasing volatile anesthetic concentrations when anesthetic depth is inadequate If a volatile anesthetic is nevertheless needed rapidly, sevoflurane permits faster SSEP recovery after the acute need for volatile anesthetic has been resolved It is cr
14、itical to avoid sudden changes in volatile anesthetic depth or bolus administration of intravenous anesthetics during surgical manipulations that could jeopardize the integrity of the neural pathways being monitored,MEPs,Motor cortex stimulated by electrical or magnetic means,Myogenic responses,Neur
15、ogenic responses: peripheral N or spinal cord,麻醉药和 MEPs,Inhalational anesthetics suppress myogenic MEPs in a dose-dependent manner Paired pulses or a train of pulses cannot overcome the suppressive effects Should be avoided, or limited to a very low concentration during the monitoring of myogenic ME
16、Ps N2O appears to be less suppressive than other inhaled agents. Moderate doses of up to 50% N20 have been used successfully to supplement other agents during myogenic MEP monitoring. Fentanyl, etomidate, and ketamine have little or no effect on myogenic MEP and are compatible with intra-operative r
17、ecording. Benzodiazepines, barbiturates, and propofol also produce marked depression of myogenic MEP. However, successful recordings have been obtained during propofol anesthesia by controlling serum propofol concentrations and increasing stimuli rates.,Myogenic MEPs are affected by the level of neu
18、romuscular blockade By adjusting a continuous infusion of muscle relaxant to maintain one or two twitches in a train of four, reliable MEP responses have been recorded Motor stimulation can elicit movement, and this can interfere with surgery in the absence of neuromuscular blockade Physiologic fact
19、ors such as temperature, systemic bloodpressure, PaO2, and PaCO2 can alter SEPs/MEPs and must be controlled during intra-operative recordings,麻醉药和 MEPs,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,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,预防: 仔细放置体位 维持 SCPP: SCPP = MAP
20、CSFP 降低CSFP ，脑脊液引流 维持MAP ? 保持收缩压 90 mm Hg 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,术后失明Post-operative visual loss (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%).,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Ocular perfusion pressure (OPP):OPP= MAP - IOP.
21、OPP : MAP and /or IOP 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),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,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,脊柱侧弯,心血管功能 右心室肥厚，肺血管发生高血压性改变 还可伴有先天性心脏疾患。 术前评估 发现并存的心肺疾患和病
22、变程度 应检查有无神经功能缺陷 还应了解有无气管插管困难,脊柱侧弯,麻醉处理 应考虑包括手术体位 手术时间较长，血液和液体的替代治疗 维护脊髓功能的完整 防治静脉气栓 麻醉期间给予适当监测和保持静脉畅通十分重要。 失血 减少出血和输血的措施包括合适体位、术中自体血回收、行控制性低血压术、术中血液稀释等。,脊髓外伤病人的麻醉,脊髓外伤约一半发生于颈椎水平 对疑有脊髓损伤的病人应快速检查神经系统功能 同时应立即检查有无呼吸功能不全、气道梗阻肋骨骨折、胸部和颌面部外伤,脊髓外伤病人的麻醉,气管插管 急性颈椎损伤最主要的死亡原因是呼吸衰竭 在可能的情况下，应在确定病人上、下肢随意运动的前提下进行静脉置管、全麻诱导、气管插管和摆放体位,脊髓外伤病人的麻醉,维护脊髓完整 应维持良好的脊髓供血，应避免过度通气，应用神经生理监测 呼吸功能支持 心血管功能支持 损伤部位以下的交感性血管张力丧失 避免应用琥珀胆碱 在损伤后48h内应用琥珀胆碱是安全的；在脊髓损伤后4周至5个月血清钾升高最为明显,脊髓外伤病人的麻醉,控制体温 脊髓损伤平面以下体温变化与交感张力分离，导致体温随环境温度而变化 自主反射增强 表现特征为严重的阵发性高血压、心动过缓、心律失常 损害平面以下的皮肤血管收缩，损害平面以上的皮肤血管扩张,Thank You,
