Resuscitation strategies from bupivacaine-induced cardiac arrest

Objectives: Local anesthetic (LA) intoxication with cardiovascular arrest is a potential fatal complication of regional anesthesia. Lipid resuscitation has been recommended for the treatment of LA‐induced cardiac arrest. Aim of the study was to compare four different rescue regimens using epinephrine and/or lipid emulsion and vasopressin to treat cardiac arrest caused by bupivacaine intoxication. Methods: Twenty‐eight piglets were randomized into four groups (4 × 7), anesthetized with sevoflurane, intubated, and ventilated. Bupivacaine was infused with a syringe driver via central venous catheter at a rate of 1 mg·kg^?1·min^?1 until circulatory arrest. Bupivacaine infusion and sevoflurane were then stopped, chest compression was started, and the pigs were ventilated with 100% oxygen. After 1 min, epinephrine 10 μg·kg^?1 (group 1), Intralipid^® 20% 4 ml·kg^?1 (group 2), epinephrine 10 μg·kg^?1 + Intralipid^® 4 ml·kg^?1 (group 3) or 2 IU vasopressin + Intralipid^® 4 ml·kg^?1 (group 4) were administered. Secondary epinephrine doses were given after 5 min if required. Results: Survival was 71%, 29%, 86%, and 57% in groups 1, 2, 3, and 4. Return of spontaneous circulation was regained only by initial administration of epinephrine alone or in combination with Intralipid^®. Piglets receiving the combination therapy survived without further epinephrine support. In contrast, in groups 2 and 4, return of spontaneous circulation was only achieved after secondary epinephrine rescue. Conclusions: In cardiac arrest caused by bupivacaine intoxication, first‐line rescue with epinephrine and epinephrine + Intralipid^® was more effective with regard to survival than Intralipid^® alone and vasopressin + Intralipid^® in this pig model.     

意识与脑功能连接性:麻醉药物作用机制的研究进展

背景 功能连接性(整合),相对于解剖结构连接性,是指在耦联的神经系统中信号之间存在统计学上的依赖关系,近年来发现大脑不同区域之间的功能连接性与意识关系密切,而麻醉药物诱导意识丧失的机制很可能与功能连接性有关.目的 现从意识与大脑功能连接性角度对麻醉药物作用机制的研究进展作一综述.内容 静息态功能磁共振(resting state functional magnetic resonance imaging,rs-fMRI)在分析大脑功能连接性方面具有优势,多项研究应用rs-fMRI技术分析全身麻醉药物对脑区功能连接性的影响,提示麻醉药物的可能作用靶点为脑区功能连接性. 趋向 rs-fMRI技术的不断发展,为研究麻醉药物作用机制开辟了新的方向.     

全麻复合不同成分局麻药行双侧颈浅丛阻滞用于甲状腺手术临床效果观 察简

目的 比较全身麻醉术后芬太尼静脉镇痛与全身麻醉复合不同成分局麻药行双侧颈浅丛阻滞用于甲状腺手术的麻醉与镇痛效果.方法 选择择期行全麻甲状腺手术患者63例,随机分为三组,A组气管内全麻术后芬太尼静脉泵镇痛;BL组与BLF组气管内全麻复合双侧颈浅丛阻滞,BL组局麻药为0.375％盐酸罗哌卡因20 mL,BLF组局麻药为0.375％盐酸罗哌卡因20 mL＋1 μg/kg芬太尼.三组均采用相同药物诱导、气管插管、机械通气、术中静脉持续输注丙泊酚及瑞芬太尼,并间断静脉注射顺式阿曲库铵维持麻醉.分别记录麻醉前（T0）、切皮（T1）、切皮后15 min（T2）、缝皮（T3）、气管拔管时（T4）、气管拔管后5 min （T5）、气管拔管后10 min（T6）的血压及心率变化、麻醉药物用量、苏醒及气管拔管时间、术后镇痛时效及不良反应发生情况.结果 A组MAP和HR在T1-6明显高于BL组和BLF组,差异有统计学意义（P＜0.05）.BL组与BLF组比较差异无统计学意义（P＞0.05）.各时间点丙泊酚（10 mg/mL）及瑞芬太尼（40 μg/mL）输注速率,A组明显高于BL组和BLF组,差异有统计学意义（P＜0.05）.BL组与BLF组比较差异无统计学意义（P＞0.05）.剥离甲状腺至切除,各组比较差异无统计学意义（P＞0.05）.比较苏醒、拔管及开口回答问题时间,A组明显高于BL组和BLF组,差异有统计学意义（P＜0.05）.BL组与BLF组比较差异无统计学意义（P＞0.05）.术后2、4、6、12、24 h疼痛VAS评分,A组在2h内评分明显高于BL组和BLF组,差异有统计学意义（P＜0.05）.BL组术后4、6h评分高于A组与BLF组,差异有统计学意义（P＜0.05）.在2h后A组与BLF组疼痛时效差异无统计学意义（P＞0.05）.BL组4h内VAS评分与BLF组比较,差异无统计学意义（P＞0.05）.A组术后12例发生恶心、呕吐及嗜睡等不良反应明显高于BL组（3例）和BLF组（1例）,差异有统计学意义（P＜0.05）.BL组与Bu组比较差异无统计学意义（P＞0.05）.结论 全麻复合盐酸罗哌卡因与芬太尼混合液行双侧颈浅丛阻滞用于甲状腺手术围术期心血管系统平稳,麻醉药用量少,苏醒快且平稳无躁动,术后镇痛效果好,时间长,不良反应小,可安全用于甲状腺手术的麻醉.     

急性吸入性氯氰菊酯中毒13例临床分析

目的 通过分析氯氰菊酯吸入中毒的临床特点与救治经验,比较其与口服中毒的不同临床特点.方法 回顾性分析2012年6月群体性5％高效氯氰菊酯可湿粉吸入中毒13例患者的临床表现、影像学、实验室检查、治疗及转归.结果 除神经毒性及消化道损害之外,氯氰菊酯吸入中毒患者中,咽干(61.5％)、咳嗽咳痰(61.5％)、呼吸困难(30.8％)、气短(23.1％)等呼吸道症状明显.结论 氯氰菊酯吸入中毒可以造成明显的呼吸道损害,轻者表现为上呼吸道刺激症状或气管支气管炎症表现.     

An evaluation of the effectiveness of a computer simulation of anaesthetic uptake and distribution as a teaching tool

Gas Man is an interactive, microcomputer-based simulation and tutorial designed to teach the principles of anaesthetic uptake and distribution. Using two resident groups, one at a primary university-teaching hospital and the other at a medical school affiliated community hospital, the authors compared residents' knowledge of the subject prior to exposure to the tutorial and the average time spent using the program during a self-paced instruction period. Both groups not only significantly improved their knowledge of uptake and distribution 8 weeks after using this program, but wished to spend additional time with it, implying that it was a pleasant and satisfying way to learn. Computer simulation has the potential to be an important teaching tool in an anaesthesia residency training programme.     

导管诊治30年回顾

介绍了作支气管检查及治疗时的6种局部药选择，经2XK表X^2计算得出1％利多卡因较好。在心导管造影检查作全身麻醉时则用氯胺酮经导管注入取代1．25％硫喷妥钠加琥珀酰胆碱。对于预防导管检查所致的血栓形成，在插管前72小时先服双香豆素，并插管时再肝素化，用序贯试验方法得出此法比单独使用肝素要好。     

Comparison of transarterial and multiple nerve stimulation techniques for an initial axillary block by 45 mL of mepivacaine 1% with adrenaline

Background : The single-injection axillary block is rapidly performed but gives unpredictable results. Axillary block by multiple nerve stimulation technique (MNS) gives better results, but takes longer to perform. Transarterial (TA) injections of high doses of local anaesthetics are very successful. This double-blind study compared both block effectiveness and anaesthesiologic time consumption in 100 patients, having an axillary block by either TA or MNS techniques. Methods : 45 mL of 1% mepivacaine with adrenaline 5 μg/mL was used in each patient. Five mL was injected subcutaneously. In the TA group, 20 mL was injected deep to, and 20 mL superficial to the axillary artery. In the MNS group, four terminal motor nerves were electrolocated in the axilla, and injected with 10 mL each. Analgesia was assessed every 10 min and when needed supplemented after 30 min. The block was considered successful when analgesia was present in all sensory nerve areas distal to the elbow. Results : MNS group required 10δ2 min (meanδ1 SD) for the initial block performance compared with 7δ2 min for TA group, P<0.001. Latency of the initial block was shorter and the frequency of supplemental analgesia lower in the MNS group (mean 17 min and 12%), than in the TA group (25 min and 38%, respectively), P<0.001. All incomplete blocks were successfully supplemented by electrolocating the unblocked nerves. However, the total time to obtain 100% success rate was shorter in the MNS group (30 min), than in the TA group (38 min), P<0.001. The adverse effects (accidental intravascular injections and axillary haematomas) were fewer in the MNS group. Conclusion : In the hands of anaesthetists experienced in nerve electrolocation, the MNS technique of an initial axillary block by four separate injections of 10 mL of mepivacaine produces faster and more extensive block than the TA technique by two separate injections of 20 mL. Hence, the MNS technique requires fewer supplementary blocks and results in faster patient readiness for surgery than the TA technique.     

Midazolam-flumazenil versus propofol anaesthesia for scoliosis surgery with wake-up tests

Background : Wake-up tests may be necessary during scoliosis surgery to ensure that spinal function remains intact.
Methods : Intra- and postoperative wake-up tests were performed together with somatosensory cortical evoked potentials (SCEPs) monitoring in 40 patients randomized to either midazolam (M) or propofol (P) infusions for scoliosis surgery. Other anaesthetic medication was similar in both groups. At the surgeon's request, N₂O was turned off and midazolam or propofol infusions were discontinued. In the M group, flumazenil was given in refracted doses. Patients were asked to move hands and feet. The test was repeated immediately after the end of surgery.
Results : The median intraoperative wake-up times were 2.9 min in the M group and 16.0 min in the P group. The respective postoperative wake-up times were 1.8 and 13.9 min. The quality of both intra- and postoperative arousals was significantly better in the M group. Twelve patients in the P group could not be awakened intraoperatively within 15 min and were given nalox-one. One of these patients woke up violently and dislodged the endotracheal tube. Another patient in the P group had explicit recall of the test, but no pain. Five patients in the M group became resedated in the recovery room. Cost of anaesthetic drugs was similar in both groups. Satisfactory intraoperative SCEPs were recorded from 17 patients in each group. There were no neurological sequelae.
Conclusions : Wake-up tests can be conducted faster and better with midazolam-flumazenil sequence compared with propofol.     

Central nervous system toxicity in a patient receiving continuous intrapleural bupivacaine

A patient developed signs of central nervous system (CNS) toxicity during treatment of postthoracotomy pain with a continuous intrapleural bupivacaine infusion. This incident occurred after the patient's chest tube was clamped, without any decrease in the bupivacaine infusion rate. This is the first reported case of CNS toxicity in a patient receiving a continuous intrapleural bupivacaine infusion. Possible etiologies of this complication are discussed, as are ways to avoid such a complication in the future.