股神经-坐骨神经联合阻滞与硬膜外阻滞对膝关节镜手术患者麻醉效果的影响

目的探讨股神经-坐骨神经联合阻滞与硬膜外阻滞对膝关节镜手术患者麻醉效果的影响,以期为膝关节镜手术患者麻醉方式的选择提供参考。方法择期行膝关节镜手术的患者的患者共计82例,年龄23~57岁,体重指数(BMI)17.2~25.5kg/m~2,ASA分级Ⅰ~Ⅱ级随机分为SF组和EA组,每组41例,分别记录两组患者感觉阻滞时间、感觉阻滞持续时间、运动阻滞时间、运动阻滞持续时间及麻醉前(T_0)、麻醉后10分钟(T_10)、麻醉后20分钟(T_20)、麻醉后30分钟(T_30)平均动脉压、心率。并记录患者局麻药中毒、穿刺点疼痛、术中低血压、术后恶心呕吐、术后尿潴留等麻醉相关并发症发生情况。结果在感觉阻滞方面,SF组患者感觉阻滞持续时间显著高于EA组(P0.05);在运动阻滞方面,SF组患者阻滞时间、阻滞持续时间均显著低于EA组(P=0.003、0.017)。在血流动力学方面,EA组患者麻醉后10、20、30分钟的MAP、HR显著低于SF组(P0.05)。在麻醉相关并发症方面,SF组患者术中低血压、术后恶心呕吐、术后尿潴留发生率显著低于EA组(P0.05)。结论股神经-坐骨神经联合阻滞能够提供良好的麻醉效果,具有运动阻滞时间短,对血流动力学影响小,并发症发生率低的诸多优点,是值得推荐用于膝关节镜手术的麻醉方式之一。     

坐骨神经联合股神经阻滞对老年糖尿病胫骨横向骨搬移术患者血流动力学的影响

目的:探讨坐骨神经联合股神经阻滞对老年糖尿病胫骨横向骨搬移术患者血流动力学的影响。方法:按照组间基线资料匹配的原则,将我院2017年4月至2020年4月期间121例接受胫骨横向骨搬移术的老年糖尿病患者进行分组,对照组60例予以硬膜外麻醉,观察组61例予以坐骨神经联合股神经阻滞,观察两组麻醉效果、血流动力学及不良反应。结...     

超声引导神经阻滞复合全身麻醉在胫骨骨折手术中的应用

目的探讨超声引导股神经加腘窝入路坐骨神经阻滞复合全身麻醉在胫骨骨折内固定手术中的应用。方法择期行胫骨骨折内固定手术的患者60例,随机分为两组,每组30例。A组全身麻醉,B组全麻诱导后行超声引导下股神经加腘窝入路坐骨神经阻滞。记录患者丙泊酚用量、唤醒时间、拔管时间、拔管后10min Ramsay镇静评分、拔管后30min VAS疼痛评分及术后并发症情况;记录术后24h患者满意度。结果 B组患者术中丙泊酚用量明显少于A组(P0.05);B组唤醒时间和拔管时间明显短于A组(P0.05)。拔管后30min,B组VAS疼痛评分明显低于,术后24h患者满意度明显高于A组(P0.05)。结论全麻复合超声引导股神经加腘窝入路坐骨神经阻滞可明显减少术中全麻药用量,有利于术后快速苏醒,并且可以减轻早期术后疼痛,减少术后镇痛药的使用。     

改良髂筋膜间隙联合腘窝坐骨神经阻滞在单侧大隐静脉曲张手术中的应用

目的观察改良髂筋膜间隙联合腘窝坐骨神经阻滞在单侧大隐静脉曲张手术中的麻醉效果。方法选择择期行单侧大隐静脉高位结扎加抽剥术患者60例,男32例,女28例,年龄42~76岁,ASAⅠ或Ⅱ级,采用随机数字表法将其分为改良髂筋膜间隙联合腘窝坐骨神经阻滞组(N组)和硬膜外阻滞组(E组),每组30例。N组先行腘窝坐骨神经阻滞,再在超声图像上确认髂筋膜和股神经位置,先行股神经阻滞,再在同一穿刺点从缝匠肌内侧缘开始,由外向内沿髂筋膜下给1%利多卡因10ml和0.5%罗哌卡因10ml,同时超声探头在腹股沟韧带水平向内移动,内侧达股动脉上方;E组采用L2~3间隙行硬膜外阻滞。记录两组阻滞前(T0)、阻滞后10min(T1)、30min(T2)、60min(T3)的SBP、DBP及HR;记录两组阻滞完成时间、感觉阻滞起效时间、术中麻黄碱使用情况、麻醉效果及术后48h恶心呕吐、头痛及尿潴留发生情况。结果与T0时比较,T2时E组的SBP和DBP明显降低(P0.05),T2时N组SBP和DBP明显高于E组(P0.05);N组感觉阻滞起效时间明显短于E组、术中麻黄碱使用率明显低于E组(P0.05);E组整体麻醉效果优于N组(P0.05),但两组麻醉效果优良率差异无统计学意义;术后48hN组尿潴留发生率明显低于E组(P0.05)。结论改良髂筋膜间隙联合腘窝坐骨神经阻滞用于单侧大隐静脉高位结扎加抽剥术中,麻醉效果良好,较硬膜外阻滞具有血流动力学影响小、术后并发症少及适应证更广等优点。     

腰丛-坐骨神经阻滞麻醉与腰硬联合麻醉用于下肢手术的血流动力学及临床效果观察

目的：探讨腰丛-坐骨神经阻滞麻醉在下肢手术中的血流动力学及临床应用效果。方法下肢手术患者共126例,按入院时间顺序将患者随机原则分为两组：实验组组(采用腰丛-坐骨神经阻滞麻醉)63例,对照组(采用腰硬联合麻醉)63例。观察指标①观察并记录两组患者手术麻醉前0、5、10、15、30、60、90分钟时的SBP、DBP、MAP、HR、SpO2的变化。②观察并记录两组患者感觉神经和运动神经阻滞起效和维持的时间。③观察并记录两组患者的术中使用麻黄碱的例数及术后头痛、恶心呕吐、尿潴留等相关不良反应。比较两种麻醉方法在下肢手术中的临床效果。结果①实验组SBP在麻醉给药10、15、30分钟后高于对照组,血压下降程度显著低于对照组,差异有统计学意义（P<0.05）;两组SBP在麻醉给药0、5、60、90分钟差异无统计学意义（P>0.05）;两组DBP、MAP、HR、SpO2在所有时段差异均无统计学意义(均P＞0．05)。②实验组感觉神经阻滞时间慢于对照组(P＜0．05),作用持续时间长于对照组(P＜0．05);同样运动神经阻滞时间慢于对照组(P＜0．05),作用持续时间长于对照组(P＜0．05)。③术中麻黄碱使用例数对照组明显高于实验组,差异有统计学意义(P＜0．05);术后相关并发症头痛、尿储留、恶心呕吐对照组明显高于实验组,差异有统计学意义(P＜0．05)。结论采用腰丛-坐骨神经联合阻滞的方式进行麻醉可有效降低手术的风险,且具有操作简便,容易掌握,适应症宽等特点,用于下肢手术值得临床推广。     

老年膝关节镜手术采用超声引导股神经联合坐骨神经阻滞麻醉的临床效果及不良反应

目的研究分析老年膝关节镜手术采用超声引导股神经联合坐骨神经阻滞麻醉的临床效果及不良反应。方法选取2013年1月至2015年12月本院收治的行膝关节手术治疗的老年患者60例。麻醉医师根据麻醉方法不同将所有患者随机平分为D组(股神经联合坐骨神经阻滞)和L组(腰麻)。记录两组患者手术时间,麻醉前、注射麻醉药物后5、10、20、30分钟的收缩压、舒张压、心率;两组患者术后3、10、20小时的VAS评分。比较两组麻醉方式的感觉、运动阻滞起效时间和持续时间。结果 D组麻醉后10、20、30分钟的收缩压和舒张压显著高于L组,D组术中血压无较大的变化,比较稳定,差异具有统计学意义(P<0.05);两组在麻醉前、注射麻醉药物后5、10、20、30分钟的心率无显著差异,比较无统计学意义(P>0.05)。两组术后的疼痛视觉模拟评分(VAS)比较,D组术后10、20小时的VAS评分显著低于L组,差异具有统计学意义(P<0.05);麻醉后感觉、运动阻滞方面,D组起效时间大于L组,而持续时间显著长于L组,差异具有统计学意义(P<0.05)。结论老年膝关节镜手术采用超声引导股神经联合坐骨神经阻滞麻醉的疗效显著,对患者术后早期功能练习具有促进作用,适合临床选择应用。     

高龄患者单侧下肢创伤后手术的麻醉方法比较

目的 探讨高龄患者单侧下肢创伤后手术麻醉的安全性. 方法 使用电脑随机编码、随机抽签将60例年龄为80岁～99岁的老年骨科手术患者随机分为神经阻滞组(N组)和轻比重腰麻组(S组),每组30例.N组行腰丛加坐骨神经阻滞麻醉,S组行轻比重腰麻,记录麻醉前及麻醉后1、3、5、10、15、30 min、1、2h、手术结束时患者的平均动脉压(mean arterial pressure,MAP)、心率(heart rate,HR)、血氧饱和度(blood oxygen saturation,SpO2);记录两组局麻药用量、麻醉起效时间、阻滞完善时间、辅助用药、感觉阻滞平面;观察两组麻醉效果、副作用和术后并发症等. 结果 N组麻醉后10 min MAP、HR、SpO2分别为(156±15) mm Hg(1 mm Hg=0.133 kPa)、(85±7)次/min、(98.5±1.5)％(P＞0.05);S组麻醉后10min MAP、HR、SpO2分别为(99±11)mmHg、(99±5)次/min、(98.5±1.5)％(P＜0.05);S组与N组MAP比较,P＜0.05; HR两组间比较,P＞0.05;N组SpO2麻醉后与术前比较,P＜0.01;S组SpO2麻醉后与术前比较,P＜0.05;两组间比较,P＞0.05;S组术中低血压的发生率及术后寒战、恶心、呕吐的发生率均升高(P＜0.05,P＜0.01). 结论 腰丛加坐骨神经阻滞麻醉比轻比重腰麻更安全,在高龄患者单侧下肢手术中患者血流动力学更平稳,并发症少,腰丛加坐骨神经阻滞麻醉可以作为高龄患者的下肢手术不适宜腰麻而又不愿全麻时的麻醉方法之一.     

超声引导下股神经-坐骨神经联合阻滞与硬膜外阻滞对老年膝关节置换术患者应激反应的影响

目的探讨股超声引导下股神经-坐骨神经联合阻滞与硬膜外阻滞对老年膝关节置换术患者应激反应的影响,以期为老年膝关节置换术患者麻醉方式的选择提供参考。方法选取本院2014年11月至2016年11月择期行单侧膝关节置换术的老年患者,共计70例。年龄65~78岁,体重指数(BMI)17.5~26.5kg/m~2,ASA分级Ⅰ~Ⅱ级。随机分为股神经-坐骨神经联合阻滞组(SF组)和硬膜外阻滞组(EA组),每组35例。分别记录两组患者麻醉前(T_0)、麻醉后即刻(T_1)、切皮时(T_2)、假体植入后(T_3)、出室前(T_4)收缩压(SBP)、舒张压(DBP)、心率(HR)及上述各时点白细胞计数(WBC)、皮质醇(COR)、C反应蛋白(CRP)、血糖(GLU)浓度。结果在血流动力学方面,EA组患者T1、T2时点SBP、DBP、HR显著低于SF组(P0.05)。而在T_3、T_4时点,EA组患者SBP、DBP、HR显著高于SF组(P0.05)。在应激反应方面,EA组患者T_3时点白细胞计数、血糖浓度显著高于SF组(P0.05)。结论与硬膜外阻滞相比,股神经-坐骨神经联合阻滞对血流动力学影响较小,并且能在一定程度上抑制老年膝关节置换术患者应激反应,具有一定的应用推广价值。     

神经刺激器定位腰丛-坐骨神经联合阻滞在老年人下肢手术的应用

目的探讨神经刺激器定位下行腰丛-坐骨神经联合阻滞在老年人下肢手术中的应用,以硬膜外麻醉作对照,观察其对老年病人血流动力学的影响和术后的不良反应。方法60例拟行单侧下肢手术的老年病人,随机分为腰丛-坐骨神经联合阻滞（NER）和硬膜外麻醉（EPI）。记录麻醉前,麻醉开始后15、30、45、60min,术后1h的收缩压（SBP）、舒张压（DBP）和心率（HR）,以及感觉、运动神经阻滞起效及恢复时间、镇痛维持时间、效果。结果麻醉开始后15min。EPI组病人DBP降低明显,随后30、45、60min及术后1hEPI组病人的SBP、DBP均明显低于NER组;NER组感觉、运动神经阻滞起效时间均小于EPI组,恢复时间明显长于EPI组。结论神经刺激器定位下行腰丛-坐骨神经联合阻滞,成功率高,血流动力学平稳,并发症少,起效迅速,镇痛时间长,是老年病人进行单侧下肢手术较好的麻醉方法。     

腰丛+骶丛神经阻滞与硬膜外麻醉对高龄股骨粗隆骨折患者麻醉效果及早期运动功能的影响

目的探讨腰丛+骶丛神经阻滞与硬膜外麻醉对高龄股骨粗隆骨折患者麻醉效果及早期运动功能的影响,以期为高龄股骨粗隆骨折患者麻醉方式的选择提供参考。方法择期行股骨粗隆骨折的老年患者共计150例,年龄65~79岁。随机分为腰丛+骶丛神经阻滞组(T组)和硬膜外麻醉组(C组),每组75例。记录两组患者麻醉后感觉完全阻滞时间、感觉阻滞持续时间、运动完全阻滞时间、运动阻滞持续时间及术中麻醉前(T0)、麻醉后10分钟(T1)、麻醉后20分钟(T2)、麻醉后30分钟(T3)平均动脉压(MAP)和心率(HR)变化。同时记录患者局麻药中毒、神经损伤、术中低血压、术后恶心呕吐(PONV)等麻醉相关并发症发生情况。结果 T组患者T1、T2、T3时点MAP、HR均显著高于C组(P0.05);T组患者感觉阻滞起效时间显著低于C组(P0.05),而T组患者感觉阻滞持续时间显著高于C组(P0.05);T组患者运动阻滞起效时间、运动阻滞持续时间均显著低于C组(P0.05);T组患者术中低血压、PONV发生率均显著低于C组(P0.05)。结论腰丛+骶丛神经阻滞能够提供与硬膜外麻醉相同的麻醉效果,并且对血流动力学及运动功能影响较小,并发症发生率低,值得在高龄股骨粗隆骨折患者中推广使用。     

Lateral popliteal sciatic nerve block: a single injection targeting the tibial branch of the sciatic nerve is as effective as a double-injection technique

BACKGROUND: Evidence indicating that single- and double-injection techniques for inducing a sciatic nerve block via a posterior subgluteal approach yield a similar success rate prompted us to investigate whether the two anesthetic techniques yield a similar success rate via a lateral approach. We also hypothesized that, owing to the peculiar anatomic features of the sciatic nerve at the popliteal level, a single injection via the lateral approach might induce effective anesthesia by targeting the tibial nerve only. METHODS: Ninety-six patients undergoing popliteal sciatic nerve block via a lateral popliteal approach for foot surgery were randomized to receive a single 30-ml injection of ropivacaine 7.5 mg/ml to block the tibial nerve (TN group, n= 32) or the common peroneal nerve (CPN group, n= 32), or two separate 15-ml injections (TN + CPN group, n= 32), after stimulation to evoke motor responses from the target nerves. RESULTS: The mean time to obtain a complete sensory blockade (surgical anesthesia) was shorter in the TN group than in the CPN and TN + CPN groups (14 +/- 7 min vs. 23 +/- 17 and 21 +/- 14 min, respectively; P < 0.05). The success rate was similar in the TN and TN + CPN groups (94%) and, 25 min after the initial injection, was already better in these groups than in the CPN group (94% vs. 75%; P < 0.05). CONCLUSIONS: A lateral popliteal sciatic nerve block obtained with a single 30-ml injection of ropivacaine 7.5 mg/ml after electrostimulation to locate the tibial nerve is as effective as multiple TN + CPN stimulation and injection, and local anesthesia has a significantly shorter onset time.     

Postoperative analgesia with continuous sciatic nerve block after foot surgery: a prospective, randomized comparison between the popliteal and subgluteal approaches

To compare the posterior popliteal and subgluteal continuous sciatic nerve block for anesthesia and acute postoperative pain management after foot surgery, 60 ASA physical status I and II patients undergoing elective orthopedic foot surgery were randomly assigned to either a Subgluteal group (n = 30) or Popliteal group (n = 30). Before surgery and after performing a femoral nerve block with 15 mL of 2% mepivacaine, we performed the sciatic nerve block with 20 mL of 0.75% ropivacaine using either a subgluteal or posterior popliteal approach, and the placement of a catheter came afterward. In the recovery room, the catheter was connected to a patient-controlled analgesia pump to infuse 0.2% ropivacaine (basal infusion rate of 5 mL/h, incremental bolus of 10 mL, and a lockout time of 60 min). There were no technical problems in catheter placement. Intraoperative efficacy of nerve block was similar in the two groups. Postoperative catheter displacement and occlusion were recorded in four patients in the Popliteal group and two patients in the Subgluteal group (P = 0.67). Both approaches provided similar postoperative analgesia. We conclude that the subgluteal approach is as effective and safe as the previously described posterior popliteal approach for continuous sciatic block and can be considered a useful alternative to anesthesia and acute postoperative analgesia after foot procedures. IMPLICATIONS: Comparing two different approaches for continuous sciatic nerve block after orthopedic foot surgery, this prospective, randomized study demonstrated that the subgluteal approach is as effective and safe as the previously described posterior popliteal approach, and can be considered a useful alternative to anesthesia and acute postoperative analgesia after foot procedures.     

The lateral approach to the sciatic nerve at the popliteal fossa: one or two injections?

It has not been proven whether one or multiple nerve stimulations and injections provide a higher rate of complete sensory block in both major sciatic nerve sensory distributions below the knee when a popliteal sciatic nerve block is performed using the lateral approach. This prospective, randomized, single-blinded study compared the success rate of the sciatic nerve block using this approach when one or both major components of this nerve (i.e., tibial nerve and common peroneal nerves) are stimulated in 50 patients undergoing foot or ankle surgery. In Group 1 STIM, 24 patients received a single injection of 20 mL of a mixture of 2% lidocaine and 0.5% bupivacaine with 1:200,000 epinephrine after foot inversion had been elicited. In Group 2 STIM (n = 26), 10 mL of the same solution was injected after stimulation of each sciatic nerve component. For patients with complete sensory motor block, there was no difference in onset between groups. However, Group 2 STIM showed a greater success rate compared with the Group 1 STIM (2 STIM: 88% vs 1 STIM :54%; P = 0.007). When two stimulations were used, the onset time of anesthesia in the cutaneous distribution of the common peroneal nerves was shorter than in the tibial nerve (17.5 vs 30 min; P < 0.0001). We conclude that a two-stimulation technique provides a better success rate than a single-injection technique when a popliteal sciatic nerve block is performed using the lateral approach with 20 mL of local anesthetic. IMPLICATIONS: A better success rate is achieved with a double stimulation technique than with a single injection for the sciatic nerve block via the lateral approach at the popliteal fossa when 20 mL of local anesthetics is used.     

A comparison of lateral popliteal versus lateral midfemoral sciatic nerve blockade using ropivacaine 0.5%

BACKGROUND AND OBJECTIVES: The midfemoral approach to the sciatic nerve (MF) is a new technique that has been used for postoperative analgesia after knee surgery. The aim of the present study was to compare efficacy, performance time, and patient acceptance of the midfemoral approach to that of the lateral approach at the level of the popliteal fossa (popliteal block [PB]). METHODS: Sixty-three patients were enrolled in this prospective, randomized study. Thirty-two patients received a lateral sciatic nerve block (group PB) and 31 patients a midfemoral block (group MF). Ropivacaine 0.5% (30 mL) was used in both groups. RESULTS: The quality of nerve blockade was comparable in both groups. Onset of sensory block for peroneal and tibial nerves was significantly shorter in group MF than in group PB, 5 (1-20) minutes and 5 (1-20) minutes versus 10 (1-40) minutes and 10 (1-45) minutes, respectively. Onset of motor block in both territories was also shorter in group MF compared with PB, 6 (2-35) minutes and 5 (2-55) minutes versus 15 (2-60) minutes and 15 (2-60) minutes, respectively (P <.05). There was no difference in duration of sensory and motor blockade, 16 (7-32) hours versus 16 (6-43) hours and 16 (8-32) hours versus 16 (6-25) hours. There was no significant difference between both groups with respect to difficulty of nerve block performance. Patient discomfort during needle puncture was also similar. CONCLUSIONS: The midfemoral approach to the sciatic nerve for ankle and foot surgery resulted in a reliable anesthetic, comparable to that of the lateral popliteal approach. This technique is simple, safe, and provides postoperative analgesia as effective as that obtained with the lateral approach.     

高龄患者下肢手术行外周神经阻滞效果分析

目的：在老年患者下肢手术过程中分别采用硬膜外麻醉与外周神经阻滞两种方法,并观察这两种麻醉方法的麻醉效果和安全性。方法选取2013年1月~2014年1月因下肢外伤就诊于我院的老年患者24例。按随机分组的方法分为外周神经阻滞组和硬膜外麻醉组,每组12例。外周神经阻滞组：在神经刺激器引导下行后路腰丛及坐骨神经阻滞。硬膜外麻醉组常规硬膜外麻醉。结果两组手术麻醉效果无显著差异（P＞0.05）。血流动力学改变：外周神经阻滞组患者阻滞前后及术毕均无明显波动,麻醉后15,30min两组心率、收缩压、舒张压及平均动脉压均有显著差异（P＜0.05）。镇痛时间：外周神经阻滞组明显长于硬膜外阻滞组。外周神经阻滞组起效时间明显短于硬膜外阻滞组,差异有统计学意义（P＜0.05）。外周神经阻滞组维持时间长于硬膜外阻滞组,差异有统计学意义（P＜0.05）。运动神经阻滞：外周神经阻滞组起效时间、维持时间均短于硬膜外阻滞,差异有统计学意义（P＜0.05）。结论外周神经阻滞可安全有效地应用于80岁以上高龄老人下肢手术。     

The effects of three different approaches on the onset time of sciatic nerve blocks with 0.75% ropivacaine

We studied three different injection techniques of sciatic nerve block in terms of block onset time and efficacy with 0.75% ropivacaine. A total of 75 patients undergoing foot surgery were randomly allocated to receive sciatic nerve blockade by means of the classic posterior approach (group classic; n = 25), a modified subgluteus posterior approach (group subgluteus; n = 25), or a lateral popliteal approach (group popliteal; n = 25). All blocks were performed with the use of a nerve stimulator (stimulation frequency, 2 Hz; intensity, 2-0.5 mA) and 30 mL of 0.75% ropivacaine. Onset of nerve block was defined as complete loss of pinprick sensation in the sciatic nerve distribution with concomitant inability to perform plantar or dorsal flexion of the foot. In the three groups, an appropriate sciatic stimulation was elicited at <0.5 mA. The failure rate was similar in the three groups (group popliteal: 4% versus group classic: 4% versus group subgluteus: 8%). The onset of nerve block was slower in group popliteal (25 +/- 5 min) compared with group classic (16 +/- 4 min) and group subgluteus (17 +/- 4 min; P < 0.001). There was no significant difference in the onset of nerve block between group classic and group subgluteus. No differences in the degree of pain measured at the first postoperative administration of pain medication were observed among the three groups. We conclude that the three approaches resulted in clinically acceptable anesthesia in the distribution of the sciatic nerve. The subgluteus and classic posterior approaches generated a significantly faster onset of anesthesia than the lateral popliteal approach. IMPLICATIONS: Comparing three different approaches to the sciatic nerve with 0.75% ropivacaine, the classic and subgluteal approaches exhibited a faster onset time of sensory and motor blockade than the lateral popliteal approach.     

Ultrasound-guided sciatic nerve block in the popliteal fossa for the postoperative pain control after Achilles' tendon repair

To assess the usefulness of ultrasound-guided sciatic nerve block in the popliteal fossa in the postoperative pain management after Achilles' tendon repair, we compared 15 patients managed by general anesthesia and sciatic nerve block (Group B) with 17 patients managed by general anesthesia alone (Group G). The time required for the nerve block was about 20 minutes on the average, and the success rate was 100%. No significant complication associated with the nerve block was observed. Fentanyl dosing for the postoperative analgesia was significantly smaller in the Group B. Although the postoperative analgesic requirement was comparable, the time to the first postoperative analgesic administration was significantly longer in the Group B. This retrospective study suggests that ultrasound-guided sciatic nerve block in the popliteal fossa provides safe and effective postoperative pain relief after Achilles' tendon repair.     

What is the minimum effective volume of local anesthetic required for sciatic nerve blockade? A prospective, randomized comparison between a popliteal and a subgluteal approach

For sciatic nerve blockade, no study has defined the optimal volume of local anesthetic required to block the nerve. The current, prospective, randomized investigation was designed to find a minimum volume of 1.5% mepivacaine required to block the sciatic nerve using the subgluteal and posterior popliteal approaches. A total of 56 patients undergoing foot surgery were randomly assigned to receive sciatic nerve block by means of a posterior subgluteal (group subgluteal, n = 28) or a posterior popliteal (group popliteal, n = 28) approaches. All blocks were performed with the use a nerve stimulator (stimulating frequency, 2 Hz, intensity 1.5-0.5 mA) and a perineural stimulating catheter. In all patients, plantar flexion of the foot was elicited at <0.5 mA, to maintain consistency among groups. The volume of local anesthetic used in each patient was based on the modified Dixon's up-and-down method. Complete anesthesia was defined as complete loss of pinprick sensation in the sciatic nerve distribution with concomitant inability to perform plantar or dorsal flexion of the foot 20 min after injection. The mean volume of local anesthetic required to block the sciatic nerve was 12 +/- 3 mL in the subgluteal group and 20 +/- 3 mL in the popliteal group (P < 0.05). The ED95 for adequate block of the sciatic nerve was 17 mL in the subgluteal group and 30 mL in the popliteal group. The authors conclude that a larger volume of local anesthetic is necessary to block the sciatic nerve at a more distal site (popliteal approach) as compared with a more proximal level (subgluteal approach).