周围神经刺激器用于闭孔神经阻滞在膀胱肿瘤电切术中的应用

闭孔神经阻滞是膀胱肿瘤电切手术时预防闭孔神经反射的最有效方法。但由于是盲式操作，临床上麻醉失败或阻滞不全时有发生。我院2001年2月～2003年5月采用神经刺激器定位行闭孔神经阻滞，取得满意疗效。     

周围神经刺激器在闭孔神经阻滞中的应用

闭孔神经阻滞是膀胱肿瘤电切手术前预防闭孔神经反射的最有效方法,但由于是盲式操作,临床上麻醉失败或阻滞不全也时有发生.我们利用神经刺激器定位行闭孔神经阻滞取得满意效果,现报道如下.     

经闭孔行闭孔神经阻滞对预防膀胱侧壁肿瘤电切时闭孔神经反射的作用

目的探讨经闭孔行闭孔神经阻滞对预防膀胱侧壁肿瘤电切时闭孔神经反射的作用。方法回顾性分析67例膀胱侧壁浅表性肿瘤行经尿道膀胱肿瘤电切术的患者资料,根据术中是否行闭孔神经阻滞分为闭孔神经阻滞组（35例）和对照组（32例）,其中闭孔神经阻滞组术中辅以经闭孔法闭孔神经阻滞,而对照组未行闭孔神经阻滞。比较两组术中闭孔神经反射发生率、膀胱穿孔率、手术时间、及出血量,并术后随访观察肿瘤的复发情况。结果两组术中电切时间、出血量、术后1年肿瘤复发率均无统计学差异,但闭孔神经阻滞组闭孔神经反射率及膀胱穿孔率较对照组明显降低。结论经闭孔行闭孔神经阻滞能有效预防膀胱侧壁肿瘤电切时闭孔神经反射,可降低膀胱穿孔率,其操作要点是选择准确的穿刺点、掌握好穿刺方向和深度。     

膀胱肿瘤电切术中行闭孔神经阻滞防止闭孔神经反射的效果分析

目的 探讨经尿道膀胱肿瘤电切术中采用闭孔神经阻滞防止闭孔神经反射的临床效果.方法 对214例膀胱癌患者行经尿道电切术,治疗组113例在腰-硬联合麻醉基础上进行闭孔神经阻滞,而对照组101例仅行单纯腰-硬联合麻醉.结果 治疗组闭孔神经反射发生率（9.7%）明显低于对照组（22.8%）（P〈0.05）,两组复发率差异无统计学意义（21.2% vs 25.7%,P＆gt;0.05）.结论 在经尿道膀胱肿瘤电切术中采取闭孔神经阻滞能明显减少闭孔神经反射的发生,提高手术的安全性和有效性,临床效果良好.     

经尿道膀胱肿瘤电切术中闭孔神经反射的临床研究

目的 探讨利用针形电极诱发神经反射、弧形切割并结合肿瘤基底部闭孔神经阻滞在经尿道膀胱肿瘤电切术(TURBT)中预防闭孔神经反射的效果.方法 2008年4月至2010年10月,82例膀胱肿瘤患者在椎管麻醉下行TURBT,对针形电极弧形切割诱发的闭孔神经反射采用肿瘤基底部闭孔神经阻滞.结果 术中针形电极诱发闭孔神经反射27例,通过肿瘤基底部深肌层水平方向浸润注射利多卡因后闭孔神经反射消失.27例均顺利完成手术,未发现膀胱壁破裂、严重出血等并发症.结论 针形电极弧形切割结合肿瘤基底部闭孔神经阻滞可有效预防TURBT术中闭孔神经反射,降低膀胱穿孔及严重出血的发生率.该方法简便易行,具有一定临床应用价值.     

经尿道膀胱肿瘤电切术2种麻醉方法的比较

目的探讨双侧闭孔神经阻滞在经尿道膀胱肿瘤电切术（transurethral resection of bladder tumor,TURBt）的安全性与有效性。方法77例膀胱肿瘤按时间顺序分为2组：2003年4月～2004年10月46例为硬膜外麻醉组,2004年10月～2005年7月31例为硬膜外联合闭孔神经阻滞组。比较2组TURBt闭孔神经反射发生率和膀胱穿孔发生率。结果硬膜外麻醉组出现闭孔反射25例（其中强烈反射11例）,闭孔反射发生率为54.3%（25/46）,直接由闭孔反射导致的膀胱穿孔8例,膀胱穿孔发生率17.3%（8/46）;硬膜外联合闭孔神经阻滞组发生轻微闭孔反射3例,发生率9.9%（3/31）,膀胱穿孔发生率3.2%（1/31）,硬膜外麻醉组闭孔神经反射发生率明显高于硬膜外联合闭孔神经阻滞组（χ^2=15.970,P=0.000）;但2组膀胱穿孔发生率分别为17.3%（8/46）、3.2%（1/31）无统计学差异（χ^2=2.359,P=0.125）。结论硬膜外麻醉联合双侧闭孔神经阻滞麻醉能有效地减少闭孔神经反射的发生,提高TURBt的安全性。     

经尿道膀胱肿瘤电切术中预防闭孔神经反射致膀胱穿孔的不同方法介绍

目的总结经尿道膀胱肿瘤电切术中,应用各种闭孔神经反射预防方法避免膀胱穿孔的经验。方法回顾性分析总结我院自2007年1月至2009年12月在经尿道膀胱肿瘤电切术中,应用闭孔神经反射预防方法的临床资料。经尿道膀胱肿瘤电切术的患者186例,男性115例,女性71例,年龄27～87岁,平均54岁。膀胱左侧或右侧壁单发肿瘤134例,膀胱多发表浅性肿瘤52例,根据患者采用的麻醉方法被分成三组,其中第一组应用硬膜外麻醉和肌松药及面罩给氧56例,第二组应用全身麻醉104例,第三组应用硬膜外麻醉和闭孔神经阻滞麻醉26例。结果 186例患者中,第一组有6例出现轻微的闭孔神经反射,未造成膀胱穿孔,有5例出现严重的闭孔神经反射,造成轻微的膀胱穿孔4例,不需要膀胱修补,造成2例严重的膀胱穿孔,1例大出血,需要进行膀胱修补术。第二组出现2例轻微的闭孔神经反射,造成轻微的膀胱穿孔,不需要膀胱修补。第三组造成1例严重的膀胱穿孔,需要进行膀胱修补术。结论硬膜外麻醉是不能抑制闭孔神经反射的,肌松药的应用可以抑制膀胱肌肉的收缩,对大的表浅性膀胱肿瘤或多发的表浅性膀胱肿瘤,应用全身麻醉是非常适合的。闭孔神经阻滞麻醉和硬膜外麻醉的联合应用是经济的方法,但闭孔神经阻滞不全,效果不佳是出现闭孔神经反射的原因。     

超声联合神经刺激仪引导利多卡因闭孔神经阻滞的半数有效容量

目的测定超声联合神经刺激仪引导下1.5%利多卡因闭孔神经阻滞(ONB)抑制经尿道膀胱肿瘤电切术(TURBT)中闭孔神经反射的半数有效容量(EV50)。方法术前根据膀胱镜检或CT检查结果确定需行闭孔神经阻滞的择期经尿道膀胱肿瘤电切术患者27例,ASAⅠ或Ⅱ级,年龄18～80岁,BMI 19～30kg/m2,在超声及外周神经刺激仪引导下用1.5%利多卡因行ONB,以大腿内收肌力、术中腿动情况等判定阻滞效果。利多卡因容量根据序贯法确定,起始容量为10ml,相邻容量比为1.2。计算利多卡因EV50及95%CI。结果超声及外周神经刺激仪引导下闭孔神经阻滞1.5%利多卡因EV50为5.26ml,95%CI为4.99～5.54ml。结论超声及外周神经刺激仪引导下行闭孔神经阻滞抑制经尿道膀胱肿瘤电切术中闭孔神经反射的1.5%利多卡因半数有效容量为5.26ml。     

超声引导下腹股沟径路闭孔神经阻滞的应用

目的观察超声引导下腹股沟径路闭孔神经阻滞在经尿道膀胱肿瘤电切术中预防闭孔神经反射的临床效果和并发症。方法行经尿道膀胱肿瘤电切术患者50例,随机分为2组：超声引导腹股沟径路闭孔神经阻滞组（UONB组,25例）和传统闭孔神经阻滞组（TONB组,25例）。闭孔神经阻滞前后分别测定阻滞侧大腿内收肌力量。记录两种闭孔神经阻滞方法成功率及副作用发生情况等。结果 UONB组和TONB组患者阻滞侧大腿内收肌力量闭孔神经阻滞后分别为52±7mmHg和66±19mmHg,UONB组显著小于TONB组（P=0.001）。UONB组阻滞成功率为97.4%,显著高于TONB组（74.2%）（P=0.01）。结论超声引导闭孔神经阻滞成功率高,可以安全、有效的预防膀胱肿瘤电切术闭孔神经反射。     

超声引导下闭孔神经阻滞在经尿道膀胱肿瘤电切术中预防闭孔神经反射的效果

目的通过对比不同麻醉方式下闭孔神经反射的发生情况,探讨经尿道膀胱肿瘤电切术中预防闭孔神经反射的有效方式。方法选取需行经尿道膀胱肿瘤电切术的膀胱侧壁肿瘤患者160例,男134例,女26例,ASAⅠ~Ⅲ级,随机分为四组:全凭静脉麻醉组(G组),腰-硬联合麻醉组(C组),腰-硬联合麻醉复合静脉麻醉组(V组),腰-硬联合麻醉复合闭孔神经阻滞(obturator nerve block,ONB)组(O组),每组40例。记录不同麻醉方式下闭孔神经反射的发生情况。结果O组闭孔神经反射发生率(7.5%)明显低于C组(32.5%,P=0.005)和V组(40.0%,P=0.001),与G组闭孔神经反射发生率(5.0%)差异无统计学意义(P=0.644)。结论腰-硬联合麻醉复合闭孔神经阻滞与全凭静脉麻醉均可有效预防闭孔神经反射的发生。     

A report on 107 cases of obturator nerve block

The obturator nerve passes in close proximity to the inferolateral bladder wall. Transurethral resection of bladder tumors close to these areas may stimulate the obturator nerve, causing violent adductor contraction and possible inadvertent bladder perforation. To avoid this reaction, local anesthetic blockade of the obturator nerve as it passes through the obturator canal is effective to stop adductor spasm during spinal anesthesia. We performed obturator nerve block in 107 cases by use of insulated needle and nerve stimulator, and measured the depth of the obturator nerve and that of the pubic tubercle. Obesity index was positively correlated with the depth of the obturator nerve as well as the pubic tubercle. However, no correlation was found between the obesity index and the difference of the depth of the obturator nerve and the depth of the pubic tubercle. It is suggested that if the needle is advanced in the direction of the obturator canal about 40mm further after reaching the pubic tubercle, the needle reaches the obturator nerve.     

Life-threatening haemorrhage following obturator artery injury during transurethral bladder surgery: a sequel of an unsuccessful obturator nerve block

In spite of prior blockade of the obturator nerve with 1% mepivacaine (8 ml) utilizing a nerve stimulator, violent leg jerking was evoked during transurethral electroresection of a bladder tumour approximately 1 h after the blockade in a 68-year-old man. The patient became severely hypotensive immediately following the jerking, and a large lower abdominal swelling concurrently developed. The urgent laparotomy indicated that the left obturator artery was severely injured by the resectoscope associated with the bladder perforation, causing acute massive haemorrhage. The patient recovered uneventfully after adequate surgery. Investigation of the literature suggested that both our nerve stimulation technique and anatomical approach were appropriate. It was therefore unlikely that our block resulted in failure because of an inappropriate site for deposition of the anaesthetic. However, consensus does not appear to have been obtained as to the concentration and volume of the anaesthetic necessary for prevention of the obturator nerve stimulation during the transurethral procedures. The concentration and volume of mepivacaine we used might have been too low and/or small, respectively, to profoundly block all the motor neuron fibres of the nerve. Alternatively, stimulation of the obturator nerve might occur because of the presence of some anatomical variant, such as the accessory obturator nerve or its abnormal branching. In conclusion, some uncertainty appears to exist in the effectiveness of the local anaesthetic blockade of the obturator nerve. In order to attain profound blockade of the motor neuron fibres of the obturator nerve and thereby prevent the thigh-adductor muscle contraction which can lead to life-threatening situations, we recommend, even with a nerve stimulator, to use a larger volume of a higher concentration of local anaesthetic with a longer duration in the obturator nerve block for the transurethral procedures.     

An evaluation of the cutaneous distribution after obturator nerve block.

In 1973, Winnie et al. introduced the inguinal paravascular three-in-one block, which allegedly provides anesthesia of three nerves--the femoral, lateral cutaneous femoral, and obturator nerves--with a single injection. This concept was undisputed until the success of the obturator nerve block was reassessed by using evidence of adductor weakness rather than cutaneous sensory blockade, the latter being variable in its distribution and often absent. We performed this study, therefore, to evaluate the area of sensory loss produced by direct injection of local anesthetic around the obturator nerve. A selective obturator nerve block with 7 mL of 0.75% ropivacaine was performed in 30 patients scheduled for knee surgery. Sensory deficit and adductor strength were evaluated for 30 min by using sensory tests (cold and light-touch perception) and the pressure generated by the patient's squeezing a blood pressure cuff placed between the knees. Subsequently, a three-in-one block was performed, and the sensory deficit was reassessed. The obturator nerve block was successful in 100% of cases. The strength of adductors decreased by 77% +/- 17% (mean +/- SD). In 17 patients (57%), there was no cutaneous contribution of the obturator nerve. The remaining 7 patients (23%) had an area of hypoesthesia (cold sensation was blunt but still present) on the superior part of the popliteal fossa, and the other 6 (20%) had sensory deficit located at the medial aspect of the thigh. The three-in-one block resulted in blockade of the lateral aspect of the thigh in 87% of cases, whereas the anteromedial aspect was always anesthetized. By use of magnetic resonance imaging in eight volunteers, we demonstrated that the obturator nerve has already divided into its two branches at the site of local anesthetic injection. However, the injection of blue dye after having simulated the technique in five cadavers showed that the fluid regularly spread to both branches. We conclude that after three-in-one block, a femoral nerve block may have been assessed as an obturator nerve block in 100% of cases when testing the cutaneous distribution of the obturator nerve on the medial aspect of the thigh. IMPLICATIONS: Previous studies reporting an incidence of obturator nerve block after three-in-one block may have mistaken a femoral nerve block for an obturator nerve block in 100% of cases when the cutaneous distribution of the obturator nerve was assessed on the medial aspect of the thigh. The only way to effectively evaluate obturator nerve function is to assess adductor strength.     

Inability to consistently elicit a motor response following sensory paresthesia during interscalene block administration

BACKGROUND: Two methods of nerve block based on eliciting neural feedback with the block needle currently exist. The paresthesia technique uses sensory feedback to ascertain that the needle tip is close to the nerve. By contrast, a peripheral nerve stimulator makes use of motor responses to electrical stimulation. The relation of motor responses to an electrical peripheral nerve stimulator and sensory nerve contact (paresthesia) had not been studied. METHODS: Thirty consecutive unpremedicated patients who presented for shoulder surgery with interscalene block anesthesia were prospectively studied. Interscalene block was performed by the single paresthesia method of Winnie, using an insulated or non-insulated needle connected to a peripheral nerve stimulator with the power off. At the precise point of paresthesia, the peripheral nerve stimulator was turned on, and the current was slowly increased to 1.0 mA with a pulse width of 0.2 ms. Presence and location of any motor responses were observed and recorded. RESULTS: All patients had easily elicited paresthesias. The site of first paresthesia was to the shoulder in 73% of patients. Only 30% of patients exhibited any motor response to electrical stimulation up to 1.0 mA. There was no relation between site of paresthesia and associated motor nerve response. CONCLUSION: Elicitation of paresthesia does not translate to an ability to elicit a motor response to a peripheral nerve stimulator in the majority of patients.     

Inability to Consistently Elicit a Motor Response following Sensory Paresthesia during Interscalene Block Administration

Background: Two methods of nerve block based on eliciting neural feedback with the block needle currently exist. The paresthesia technique uses sensory feedback to ascertain that the needle tip is close to the nerve. By contrast, a peripheral nerve stimulator makes use of motor responses to electrical stimulation. The relation of motor responses to an electrical peripheral nerve stimulator and sensory nerve contact (paresthesia) had not been studied.

Methods: Thirty consecutive unpremedicated patients who presented for shoulder surgery with interscalene block anesthesia were prospectively studied. Interscalene block was performed by the single paresthesia method of Winnie, using an insulated or noninsulated needle connected to a peripheral nerve stimulator with the power off. At the precise point of paresthesia, the peripheral nerve stimulator was turned on, and the current was slowly increased to 1.0 mA with a pulse width of 0.2 ms. Presence and location of any motor responses were observed and recorded.

Results: All patients had easily elicited paresthesias. The site of first paresthesia was to the shoulder in 73% of patients. Only 30% of patients exhibited any motor response to electrical stimulation up to 1.0 mA. There was no relation between site of paresthesia and associated motor nerve response.     

Sonographic imaging of the obturator nerve for regional block

BACKGROUND AND OBJECTIVES: Today, there is a growing appreciation of the importance of the obturator nerve in clinical anesthesia. The aim of this study is to describe the ultrasound appearance of the obturator nerve for potential utility in guiding these nerve blocks. METHODS: We scanned left and right inguinal regions of 20 volunteers lateral and distal to the pubic tubercle (PT) and assessed visibility, size and shape, and depth from the skin of common obturator nerves and their associated divisions. In addition to the volunteer study, we retrospectively reviewed a clinical series of obturator nerve blocks performed with ultrasound guidance and nerve stimulation. RESULTS: The obturator nerve can be sonographically visualized by scanning along the known course of the nerve; the anterior division characteristically converges toward the posterior division along the lateral border of the adductor brevis muscle to form the common obturator nerve more proximally. In the set of 20 volunteers, 25% (10/40) of common, 85% (34/40) of anterior, and 87.5% (35/40) of posterior obturator nerves were sonographically identified. The common obturator nerve was visualized 1.3 +/- 1.5 cm distal and 2.3 +/- 1.2 cm lateral to the PT. Divisions were visualized 2.1 +/- 2.0 cm distal and 2.1 +/- 1.2 cm lateral to the PT. The nerves (common, anterior, and posterior) averaged 2.7 +/- 1.2 mm, 1.4 +/- 0.6 mm, and 1.7 +/- 0.6 mm in anterior-posterior dimension and 9.0 +/- 4.3 mm, 9.6 +/- 3.9 mm, and 10.9 +/- 4.1 mm in medial-lateral dimension and were 25.9 +/- 7.6 mm, 15.5 +/- 3.9 mm, and 29.3 +/- 7.9 mm below the skin surface. The common obturator nerve and its anterior and posterior divisions are all relatively flat nerves with average anterior-posterior/medial-lateral dimension ratios of 0.32, 0.18, and 0.18, respectively. In the clinical series, nerve identification was confirmed with nerve stimulation (n = 6 block procedures, mean threshold stimulating current for evoked adductor contraction = 0.70 +/- 0.14 mA). CONCLUSIONS: The obturator nerve and its divisions are the flattest peripheral nerves yet described with ultrasound imaging. Knowledge of the obturator nerve's ultrasound appearance facilitates localization of this nerve for regional block and may increase success of such procedures.     

Ultrasound guidance with nerve stimulation reduces the time necessary for resident peripheral nerve blockade

BACKGROUND AND OBJECTIVES: Educating residents in peripheral nerve blockade may impact the efficiency of a busy regional anesthesia service. Ultrasound guidance may affect the efficiency and effectiveness of nerve block. We examined the impact of ultrasound guidance on resident performance of peripheral nerve block in a regional anesthesia rotation. METHODS: An existing de-identified database was used for retrospective analysis of resident performance of interscalene, axillary, femoral, and popliteal nerve blocks, by peripheral nerve stimulator guidance alone and by nerve stimulator aided by ultrasound. The primary variable examined was the time required to perform the block. Others variables included (1) number of needle insertions; (2) proportion of blocks in which there was a blood vessel puncture; and (3) block efficacy. Peripheral nerve-stimulator blocks were guided by surface anatomy and motor stimulation, refined to 0.2 to 0.5 mA of current before injection of local anesthetic, while ultrasound nerve stimulator blocks were confirmed using a current of 0.5 mA. RESULTS: Ultrasound-aided blocks required less time to perform (median = 1.8 min) than nerve stimulator-guided blocks (median = 6.5 min, P < .001). More needle insertions were required for nerve localization in the nerve stimulator-guided blocks (median = 6) than in ultrasound-aided blocks (median = 2; P < .001). There were fewer blood vessel punctures with ultrasound-aided blocks (P = .03). CONCLUSIONS: During resident teaching, ultrasound-aided peripheral nerve-stimulated block required less time to perform than did nerve-stimulator-guided blocks. Fewer needle insertions were required to perform the ultrasound-guided blocks, and there were fewer blood vessel punctures when ultrasound was used.     

Magnetic resonance imaging of the distribution of local anesthetic during the three-in-one block

The three-in-one technique of simultaneously blocking the femoral, the lateral femoral cutaneous (LFC), and the obturator nerves by a single injection of a local anesthetic was first described in 1973, and it was suggested that the underlying mechanism was one of cephalad spread resulting in a blockade of the lumbar plexus. Today, the technique is widely used in surgery and pain management of the lower limb. Many investigators have, however, reported suboptimal analgesia levels, particularly in the obturator nerve. The purpose of this prospective study was to trace the distribution of a local anesthetic during a three-in-one block by means of magnetic resonance imaging (MRI). Seven patients scheduled for surgery of the lower limb were analyzed with the aid of a primary MRI and then received three-in-one blocks using 30 mL of bupivacaine 0.5% under the guidance of a nerve stimulator. A secondary MRI was performed to determine the distribution pattern of the local anesthetic. It emerged that the local anesthetic blocks the femoral nerve directly, the LFC nerve through lateral spread, and the anterior branch of the obturator nerve by slightly spreading in a medial direction. No involvement of the proximal and posterior portions of the obturator nerve was observed, nor was there any cephalad spread that could have resulted in a lumbar plexus blockade. We therefore conclude that the basis of the three-in-one block is confined to lateral, medial, and caudal spread of the local anesthetic, which effectively blocks the femoral and LFC nerves, as well as the distal anterior branch of the obturator nerve. IMPLICATIONS: We demonstrate by using magnetic resonance imaging that the mechanism of a three-in-one block is one of lateral, caudal, and slight medial spread of a local anesthetic with subsequent blockade of the femoral, the lateral femoral cutaneous, and the anterior branch of the obturator nerves. It does not involve cephalad spread of the local anesthetic with blockade of the lumbar plexus.     

Controlled obturator nerve block using electrostimulation: prevention of the stimulation of the obturator nerve during resection of the lateral walls of the bladder

An adductor contraction secondary to obturator nerve stimulation can occur during transurethral resection of a lateral bladder lesion and then can induce bladder perforation or hamper complete resection. Many technique have been advocated but they are ineffective or unreliable. Obturator nerve blockade in the obturator canal by local anesthesia with control by nerve stimulator can prevent these complications. The technique described, has been used in 12 patients it is reliable, fast and easy to perform.