A new inguinal approach for the obturator nerve block: anatomical and randomized clinical studies

BACKGROUND: Obturator nerve block is highly recommended for knee surgery in addition to a femoral nerve block. The main disadvantage of the classic approach at the pubic tubercle is low patient acceptance due to pain and discomfort. The authors hypothesized that the use of a new inguinal obturator nerve block technique would reduce pain and discomfort in patients. METHODS: The inguinal approach was simulated in five fresh cadavers. Injection of latex was performed in two cadavers. The location of the needle and the extent of latex solution were analyzed. Fifty patients scheduled to undergo arthroscopic knee surgery were randomly assigned to receive obturator nerve block using either the inguinal (n = 25) or the pubic tubercle approach (n = 25). RESULTS: In all cadavers, the needle was close to the obturator nerve branches, which were surrounded by the latex solution. In the clinical study, visual analog scale pain scores and discomfort of block placement were significantly lower in the inguinal group compared with the pubic tubercle group (P < 0.01). In the inguinal group, there was a significant decrease in block performance time (P < 0.05) and in bolus of propofol and fentanyl used for the procedure (P < 0.01). Twenty minutes after application of the block, adductor strength decrease, occurrence, and location of cutaneous distribution of the obturator nerve were not significantly different between the groups. The incidence of minor complications was significantly increased in the pubic tubercle group (P < 0.05). No major complications were observed. CONCLUSIONS: The new inguinal approach decreases patient discomfort and pain of block placement as well as the time and sedation and analgesics required for a similar quality of sensory and motor block compared with the pubic tubercle approach.     

Pubic tubercle side approach to the obturator nerve block

BACKGROUND: The authors describe the pubic tubercle side approach of the obturator nerve block for the management of adductor muscle constriction associated with the transurethral resection of the lateral wall bladder tumor. METHODS: The pubic tubercle side approach of the obturator nerve block was performed by a inserting needle at the midpoint of the femoral artery and the pubic tubercle. After the needle encountered the superior ramus of pubis, the needle was redirected vertical or slightly caudal, passeing the vicinity of the inferior margin of the superior ramus of pubis, and then advanced to the trunk of the obturator nerve. The obturator nerve was identified by its response to nerve stimulation. The pubic tubercle side approach using more than 5 ml of 1.0% lidocaine was performed by a single injection until there was no response to nerve stimulation. On the other hand, by the traditional approach to the obturator nerve block, after the initial local anesthetic injection the needle was redirected lateral and slightly caudal. If the response to nerve stimulation was still elicited, more local anesthetic was administered. RESULTS: Evaluation of the efficacy of the pubic tubercle side approach was performed in-terms of quantity of the local anesthetic used and the success rate. In comparison with the traditional approach, a smaller dose of local anesthetic was used in spite of the higher success rate. CONCLUSIONS: The pubic tubercle side approach of the obturator nerve was useful and without complications in comparison with the traditional approach.     

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.     

Adding a selective obturator nerve block to the parasacral sciatic nerve block: an evaluation

Our aim was to objectively evaluate the efficacy of obturator nerve anesthesia after a parasacral block. Patients scheduled for knee surgery had a baseline adductor strength evaluation. After a parasacral block with 30 mL 0.75% ropivacaine, sensory deficit in the sciatic distribution (temperature discrimination) and adductor strength were assessed at 5-min intervals. Patients with an incomplete sensory block (defined as a temperature discrimination score of less than 2 in the 3 cutaneous distributions of the sciatic nerve tested) 30 min after the parasacral block were excluded from the study. Subsequently, a selective obturator block was performed with 7 mL 0.75% ropivacaine and adductor strength was reassessed at 5 min intervals for 15 min. Finally, a femoral block was performed using 10 mL 0.75% ropivacaine. Patient discomfort level during each block was assessed using a visual analog scale (VAS). Thirty-one patients completed the study. Five patients were excluded as a result of inadequate sensory block in the sciatic distribution 30 min after the parasacral block (success rate of 89%). Thirty min after the parasacral block, adductor strength decreased by 11.3% +/- 7% compared with baseline (85 +/- 24 versus 97 +/- 28 mm Hg, P = 0.002). Fifteen min after the obturator nerve block, adductor muscle strength decreased by an additional 69% +/- 7% (16.6 +/- 15 versus 85 +/- 24 mm Hg, P < 0.0001). VAS scores were similar for all blocks (26 +/- 19, 28 +/- 24, and 27 +/- 19 mm for parasacral, obturator, and femoral respectively). Four parasacral blocks were simulated in 2 fresh cadavers using 30 mL of colored latex solution. The spread of the die in relation to the obturator nerve was assessed. Injection of 30 mL colored latex into cadavers resulted in spread of the injectate restricted to the sacral plexus. These findings demonstrate the unreliability of parasacral block to achieve anesthesia of the obturator nerve. A selective obturator block should be considered in the clinical setting when this is desirable.     

Interadductor approach to obturator nerve block for transurethral resection procedure: comparison with traditional approach

Purpose. We compared the interadductor approach of obturator nerve block with the traditional approach in terms of the insertion-adductor contraction interval (ICI), success rate, completion of the block, and plasma lidocaine concentration. Methods. An obturator nerve block by the interadductor approach was performed by needle insertion 1 cm behind the adductor longus tendon and 2 cm lateral to the pubic arch in 12 patients, and by the traditional approach in 12 patients. Results. The ICI with the interadductor approach was significantly shorter than that with the traditional approach. The success rate, completion of the block, and plasma lidocaine concentrations were similar with both approaches. Conclusion. The interadductor approach can provide faster identification of the obturator nerve than the traditional approach. Received: January 29, 2001 / Accepted: December 12, 2001     

A new ultrasound‐guided pubic approach for proximal obturator nerve block: clinical study and cadaver evaluation

We evaluated an alternative technique for ultrasound‐guided proximal level obturator nerve block that might facilitate needle visualisation using in‐plane ultrasound guidance. Twenty patients undergoing transurethral bladder tumour resection requiring an obturator nerve block were enrolled into a prospective observational study. With the patient in the lithotomy position, the transducer was placed on the medial thigh along the extended line of the inguinal crease, and aimed cephalad to view a thick fascia between the pectineus and obturator externus muscles that contains the obturator nerve. A stimulating nerve block needle was inserted at the pubic region and advanced in‐plane with the transducer in an anterior‐to‐posterior direction. Eight ml levobupivacaine 0.75% was injected within the fascia. The median (IQR [range]) duration for ultrasound identification of the target and injection were 8.5 (7–12 [5–24]) s and 62 (44.5–78.25 [39–383]) s, respectively. All blocks were successful. A cadaver evaluation demonstrated that the dye injected into the target fascia using our technique travelled retrogradely through the obturator canal, and surrounded the anterior and posterior branches of the obturator nerve both proximally and distally to the obturator canal. We believe that this is a promising new technique for ultrasound‐guided proximal level obturator nerve block.     

Comparison of 4 techniques for internal saphenous nerve block

OBJECTIVE: To assess the efficacy of 4 techniques for internal saphenous nerve block with 10 mL of 1.5% mepivacaine. METHODS: Eighty ASA I-II patients scheduled for foot (hallux valgus) surgery with combined sciatic and saphenous nerve blocks were randomized to receive the saphenous nerve block by one of the following techniques: a paravenous approach (n = 20), a transsartorial approach (n = 20), a femoral nerve approach in the inguinal region using a nerve stimulator (n = 20), and by subcutaneous infiltration between the tibial tuberosity and the internal gastrocnemius muscle (n = 20). A pressure cuff was placed 10 cm below the knee of all patients. Success was assessed by pin prick inside the ankle 30 minutes after initiation of the block. Tolerance of the pressure cuff and discomfort during performance of the technique were also assessed. RESULTS: The 4 groups were similar as to distribution of males and females and mean weight, age, and height. Blocking the saphenous nerve by way of the femoral nerve in the inguinal region was the most effective approach (success in 95% of patients), significantly better than the other 3 techniques (P < 0.05). The paravenous approach was successful in 60% of cases, the transsartorial approach in 50%, and the subcutaneous infiltration technique in 45%. The pressure cuff was well tolerated by all patients (100%) in whom the femoral nerve approach was used. The cuff was tolerated by 70% in the paravenous approach group, by 65% in the transsartorial approach group, and by 60% in the subcutaneous infiltration group. Patients reported more discomfort during initiation of the blockade in the paravenous approach and subcutaneous infiltration groups than in the femoral nerve or transsartorial approach groups (P < 0.05). CONCLUSION: The femoral nerve approach in the inguinal region, with nerve stimulator, to block the internal saphenous nerve led to a larger number of successful blocks than did the paravenous or transsartorial approaches, or the technique of subcutaneous infiltration between the tibial tuberosity and internal gastrocnemius muscle.     

A new anterior approach to the sciatic nerve block

BACKGROUND: Although several anterior approaches to sciatic nerve block have been described, they are used infrequently. The authors describe a new anterior approach that allows access to the sciatic nerve with the patient in the supine position. METHOD: Sciatic nerve blocks were performed in 22 patients. A line was drawn between the inferior border of the anterosuperior iliac spine and the superior angle of the pubic symphysis tubercle. Next, a perpendicular line bisecting the initial line was drawn and extended 8 cm caudad. The needle was inserted perpendicularly to the skin, and the sciatic nerve was identified at a depth of 10.5 cm (9.5-13.5 cm; median and range) using a nerve stimulator and a 15-cm b-beveled insulated needle. After appropriate localization, either 30 ml mepivacaine, 1.5% (group 1 = knee arthroscopy; n = 16), or 15 ml mepivacaine, 1.5%, plus 15 ml ropivacaine, 0.75%, (group 2 = other procedures; n = 6) was injected. RESULTS: Appropriate landmarks were determined within 1.3 min (0.5-2.0 min). The sciatic nerve was identified in all patients within 2.5 min (1.2-5 min), starting from the beginning of the appropriate landmark determination to the stimulation of its common peroneal nerve component in 13 cases and its tibial nerve component in 9 cases. A complete sensory block in the distribution of both the common peroneal nerve component and the tibial nerve component was obtained within 15 min (5-30 min). A shorter onset was observed in patients who received mepivacaine alone compared with those who received a mixture of mepivacaine plus ropivacaine (10 min [5-25 min] vs. 20 min [10-30 min]; P < 0.05). Recovery time was 4.6 h (2.5-5.5 h) after mepivacaine administration. The addition of ropivacaine produced a block of a much longer duration 13.8 h (5.2-23.6 h); P < 0.05. No complications were observed. CONCLUSIONS: This approach represents an easy and reliable anterior technique for performing sciatic nerve blocks.     

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。     

The paravertebral nerve root block for inguinal herniorrhaphy—A comparison with the field block approach

Background and Objectives. Our objective was to evaluate the efficacy of the paravertebral block for inguinal herniorrhaphy by comparison with the well-established field block. Methods. Thirty patients undergoing inguinal herniorrhaphy were randomly divided into two groups. Group A (n = 15) received paravertebral block of the ipsilateral nerve roots of T12, L1, and L2. Group B (n = 15) received field block. Each block was evaluated in terms of the degree of patient discomfort associated with surgical manipulations, requirement for supplemental anesthetic, the degree of patient discomfort associated with block performance, and the overall degree of patient satisfaction. Results. Both approaches were successful in blocking somatic sensory fibers. The paravertebral approach showed a significantly higher success rate than the field block (P < .01), regarding frequency of pain relative to surgical manipulation of the spermatic cord, hernial sac, and also in terms of need to supplement the surgery with local anesthetic (P < .01). The paravertebral block required significantly less local anesthetic and less needle insertions than the field block. Conclusions. The paravertebral nerve root block proved to be superior to the field block, to be devoid of side effects, and was acceptable to the patients.     

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.     

The parasacral sciatic nerve block does not induce anesthesia of the obturator nerve

Purpose

The ability of the parasacral sciatic nerve block (PSNB) to induce anesthesia of the obturator nerve remains controversial. Our objective was to evaluate the anesthesia of the obturator nerve after a PSNB.

Methods

Forty patients scheduled to undergo knee surgery (anterior cruciate ligament reconstruction) were included in this prospective, randomized, controlled study. Patients were randomized to receive PSNB alone (control group, n = 20) or PSNB in combination with an obturator nerve block (obturator group, n = 20). After evaluation for 30 min, the two groups received a femoral nerve block, and patients were taken to surgery. The obturator nerve blockade was assessed by measurement of adductor strength at baseline (T0) and every 10 min during the 30-min evaluation (T10, T20, and T30). Pain scores after tourniquet inflation and during surgery were compared between the two groups. The requirement for additional intravenous analgesia and/or sedation was also recorded.

Results

The two groups had comparable demographic and surgical characteristics. Four patients were excluded from the study because of PSNB or femoral nerve block failure. The adductor strength values were similar between groups at T0 but were significantly lower in the obturator group at T10, T20, and T30 (p < 0.0001). Patients in the obturator group reported less pain than those in the control group (p < 0.05). They also required less additional intravenous sedation and/or analgesia (p < 0.05).

Conclusion

This clinical study demonstrated that the PSNB is an unreliable means of inducing anesthesia of the obturator nerve and emphasizes the need to block this nerve separately to induce adequate analgesia during knee surgery.     

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.     

The anterior combined approach via a single skin injection site allows lower limb anesthesia in supine patients

PURPOSE: Lower limb anesthesia (LLA) requires the combination of, at least, three-in-one and sciatic nerve (SCN) blocks. Anterior approaches are easier to perform with minimal discomfort in supine patients, specially for traumatology. Feasibility of a single needle entry combined approach is reported. CLINICAL FEATURES: The combined landmark was applied in 119 ASA I and II patients (32-68 yr) scheduled for surgery below the knee. Needle (nerve stimulation applied through a single 150-mm long b-bevelled insulated needle) was inserted at the midpoint between the two classical approaches. Thirty and 15 mL of 0.5% ropivacaine were injected close to the femoral and the SCN, respectively. During the following 45 min, the extent of sensory block and knee and ankle motor block were assessed. Landmarks were determined within 1.7 min (0.7-2.2 min). The entire procedure was performed within 4.2 min (2.9-7.1 min) from the determination of the landmark to the SCN infiltration. The three-in-one technique was successful in 89.9% while SCN was successful in 94.9%. Femoral and tibial nerves were always blocked. Blockade of the posterior cutaneous femoral nerve was observed in 78% of patients. The extent and the quality of the sensory block always allowed surgery. Additional iv sedation was needed in 32.6% of patients. Motor block (adapted Bromage's scale > 2) was observed in the femoral (98.3%), the obturator (84.8%), the tibial (97.4%) and the common peroneal (85.7%) nerve distributions. No important adverse effects were recorded. CONCLUSION: The anterior combined approach via a single needle entry represents a technically easy and reliable technique to perform LLA in the supine patient.     

Ilioinguinal Nerve Entrapment after Tension-free Vaginal Tape (TVT) Procedure

The anatomy of the ilioinguinal nerve makes it vulnerable to entrapment near its exit from the superficial inguinal ring, where it lies almost directly superior to the pubic tubercle. Ilioinguinal nerve entrapment is a documented complication of inguinal herniorrhaphy, inguinal lymph node dissection, appendectomy, Pfannenstiel incision and the needle suspension procedure. It has not previously been described as a complication of the tension-free vaginal tape (TVT) procedure, which is the most recent technique for the treatment of genuine urinary stress incontinence. This paper describes a clinical history to illustrate the diagnosis and management of ilioinguinal nerve entrapment occuring as a complication of tension-free vaginal tape procedure.     

Bone fixation technique for transvaginal needle suspension

The transvaginal needle suspension procedure coupled with the bone fixation technique provides excellent restoration of continence without causing outflow obstruction. The surgical procedure is precise, with a significant decrease in postoperative pain and discomfort when the pubic tubercle is utilized as the fixation point for the suspension sutures.     

Postoperative analgesia after total knee replacement: the effect of an obturator nerve block added to the femoral 3-in-1 nerve block

Femoral nerve block (FNB) does not consistently produce anesthesia of the obturator nerve. In this single-blind, randomized, controlled study we added a selective obturator nerve block (ONB) to FNB to analyze its influence on postoperative analgesia after total knee replacement (TKR). Before general anesthesia, 90 patients undergoing TKR received FNB (Group 1), FNB and selective ONB (Group 2), or placebo FNB (Group 3). Postoperative analgesia was further provided by morphine IV via patient-controlled analgesia. Analgesic efficacy and side effects were recorded in the first 6 h after surgery. Adductor strength decreased by 18% +/- 9% in Group 1 and by 78% +/- 22% in Group 2 (P < 0.0001). Total morphine consumption was reduced in Group 2 compared with Groups 1 and 3 (P < or = 0.0001). Patients in Group 2 reported lower pain scores than those in Groups 1 and 3 (P = 0.0003). The incidence of nausea was more frequent in Groups 1 and 3 (P = 0.01). We conclude that FNB does not produce complete anesthesia of the obturator nerve. Single-shot FNB does not provide additional benefits on pain at rest over opioids alone in the early postoperative period. The addition of an ONB to FNB improves postoperative analgesia after TKR.     

A New Anterior Approach to the Sciatic Nerve Block

Background: Although several anterior approaches to sciatic nerve block have been described, they are used infrequently. The authors describe a new anterior approach that allows access to the sciatic nerve with the patient in the supine position.

Method: Sciatic nerve blocks were performed in 22 patients. A line was drawn between the inferior border of the anterosuperior iliac spine and the superior angle of the pubic symphysis tubercle. Next, a perpendicular line bisecting the initial line was drawn and extended 8 cm caudad. The needle was inserted perpendicularly to the skin, and the sciatic nerve was identified at a depth of 10.5 cm (9.5-13.5 cm; median and range) using a nerve stimulator and a 15-cm b-beveled insulated needle. After appropriate localization, either 30 ml mepivacaine, 1.5% (group 1 = knee arthroscopy; n = 16), or 15 ml mepivacaine, 1.5%, plus 15 ml ropivacaine, 0.75%, (group 2 = other procedures; n = 6) was injected.

Results: Appropriate landmarks were determined within 1.3 min (0.5-2.0 min). The sciatic nerve was identified in all patients within 2.5 min (1.2-5 min), starting from the beginning of the appropriate landmark determination to the stimulation of its common peroneal nerve component in 13 cases and its tibial nerve component in 9 cases. A complete sensory block in the distribution of both the common peroneal nerve component and the tibial nerve component was obtained within 15 min (5-30 min). A shorter onset was observed in patients who received mepivacaine alone compared with those who received a mixture of mepivacaine plus ropivacaine (10 min [5-25 min]vs. 20 min [10-30 min];P< 0.05). Recovery time was 4.6 h (2.5-5.5 h) after mepivacaine administration. The addition of ropivacaine produced a block of a much longer duration 13.8 h (5.2-23.6 h);P< 0.05. No complications were observed.     

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。