Comparison of the success rate of inguinal approach with classical pubic approach for obturator nerve block in patients undergoing TURB

Comparison of Ultrasound Versus Ultrasound With Nerve Stimulation-Guided Obturator Nerve Block to Prevent Adductor Spasm in Patients Undergoing Transurethral Resection of Bladder Tumor: A Randomized Controlled Study

Background This study aimed to compare ultrasound versus ultrasound with nerve stimulation-guided obturator nerve block (ONB) for the prevention of adductor spasm in patients undergoing transurethral resection of bladder tumor (TURBT). Methodology This randomized controlled study included 240 adult patients in the age group of 30 to 70 years undergoing TURBT for lateral and posterolateral wall bladder tumors who fulfilled the American Society of Anesthesiologists grade I and II criteria. The patients were divided into two groups: group U (n = 120) included patients who underwent ONB using an ultrasound-guided technique and group UN (n = 120) included patients who underwent ONB using ultrasound with the nerve stimulation technique. Block performance time, adductor jerks/spasms, adductor muscle power, and patient and surgeon satisfaction were compared. A P-value <0.05 was considered statistically significant. Results The mean block performance time in group U was significantly less (4.4 ± 0.82 minutes) than in group UN (6.55 ± 0.37 minutes). Compared to group U, group UN had significantly fewer adductor jerks/spasms during the surgery (7.76% vs. 20.35%, p = 0.006), significantly more surgeon satisfaction (92.24% vs. 79.65%, p = 0.006), significantly more patient satisfaction (92.24% vs. 79.65%, p = 0.006), and comparable complications (excessive bleeding and minor bladder injury) and adductor muscle power after the block (p > 0.05). Conclusions ONB using the nerve stimulation technique under ultrasound guidance has a longer mean block performance time, a higher success rate, and higher surgeon satisfaction than ONB under ultrasound guidance only.

Comparison of different methods of obturator nerve block in transurethral resection of bladder tumors: A systematic review and network meta-analysis

BACKGROUND

Bladder cancer is the most common malignancy of the urinary system, and accounts for 3% of newly diagnosed tumors. Transurethral resection of bladder tumor plays a key role in treating bladder cancer, among which one of the most serious complications is bladder perforation caused by obturator nerve reflex. Obturator nerve reflex can be prevented by inducing obturator nerve block after lumbar anesthesia. However, No study so far has compared the inhibitory effect of different obturator nerve block approaches on intraoperative obturator nerve reflex and bladder perforation.

METHOD

In this study, we conducted a network meta-analysis (NMA) of studies comparing the efficacy of different obturator nerve block approaches performed after lumbar anesthesia in operation.

RESULT

The distal obturator nerve block guided by peripheral nerve stimulator is the best approach for preventing obturator reflex. The proximal obturator nerve block guided by ultrasound is the best approach for preventing bladder perforation.

CONCLUSION

Spinal anesthesia combined with the distal obturator nerve block guided by peripheral nerve stimulator is the most optimal approach to prevent the obturator nerve reflex. But the doctor should choose the appropriate anesthesia method according to the patient's general condition, tumor location, and doctor's proficiency in puncture techniques.

Is Obturator Nerve Block Effective as Spinal Anesthesia in Preventing Adductor Spasms in General Anesthesia Without Muscle Relaxants?

Aim: During transurethral resection of bladder tumor (TUR-BT), adductor muscle spasms in varying degrees can be seen due to stimulation of obturator nerve if the tumor is in the inferolateral localization. This can cause some serious complications such as bladder perforation. We aim to show the effectiveness of obturator nerve block (ONB) to avoid the adductor muscle spasm in general anesthesia applied with laryngeal mask (LMA) without using muscle relaxant according to the spinal anesthesia method.

Methods: The study has been designed prospectively and observationally. A total of 64 patients who underwent TUR-BT were divided into two groups. Group I consisted of 30 patients in whom TUR-BT was performed under general anesthesia without muscle relaxant + ONB. Group II consisted of 31 patients in whom TUR-BT was performed under spinal anesthesia + ONB. Intraoperative adductor spasm, the severity of adductor response, and surgeon satisfaction were recorded.

Results: Median values of adductor muscle strengths were found to be higher in Group I (p < 0.05). There was no statistically significant relationship between the anesthetic method and adductor spasm (p = 0.110). Of patients in Group I, 13.4% showed moderate or severe adductor response, whereas the ratio was 0% in Group II (p = 0.015). Surgeon satisfaction was similar in both groups (p = 0.363).

Conclusions: Obturator spasm was not different in both anesthesia techniques. General anesthesia without muscle relaxant combined with ONB was found effective to prevent adductor muscle spasms as the spinal anesthesia in TUR-BT operations. It has been concluded that surgical complications can be reduced via general anesthesia without the muscle relaxant method, although surgeons' satisfaction did not alter. General anesthesia and obturator block applications with the help of LMA without muscle relaxants can be preferred in short-term TUR-B operations where spinal anesthesia is not desired.

Anesthetic considerations for urologic surgeries

Urologic surgeries are widely performed, and the cases have increased owing to the fact that the elderly population is growing. The narrow and limited surgical space is a challenge in performing most urologic surgeries. Additionally, the elderly population is exposed to the risk of perioperative complications; therefore, a comprehensive understanding and approach are required to provide optimized anesthesia during surgery. We have searched the literature on anesthesia for urologic surgeries and summarized the anesthetic considerations for urologic surgeries.

[Optimizing the management of bladder cancer in older patients]

AIM

To define and present potential improvements for the management of bladder cancer in older patients.

METHOD

Bibliographical search was performed from the Medline bibliographic database (NLM Pubmed tool) and Embase focused on: bladder cancer, treatment, BCG, chemotherapy, cystectomy, and elderly.

RESULTS

The oncological principles of medico-surgical management of bladder cancer do not differ according to age. On the other hand, the patient comorbidities have been likely to alter the tolerance of these treatments. At the NMIBC stages, no adaptation of the standard treatment has demonstrated any interest. At the MIBC stages, the prognosis was improved by geriatric multidisciplinary perioperative management.

CONCLUSION

The indications and principles of surgical treatments must be identical regardless of the patient age. At the NMIBC stages, adjuvant therapy, including BCG therapy, should not be questioned because of the age of the patient. On the other hand, at the localized MIBC stages, neoadjuvant and adjuvant chemotherapy should not be considered as a standard and their indications assessed individually after geriatric assessment.

Classic versus Inguinal Approach for Obturator Nerve Block in Transurethral Resection of Bladder Cancer under Spinal Anesthesia: A Randomized Controlled Trial

Single spinal anesthesia in transurethral resection of bladder tumor (TURBT) has been reported to be unable to prevent obturator nerve stimulation and adductor muscle contraction, which can cause complications like bladder perforation. The present study aimed to compare the effectiveness of the classic and inguinal approaches for obturator nerve block (ONB ). Seventy patients with cancers of the lateral wall of the bladder, scheduled to undergo TURBT at Imam Reza Hospital (Tabriz, Iran) during a 6-month period as of June 2016, were randomly allocated to groups of inguinal and classic methods (n=35). After the infusion of 500 mL of normal saline, spinal anesthesia was commenced using 3 mL (15 mg) of bupivacaine. Then ONB was performed using 10 mL of 1% lidocaine via the inguinal or classic approach in the inguinal group or the classic group, respectively. The success rate, defined as lack of post-block contraction with stimulation or during surgery, number of puncture attempts, time of block onset, and patient and surgeon satisfaction, was compared between the 2 methods using SPSS, version 19. The success rate of ONB was significantly higher in the inguinal group (97.1% vs. 71.4%; P=0.003). The number of puncture attempts in the classic group was more than that in the inguinal group (3.71±1.10 vs. 1.66±0.68, respectively; P<0.001). The block onset time was shorter in the inguinal group (1.5±0.66 min vs. 2.9±1.18 min; P<0.001). Dissatisfaction of the patient (19 cases vs. 2 cases) and the surgeon (10 cases vs. no case) was higher in the classic group (P<0.001). Compared to the classic approach, the inguinal approach for ONB appeared to be an easily performable, effective block with a high success rate, rapid onset, and good patient and surgeon satisfaction.

TRIAL REGISTRATION NUMBER

IRCT 201608171772N21.

Effectiveness of spinal anesthesia combined with obturator nerve blockade in preventing adductor muscle contraction during transurethral resection of bladder tumor

Objective

To determine whether spinal anesthesia combined with obturator nerve blockade (SOB) is effective in preventing obturator nerve stimulation, jerking and bladder perforation during transurethral resection of bladder tumor (TURBT).

Material and methods

In this clinical trial, 30 patients were randomly divided into two groups: spinal anesthesia (SA) and SOB. In SA group, 2.5 cc of 0.5% bupivacaine was injected intrathecally using a 25-gauge spinal needle and in SOB after spinal anesthesia, a classic obturator nerve blockade was performed by using nerve stimulation technique.

Results

There was a statistically significant difference between jerking in both groups (p=0.006). During the TURBT, surgeon satisfaction was significantly higher in SOB group compared to SA group (p=0.006). There was no significant correlation between sex, patient age and location of bladder tumor between the groups (p>0.05).

Conclusion

Obturator nerve blockade by using 15 cc lidocaine 1% is effective in preventing adductor muscle spasms during TURBT.

Ultrasound-Guided Obturator Nerve Block: A Focused Review on Anatomy and Updated Techniques

This review outlines the anatomy of the obturator nerve and the indications for obturator nerve block (ONB). Ultrasound-guided ONB techniques and unresolved issues regarding these procedures are also discussed. An ONB is performed to prevent thigh adductor jerk during transurethral resection of bladder tumor, provide analgesia for knee surgery, treat hip pain, and improve persistent hip adductor spasticity. Various ultrasound-guided ONB techniques can be used and can be classified according to whether the approach is distal or proximal. In the distal approach, a transducer is placed at the inguinal crease; the anterior and posterior branches of the nerve are then blocked by two injections of local anesthetic directed toward the interfascial planes where each branch lies. The proximal approach comprises a single injection of local anesthetic into the interfascial plane between the pectineus and obturator externus muscles. Several proximal approaches involving different patient and transducer positions are reported. The proximal approach may be superior for reducing the dose of local anesthetic and providing successful blockade of the obturator nerve, including the hip articular branch, when compared with the distal approach. This hypothesis and any differences between the proximal ONB techniques need to be explored in future studies.

Perineural Dexmedetomidine as an Adjuvant Reduces the Median Effective Concentration of Lidocaine for Obturator Nerve Blocking: A Double-Blinded Randomized Controlled Trial

Research suggests that the addition of dexmedetomidine to local anesthetics can prolong peripheral nerve blocks; however, it is not known whether dexmedetomidine can reduce the quantity of local anesthetic needed. We hypothesized that adding dexmedetomidine as an adjuvant to an obturator nerve block could reduce the median effective concentration of lidocaine. In this double-blinded randomized trial, 60 patients scheduled for elective transurethral resection of bladder tumors on the lateral wall were randomly divided into two groups: the control group (C group, n = 30) and the dexmedetomidine group (D group, n = 30). Two main branches of the obturator nerve (i.e., anterior and posterior) were identified using neural stimulation at the inguinal level, with only lidocaine used for the C group and 1 μg/kg dexmedetomidine combined with lidocaine used for the D group. The median effective concentration was determined by an up-and-down sequential trial. The ratio of two consecutive concentrations was 1.2. The median effective concentration (95% confidence interval) of lidocaine was 0.57% (0.54%-0.62%) in the C group and 0.29% (0.28%-0.38%) in the D group. The median effective concentration of lidocaine was significantly lower in the D group than in the C group (p < 0.05). These results indicate that dexmedetomidine (1 μg/kg) in combination with lidocaine for obturator nerve block decreases the median effective concentration of lidocaine.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02066727.

Impact of nerve stimulator-guided obturator nerve block on the short-term outcomes and complications of transurethral resection of bladder tumour: A prospective randomized controlled study

INTRODUCTION

In this prospective randomized controlled study, we investigated the efficacy of obturator nerve block (ONB) on adductor muscle spasm and related short-term outcomes and complications in patients who underwent transurethral resection of lateral wall-located bladder tumours (TURBT).

METHODS

Between July 2014 and February 2015, 70 patients scheduled to undergo TUR of lateral bladder wall tumours were enrolled in the study. All patients were preoperatively evaluated by cystoscopy and imaging tools and selected according to localized tumours on the lateral bladder wall. Patients were randomly allocated to Group SA (35 patients who underwent only spinal anesthesia) and Group ONB (35 patients who underwent spinal anesthesia combined with ONB by the nerve stimulator). An independent observer, blinded to the approach, evaluated the obturator signs, including adductor muscle contraction, bladder perforation, and completeness of the resection during the TURBT procedure.

RESULTS

The differences between groups regarding mean operation time, tumour size, and number were not statistically significant (p > 0.05). Adductor muscle contraction was detected in 40% of patients in Group SA and 11.4% in Group ONB. This difference was statistically significant (p = 0.021). Complete bladder perforation was detected in 2 patients in Group SA, whereas no perforation was observed in Group ONB. There was no case of severe bleeding in both groups.

CONCLUSIONS

We found that ONB performed after spinal anesthesia was effective in preventing intraoperative complications due to adductor muscle spasm while performing TURBT. Our study limitations include its small sample size, since we only enrolled patients with primary lateral wall-localized bladder tumour. Also, we excluded patients who underwent bipolar TURBT.

Comparison of inguinal versus classic approach for obturator nerve block in patients undergoing transurethral resection of bladder tumors under spinal anesthesia

BACKGROUND

Selective obturator nerve blockade (ONB) is an effective option to prevent adductor spasm during transurethral resection of bladder tumors (TURBT) involving the lateral wall under spinal anesthesia (SA). The classic approach is less popular as the obturator nerve is deep seated and associated with vascular injury. The inguinal approach was described as a safer alternative. This randomized clinical study was undertaken to compare the ease of block, the success rate and complications of the classic pubic and superficial inguinal approach for ONB.

MATERIALS AND METHODS

A total of 30 patients scheduled to undergo TURBT under SA were administered bilateral ONB. Inguinal approach recently described by Choquet was performed on one side and classic approach described by Labat was performed on the other side in random order using a nerve stimulator. The ease of block, success rate (number of attempts to accomplish the block) and complications were noted and compared between both the approaches. Chi-square analysis was performed to compare the ease of approach of the two techniques. Non-parametric analyses using Mann Whitney test was used to compare the number of attempts to accomplish the block in each approach. A value of P < 0.05 was considered statistically significant.

RESULTS

The ease of block (P = 0.09) and the median number of attempts to accomplish the block (P = 0.45) were comparable between the two approaches. The incidence of vascular injury was higher in classic approach (P = 0.056).

CONCLUSIONS

Inguinal approach is a useful alternative to classic approach block for patients undergoing TURBT under SA.

[Anesthesia in endourological and robot-assisted interventions]

The improved drug therapy leads to increasingly older patients with complex comorbidities in the discipline of operative urology. Today, improved technical equipment provides new operational capabilities in the field of urology. The prone and lithotomy position during surgery leads to physiological changes that affect anesthesia management. The surgical risk of procedures such as transurethral surgery of the prostate or bladder is being altered by laser surgery and other new technologies. Although the incidence of transurethral resection (TUR) syndrome has been reduced in recent years, the intrusion of irrigation fluid still has to be considered during anesthesia. Robot-assisted surgery has successfully completed the experimental stage and is widely used so that new targets have to be challenged. Ureterorenoscopy is performed with flexible, small caliber ureteroscopes which even allow treatment of renal calculi under analgosedation within short time periods. Percutaneous nephrostomy and litholapaxy are still frequently performed in the prone position. With respect to the risks arising from patient positioning, supine or lateral positioning should be considered in individual cases. A good communication between the surgeon and anesthetist allows deviation from daily routine procedures if special indications require a modified approach. In conclusion, a profound knowledge of the (patho-)physiology of general anesthesia and endourological diseases enables anesthetists to provide a prospective type anesthesia, which should prevent the occurrence of life-threatening incidents.