Selective Obturator Research Articles

Ultrasound versus Nerve Stimulator Guided Obturator Nerve Block in Patients Undergoing Transurethral Resection of Bladder Tumor.

Urinary bladder cancer is more common in geriatric population. Transurethral resection of bladder tumor remains the mainstay of treatment. It is usually performed under subarachnoid block. However, obturator nerve is spared in subarachnoid block that can produce adductor jerk, which is associated with bladder injury, rupture, incomplete resection of tumor and hematoma. To overcome this jerk, selective obturator nerve block is commonly performed. Thus, we conducted this study to compare the efficacy of ultrasound and nerve stimulator-guided techniques for obturator nerve block. This is a prospective, comparative study conducted at a tertiary care hospital in Nepal. Sixty patients, scheduled to undergo Transurethral Resection of Bladder Tumor for lateral and posterolateral wall bladder cancer under subarachnoid block were enrolled and divided into two group having thirty patients in each groups. Group I received 15 ml of 0.25% Bupivacaine to block obturator nerve by using peripheral nerve stimulator. Group II received the same amount of Bupivacaine to block obturator nerve under ultrasound guidance. We evaluated the success of the block, ease of the procedure and complications. The adductor reflex was present in 23.33% of cases with nerve stimulator guided obturator nerve block, whereas, it was16.66% in ultrasound guided technique (p=0.75). The success rate of obturator nerve block was 76.66% in nerve stimulator guided technique, whereas 83.33% in ultrasound guided technique (p= 0.21). 83.33% of obturator nerve block was found to be easy in nerve stimulator guided technique, whereas 66.66 % in ultrasound guided technique (p = 0.14). There were no major complications noted. The findings of this study conclude that both ultrasound and nerve stimulator guided techniques equally abolished the adductor reflexes. Both techniques are easy to perform and safe.

Ultrasound Guided Versus Cystoscopy Guided Obturator Nerve Block (ONB) in Transurethral Resection of Bladder Tumours (TURBT): A Comparison of Haemodynamic Status of the Patients

Background: Selective obturator nerve block (ONB) is a current trend in transurethral resection of bladder tumour (TURBT), which is easy to administer, safe and prevents some major complications during operation. Objective: To compare the haemodynamic status of two groups of patients underwent two different techniques of obturator nerve block during TURBT operation – ultrasound guided ONB vs. cystoscopy guided ONB. Methods:This prospective, observational study was conducted in the Department of Anaesthesia, Analgesia, Palliative and Intensive Care Medicine, Dhaka Medical College Hospital, Dhaka, from September 2018 to August 2019. A total of 60 selected patients were randomly allocated into two groups: ultrasound guided ONB (group A) and cystoscopy guided ONB (group B) i.e., 30 in each group. Then heart rate and blood pressure were assessed at different point during and after surgery. Results: Mean age of the patients was 54.7±8.53 years. In total, 34(57%) cases were male and 26(43%) were female. Male to female ratio was 1.3:1. In group A, 19(63.3%) patients had ASA II status and 11(36.7%) had ASA III status, while in group B, the numbers were 18(60%) and 12(40%) respectively. There was no significant difference in demographics and ASA status between two groups (P>0.05). Average onset of obturator nerve block was faster in group A (8.17±1.4 min) than group B (11.3±2.68 min), (P<0.001). Mean heart rate at baseline, at the end of the operation and postoperative room were found 77.56±2.69 and 76.35±3.09, 77.16±1.59 and 75.67±2.21, 76.34±6.24 and 75.67±6.42 in group A and B respectively, while simultaneous recorded mean systolic blood pressure were 115.23±5.56 and 116.45±5.82, 118.73±1.63 and 118.54±1.72, 116.73±3.32 and 116.37±4.13 respectively and mean diastolic pressure were 78.82±1.67 and 79.87±2.98, 77.68±2.34 and 77.18±4.15, 73.63±1.15 and 73.53±2.28 respectively. However, the differences in haemodynamic status between two groups were not statistically significant(P>0.05). Conclusion: Our data suggest no difference between two techniques in terms of changes in haemodynamic status of the patients who underwent TURBT operation. Bangladesh Journal of Medical Science Vol. 22 No. 02 April’23 Page : 348-352

Outcomes of Ultrasound Guided Versus Cystoscopy Guided Obturator Nerve Block (Obn) In Transurethral Resection Of Bladder Tumour (Turbt)

Context: Selective obturator nerve block (ONB) limits obturator reflex, adductor contraction, and leg jerking in transurethral resection of bladder tumour (TURBT), which ultimately prevents complications such as bleeding, bladder perforation, or incomplete tumor resection. The present study aims to compare the effectiveness of two different techniques of obturator nerve block during TURBT. Methods: A prospective, observational study was conducted in the Department of Anaesthesia, Analgesia, Palliative and Intensive Care Medicine, Dhaka Medical College Hospital, Dhaka, Bangladesh, between September 2018 and August 2019 to evaluate the effectiveness of ultrasound guided ONB versus cystoscopy guided ONB in TURBT operation. A total of 60 selected patients were randomly allocated into two groups: ultrasound guided ONB (group A) and cystoscopy guided ONB (group B) i.e. 30 in each group. Then onset of anesthesia (nerve block), tumour removal and patient outcome were assessed at different point during and after surgery. Results: Mean age of the patients was 54.7±8.53 years. In total, 34(57%) cases were male and 26(43%) were female. Male to female ratio was 1.3:1. In group A, 19(63.3%) patients had ASA II status and 11(36.7%) had ASA III status, while in group B, the numbers were 18(60%) and 12(40%) respectively. There was no significant difference in demographics and ASA status between two groups (P>0.05). Average onset of obturator nerve block was faster in group A (8.17±1.4 min) than group B (11.3±2.68 min), (P<0.001). Total resectability of tumours were achieved in 28(93.3%) in group A and 23(76.6%) in group B during operation (P<0.001), while 2(22.22%) and 7(77.77%) tumours had incomplete removal respectively (P<0.05). Among complications, adductor jerks were evident in 2(6.7%) and 7(23.3%), bladder perforation in 1(3.3%) and 4(13.3%), and bleeding in 1(3.3%) and 3(10.0%) cases in group A and group B respectively. The differences were statistically significant ((P<0.05). Conclusion: Although both techniques are safe and easy to perform, ultrasound guided ONB results in faster onset of block and better resectability of tumour with less complication over cystoscopy guided ONB. J Dhaka Med Coll. 2021; 30(2) : 208-213

An Ultrasound-Guided Interfascial Injection Approach Versus an Ultrasound-Assisted Nerve Stimulating Approach of Obturator Nerve Block: A Randomized Clinical Trial.

BackgroundThe majority of bladder cancer patients are elderly and have various comorbidities, increasing the risk of complications following general anesthesia. Spinal anesthesia with a selective obturator nerve block (ONB) is an alternative to general anesthesia for transurethral resection of bladder tumor (TURBT); however, incomplete ONB can cause adductor muscle spasm. The objective of this study was to assess if the ultrasound-guided interfascial injection approach is compatible with the blind nerve stimulating technique for ONB in bladder cancers undergoing TURBT.MethodologyA total of 50 ONBs were performed for TURBTs under spinal anesthesia and were divided into two groups, that is, ONB with nerve stimulation control group (group RD1) and an experimental ultrasound-guided interfascial injection group (group RD2). During TURBT surgeries, one urology assistant determined obturator reflex grade (I-IV) at 15 minutes after injection completion in both groups.ResultsA success rate of 88% was achieved in group RD1 compared to 76% in group RD2, which was clinically significant. Three cases failed to achieve complete ONB in group RD1, and six cases in group RD2 failed to achieve complete ONB. One case in group RD1 and two cases in group RD2 exhibited grade II obturator re­flex during the surgery.ConclusionsUltrasound-guided interfascial injection approach was inferior to the ultrasound-guided nerve stimulating technique for ONB at the inguinal crease; hence, we recommend using both ultrasound and nerve stimulators for ONB.

Utilization of electromyography during selective obturator neurotomy to treat spastic cerebral palsy accompanied by scissors gait.

Selective obturator neurotomy is a commonly used neurosurgical intervention for spastic cerebral palsy with scissors gait. Here we report the use of surface electromyography to assess the accuracy and effect of selective obturator neurotomy procedures. Selective obturator neurotomy was carried out on 18 patients while using intraoperative electromyography. Contractions of adductor muscles were recorded by electromyography before and after neurotomy and assessed using root mean square and integrated electromyography tests. Passive and voluntary movements were recorded for all patients. Our results show that adductor spasms and adductive deformity of hip were improved in all patients with spastic cerebral palsy. Adductor muscle spatiality was improved significantly, confirmed by a significant decrease in the values of root mean square and integrated electromyography in both passive and voluntary movements after surgery. We show that electromyography is an effective tool for accurately and safely targeting nerve tracts during selective obturator neurotomy. Thus, we demonstrate a valuable noninvasive method to objectively evaluate the effect of treatment in spastic cerebral palsy patients.

Complications in Transurethral Resection of the Bladder Tumor: Using Nerve Stimulator with or Without Ultrasonography for Obturator Nerve Block: A Comparative Study

BackgroundThe use of ultrasonographic guide is a suggested way to ease the obturator nerve block procedure. Accordingly, in this study, the procedures by selective obturator nerve block with and without use of ultrasonographic guide were compared.MethodsThis interventional study was performed as an open-label randomized clinical trial among 50 consecutive subjects under surgery for intramural tumors of urinary bladder in a training hospital in 2016. The subjects were randomly assigned to be operated under spinal anesthesia accompanied with selective obturator nerve block (10 mL of 1.5% lidocaine adding 1:200000 epinephrine) with or without ultrasonographic guide. The outcomes were compared across the groups.ResultsThere was no statistically significant difference between the onset time in group without guide (6.3 ± 2.2 minutes) and that in the guided group (5.9 ± 2.1 minutes). The time required for the nerve block (4.4 ± 1.3 minutes versus 1.7 ± 0.8 minutes) was significantly shorter (P = 0.001). There were less complications in the group with use of ultrasonographic guide showing significant difference (P = 0.01). The success rate in block was significantly higher in the group with ultrasonographic guide (100% versus 92%, P > 0.05).ConclusionsFinally, according to the obtained results, it may be concluded that ultrasonography guidance would improve efficacy of obturator nerve block compared with conventional techniques.

A Selective Anterior Obturator Nerve Block for Total Hip Arthroplasty

A Selective Anterior Obturator Nerve Block for Total Hip Arthroplasty

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.

22: Paravascular Selective Approach Obturator Nerve Block to Counteract Thigh Adductor Spasm Induced During Transurethral Resection of Bladder Tumor

22: Paravascular Selective Approach Obturator Nerve Block to Counteract Thigh Adductor Spasm Induced During Transurethral Resection of Bladder Tumor

22. Paravascular Selective Approach Obturator Nerve Block to Counteract Thigh Adductor Spasm Induced During Transurethral Resection of Bladder Tumor

22. Paravascular Selective Approach Obturator Nerve Block to Counteract Thigh Adductor Spasm Induced During Transurethral Resection of Bladder Tumor

Paravascular Selective Approach Obturator Nerve Block to Counteract Thigh Adductor Spasm Induced During Transurethral Resection of Bladder Tumor

Paravascular Selective Approach Obturator Nerve Block to Counteract Thigh Adductor Spasm Induced During Transurethral Resection of Bladder Tumor

Late Presentation of Bleeding from a Traumatic Obturator Artery Aneurysm, Successfully Treated by Endovascular Means

Obturator artery bleeding is rare. During the acute phase of a severe pelvic trauma, massive bleeding can occur immediately. The pelvic fracture often leads to an arterial injury by the broken bone fragments. Our case was unusual due to the absence of any pelvic bone fracture and the late onset of an isolated groin haematoma. The duplex ultrasound and CT scan performed at the admission did not show any acute bleeding but a small groin haematoma. One month later the patient has a major haematoma secondary to an obturator artery pseudo-aneurysm. We successfully performed a selective obturator artery pseudo-aneurysm coil embolization.

Late Presentation of Bleeding from a Traumatic Obturator Artery Aneurysm, Successfully Treated by Endovascular Means

Obturator artery bleeding is rare. During the acute phase of a severe pelvic trauma, massive bleeding can occur immediately. The pelvic fracture often leads to an arterial injury by the broken bone fragments. Our case was unusual due to the absence of any pelvic bone fracture and the late onset of an isolated groin haematoma. The duplex ultrasound and CT scan performed at the admission did not show any acute bleeding but a small groin haematoma. One month later the patient has a major haematoma secondary to an obturator artery pseudo-aneurysm. We successfully performed a selective obturator artery pseudo-aneurysm coil embolization.

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.

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. 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.

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.

Evaluation of the cutaneous distribution following selective obturator nerve blockade

s and Programme: European Society of Anaesthesiologists; 9th Annual Meeting with the Swedish Society of Anaesthesiology; Gothenburg, Sweden, 7-10 April 2001: Local and Regional Anaesthesia

Combined Adductor-Gracilis Tenotomy and Selective Obturator-Nerve Resection for the Correction of Adduction Deformity of the Hip in Children with Cerebral Palsy

1. Combined adductor-gracilis tenotomy and selective obturator neurectomy is recommended as the procedure of choice in the correction of adduction deformities of the hips in cerebral spastic children. 2. This operation should be preceded by a careful analysis of the muscle potentialities about the hip joints and should be followed by early vigorous exercises for the activation and strengthening of the hip abductors. 3. In this operation the adductor longus, the adductor brevis, and the gracilis muscles are transected, and a selective obturator neurectomy is performed. 4. This procedure has been completed on thirty-eight patients during the past eight years. Improvement was noted in thirty-five of these patients.