A Comparison of Precision and Safety using Three Recognized Ultrasound-Guided Approaches to Cervical Medial Branch Blocks: A Cadaver Study.

BACKGROUND: Ultrasound (US) guidance is widely used for needle positioning for cervical medial branch blocks (CMBB) and radiofrequency ablation, however, limited research is available comparing different approaches. OBJECTIVE: We aimed to assess the accuracy and safety of 3 different US-guided approaches for CMBB. STUDY DESIGN: A cadaveric study divided into ultrasound-guided needle placement and fluoroscopy evaluation stages. SETTING: Department of Pathology, Forensic, and Insurance Medicine, Semmelweis University. METHODS: Sonographically guided third occipital nerve (TON), C3, C4, C5 and C6 medial branch injections and radiology evaluations were performed.The 3 approaches compared were:1. ES (published by Eichenberger-Siegenthaler): US probe in the coronal plane to visualize the cervical articular pillars, needle approach out of the plane, from anterior to posterior.2. Fi (published by Finlayson): US probe in the transverse plane to visualize a cervical articular pillar and its lamina, needle approach in the plane, from posterior to anterior.3. FiM (Modified Finlayson approach): Needles are placed as in Fi, but then adjusted with a coronal view of the cervical articular pillars.Fluoroscopy images were taken and later evaluated, for "crude", "high precision" and "dangerous" placement. RESULTS: One hundred and fifty-five needle placements were assessed (10 were excluded, as no anterior-posterior fluoroscopy images were saved). Interobserver agreement on position of needle placement between the 5 observers was very high; the Fleiss' Kappa was 0.921. For crude placement, no significant differences were identified between various approaches; (77.6%, 79.5%, and 75.6% for the ES, Fi, and FiM respectively). However, for placement in predefined high-precision zones, ES resulted in significantly more success (ES: 42.9%, Fi: 22.7%, and FiM: 24.4%, P = 0.032). Fi and FiM resulted in no dangerous placements, while ES led to the potential compromise of the exiting nerve root and vertebral artery on three occasions. In 10% of the placements, the levels were identified wrongly, with no difference between the various approaches. LIMITATIONS: Feedback from a live patient, may prevent some existing nerve root injections, unlike in a cadaver. Though a higher number of needles were placed in this study than in most available publications, the number is still low at each individual medial branch level. CONCLUSION: Fi proved safer than ES. Fi was equally successful in targeting the articular pillar, however, ES proved the most successful in placing the needle in the center of the articular pillar. Adding another, (coronal) US view to check needle position in FiM did not improve safety or precision. Identifying CMB levels with the US is challenging with all approaches, therefore we still recommend using fluoroscopy for level identification. While there were pros and cons with either procedure, the efficacy findings of previous papers were not replicated on elderly cadavers with arthritic necks.

Percutaneous Radiofrequency Ablation for Trigeminal Neuralgia Management: A Randomized, Double-Blinded, Sham-Controlled Clinical Trial.

Trigeminal neuralgia, considered by many the worst pain that humankind can experience, has been called "the suicide disease." Neuroablative procedures are good options when conservative treatment fails to promote pain relief or in those whose side effects are unbearable. The objective was to compare the effectiveness and safety of trigeminal percutaneous radiofrequency ablation in classical refractory trigeminal neuralgia in a prospective, randomized, double-blind, sham-controlled clinical trial. We included 30 consecutive patients with classical trigeminal neuralgia who had failed to respond to drug treatment. The patients were randomly assigned into two groups: a thermal radiofrequency and a sham group. The thermal radiofrequency group were submitted to a 75°C lesion for 60 seconds after proper sensory and motor stimulation. All steps were carried out in the sham group except the thermal lesion. Patients were evaluated using the Numerical Rating Scale (NRS), the 36-Item Short-Form Health Survey questionnaire, and anticonvulsant dose. After 1 month, the mean NRS score decreased from 9.2 to 0.7 in the radiofrequency group and from 8.9 to 5.8 in the sham group. This significant reduction was measurable starting at day one after the procedure and remained significant throughout the first month. Changing groups was allowed after one month, after which the pain reduction was similar between the two groups. Percutaneous trigeminal radiofrequency ablation results in statistically and clinically significant greater pain relief than the sham procedure after 1 month of follow-up. These results support using radiofrequency nerve ablation as a treatment for refractory trigeminal neuralgia.

An alternative approach for blocking the superior trunk of the brachial plexus evaluated by a single arm clinical trial

Abstract Background Interscalene brachial plexus block is associated with phrenic nerve paralysis. The objective of this study was to evaluate an alternative approach to interscalene brachial plexus blocks in terms of efficacy, grade of motor and sensory blockade, and phrenic nerve blockade. Methods The study was prospective and interventional. The ten living patients studied were 18 to 65 years old, ASA physical status I or II, and submitted to correction of rotator cuff injury. A superior trunk blockade was performed at the superior trunk below the omohyoid muscle, without blocking the phrenic nerve. The needle was advanced below the prevertebral layer until contacting the superior trunk. In order to guarantee the correct positioning of the needle tip, an intracluster pattern of the spread was visualized. The block was performed with 5 mL of 0.5% bupivacaine in ten patients. In the six cadavers, 5 mL of methylene blue was injected. Diaphragmatic excursion was assessed by ultrasonography of the ipsilateral hemidiaphragm. In three patients, pulmonary ventilation was evaluated with impedance tomography. Pain scores and analgesic consumption were assessed in the recovery room for 6 hours after the blockade. Results In the six cadavers, methylene blue didn't reach the phrenic nerve. Ten patients underwent arthroscopic surgery, and no clinically phrenic nerve paralysis was observed. No patient reported pain during the first 6 hours. Conclusions This study suggests that this new superior trunk approach to block the superior trunk may be an alternative technique to promote analgesia for shoulder surgery in patients with impaired respiratory function.

An alternative approach for blocking the superior trunk of the brachial plexus evaluated by a single arm clinical trial.

BACKGROUND: Interscalene brachial plexus block is associated with phrenic nerve paralysis. The objective of this study was to evaluate an alternative approach to interscalene brachial plexus blocks in terms of efficacy, grade of motor and sensory blockade, and phrenic nerve blockade. METHODS: The study was prospective and interventional. The ten living patients studied were 18 to 65 years old, ASA physical status I or II, and submitted to correction of rotator cuff injury. A superior trunk blockade was performed at the superior trunk below the omohyoid muscle, without blocking the phrenic nerve. The needle was advanced below the prevertebral layer until contacting the superior trunk. In order to guarantee the correct positioning of the needle tip, an intracluster pattern of the spread was visualized. The block was performed with 5.ßmL of 0.5% bupivacaine in ten patients. In the six cadavers, 5.ßmL of methylene blue was injected. Diaphragmatic excursion was assessed by ultrasonography of the ipsilateral hemidiaphragm. In three patients, pulmonary ventilation was evaluated with impedance tomography. Pain scores and analgesic consumption were assessed in the recovery room for 6.ßhours after the blockade. RESULTS: In the six cadavers, methylene blue didn...t reach the phrenic nerve. Ten patients underwent arthroscopic surgery, and no clinically phrenic nerve paralysis was observed. No patient reported pain during the first 6.ßhours. CONCLUSIONS: This study suggests that this new superior trunk approach to block the superior trunk may be an alternative technique to promote analgesia for shoulder surgery in patients with impaired respiratory function.

Peripheral Nerve Stimulation of the Brachial Plexus for Chronic Refractory CRPS Pain of the Upper Limb: Description of a New Technique and Case Series.

OBJECTIVE: Upper limb complex regional pain syndrome is an important cause of chronic pain, and its treatment is challenging. In this pilot case series, we preliminarily evaluated the feasibility, effectiveness, and safety of a new technique for brachial plexus neuromodulation in the treatment of this disease in patients refractory to conservative treatment. METHODS: Between 2017 and 2018, 14 patients considered to be refractory to optimized conservative treatment were recruited to this study. In the first stage, patients were trialed for seven days with a new technique of implant of the brachial plexus. Patients with ≥50% pain relief in visual analog scale (VAS) score received a definitive implantation in the second stage. Follow-ups were conducted at pre-implant and 12 months using the Neuropathic Pain Scale, SF-32, and the visual analogic scale for pain. RESULTS: After the initial trial, 10 patients had a pain reduction of ≥50% and received a permanent implant. At 12-month follow-up, VAS, Neuropathic Pain Scale, SF-12 physical and mental scores improved by 57.4% +/- 10% (P = 0.005), 60.2% +/- 12.9% (P = 0.006), and 21.9% +/- 5.9% (P = 0.015), respectively. CONCLUSIONS: Our data suggest that this new technique of brachial plexus stimulation may have long-term utility in the treatment of painful upper limb complex regional pain syndrome. New more detailed comprehensive studies should be carried out to confirm our findings in a larger population and to further refine the clinical implementation of this technique.

Caudal epidural anesthesia: an anesthetic technique exclusive for pediatric use? Is it possible to use it in adults? What is the role of the ultrasound in this context?

BACKGROUND AND OBJECTIVES: Caudal epidural anesthesia is the most popular regional anesthesia technique used in children. With advanced age, only the relative difficulty in localizing the sacral hiatus limits its use. However, in adults this technique has been widely used to control chronic pain by adjuvant use of fluoroscopy. Thus, the ability to locate the hiatus and define anatomical variations is the main determinant of the success and safety of caudal epidural anesthesia. In this context, the use of the ultrasound in caudal epidural anesthesia has been increasing. The objective of this review was to determine the role of the ultrasound in caudal epidural anesthesia and to demonstrate that this technique, widely used in children, is also useful and can be used in adults. CONTENT: A review of the literature on sacral anatomy and the anesthetic technique necessary to perform caudal epidural anesthesia was undertaken. Recent studies in ultrasound-guided caudal epidural anesthesia both in children and adults were also included. CONCLUSIONS: Despite its limitations, the ultrasound can be a useful tool to position the needle in the caudal space. It allows prompt identification of the sacral anatomy and real-time visualization of the injection. Considering it is portable, non-invasive, and free of radiation exposure, it is an attractive technique in the operating room especially in difficult cases. However, since its use in neuroaxis anesthesia is very primitive, more studies are necessary to make it a routine technique in anesthetic practice.

Bloqueio peridural caudal: técnica anestésica de uso exclusivo em crianças? É possível sua realização em adultos? Qual o papel do ultrassom nesse contexto? / Caudal epidural anesthesia: an anesthetic technique exclusive for pediatric use? Is it possible to use it in adults? What is the role of the ultrasound in this context? / Bloqueo epidural caudal: ¿técnica anestésica de uso exclusivo en niños? ¿Se puede realizar en adultos? ¿Cuál es el rol del ultrasonido en ese contexto?

JUSTIFICATIVA E OBJETIVOS: O bloqueio peridural caudal é a mais popular entre todas as técnicas de anestesia regional em crianças. Com o avanço da idade, apenas a relativa dificuldade em localizar o hiato sacral limita seu uso. Entretanto, em adultos a técnica vem sendo largamente utilizada para controle de dor crônica com o auxílio da fluoroscopia. Assim, a habilidade em localizar o hiato e definir as variações anatômicas é o principal fator determinante do sucesso e segurança na execução do bloqueio peridural pela via caudal. Nesse contexto, o ultrassom vem ganhando espaço como guia para a realização do bloqueio caudal. O objetivo desta revisão foi elucidar o papel do ultrassom na anestesia caudal, além de demonstrar que o bloqueio caudal, muito utilizado em crianças, também é útil e pode ser usado em adultos. CONTEÚDO: Uma revisão literária sobre a anatomia da região sacral e da técnica anestésica necessária para a realização adequada do bloqueio caudal foi promovida. Além disso, artigos recentes sobre estudos realizados com bloqueios peridurais caudais guiados por ultrassom tanto em crianças quanto em adultos também foram incluídos. CONCLUSÕES: O ultrassom, apesar de suas limitações, pode ser útil como ferramenta adjuvante no posicionamento da agulha no espaço caudal. Permite a fácil identificação da anatomia sacral, além de visualização da injeção, em tempo real. Sua natureza portátil, não invasiva e livre de exposição à radiação faz dele uma tecnologia atrativa na sala operatória, principalmente na emergência de casos difíceis. Entretanto, como seu uso em bloqueios centrais do neuroeixo ainda é muito primitivo, é necessário que mais pesquisas sejam feitas para se consagre como técnica de rotina na prática anestésica.

BACKGROUND AND OBJECTIVES: Caudal epidural anesthesia is the most popular regional anesthesia technique used in children. With advanced age, only the relative difficulty in localizing the sacral hiatus limits its use. However, in adults this technique has been widely used to control chronic pain by adjuvant use of fluoroscopy. Thus, the ability to locate the hiatus and define anatomical variations is the main determinant of the success and safety of caudal epidural anesthesia. In this context, the use of the ultrasound in caudal epidural anesthesia has been increasing. The objective of this review was to determine the role of the ultrasound in caudal epidural anesthesia and to demonstrate that this technique, widely used in children, is also useful and can be used in adults. CONTENT: A review of the literature on sacral anatomy and the anesthetic technique necessary to perform caudal epidural anesthesia was undertaken. Recent studies in ultrasound-guided caudal epidural anesthesia both in children and adults were also included. CONCLUSIONS: Despite its limitations, the ultrasound can be a useful tool to position the needle in the caudal space. It allows prompt identification of the sacral anatomy and real-time visualization of the injection. Considering it is portable, non-invasive, and free of radiation exposure, it is an attractive technique in the operating room especially in difficult cases. However, since its use in neuroaxis anesthesia is very primitive, more studies are necessary to make it a routine technique in anesthetic practice.

JUSTIFICATIVA Y OBJETIVOS: El bloqueo epidural caudal es la más popular entre todas las técnicas de anestesia regional en niños. Cuando la edad avanza, apenas la relativa dificultad en localizar el hiato sacral limita su uso. Sin embargo, en los adultos, la técnica ha venido siendo ampliamente utilizada para el control del dolor crónico, con la ayuda de la fluoroscopía. Por lo tanto, la habilidad en poder ubicar el hiato y definir las variaciones anatómicas es el principal factor determinante del éxito y de la seguridad en la ejecución del bloqueo epidural por la vía caudal. En ese contexto, el ultrasonido ha venido ganando espacio como guía para la realización del bloqueo caudal. El objetivo de esta revisión fue elucidar el papel del ultrasonido en la anestesia caudal, además de demostrar que el bloqueo caudal, muy utilizado en niños, también es útil y puede ser usado en adultos. CONTENIDO: Se hizo una revisión literaria sobre la anatomía de la región sacral y de la técnica anestésica necesaria para la adecuada realización del bloqueo caudal. Además, también se incluyeron artículos recientes sobre estudios realizados con bloqueos epidurales caudales guiados por ultrasonido tanto en niños como en adultos. CONCLUSIONES: El ultrasonido, a pesar de sus limitaciones, puede ser útil como una herramienta coadyuvante en el posicionamiento de la aguja en el espacio caudal. Permite la fácil identificación de la anatomía sacral, además de la visualización de la inyección en tiempo real. Su naturaleza portátil, no invasiva y libre de exposición a la radiación, lo convierte en una tecnología atractiva en quirófano, principalmente en las situaciones de emergencia de casos complicados. Sin embargo, como su uso en bloqueos centrales del neuro eje todavía es muy primitivo, se hacen necesarias más investigaciones para que se consagre como una técnica de rutina en la práctica anestésica.