Ultrasound-guided anterior approach to the axillary and intercostobrachial nerves in the axillary fossa: an anatomical investigation

Axillary nerve: what anesthesiologists and pain physicians should know

Innervation of the shoulder joint is complex and remains poorly understood among regional anesthesiologists and chronic pain specialists. Current literature supports the important contribution of the axillary nerve to the total innervation of the shoulder, as well as its blockade for perioperative pain and denervation for chronic shoulder pain. However, a description of the entire course of the axillary nerve, the corresponding optimal targets, and the sonoanatomy pertinent to pain intervention is lacking. This educational article discusses in detail the functional anatomy and sonographic identification of possible windows for axillary nerve intervention. We discuss the contribution, extent, and type of innervation the axillary nerve provides to the shoulder joint, which is often misunderstood. Ultimately, this article serves to stimulate thoughts and ideas for future research in an area where literature is scarce.

Randomized comparison between ultrasound-guided proximal and distal approaches of intercostobrachial nerve block as an adjunct to supraclavicular brachial plexus block for upper arm arteriovenous access procedures

BACKGROUNDS

Ultrasound-guided proximal and distal approaches of the intercostobrachial nerve (ICBN) blocks facilitate analgesia for upper arm and axillary surgery, though success rates vary and lack clinical comparison. This study compared their anesthetic and analgesic efficacy as an adjunct to the supraclavicular brachial plexus block for upper arm arteriovenous access surgery.

METHODS

60 end-stage renal disease patients undergoing upper arm arteriovenous access were randomly assigned to receive either proximal or distal ICBN block using 10 mL of a mixture of levobupivacaine and lidocaine with epinephrine. The primary outcome was a successful ICBN block, defined as a cutaneous sensory blockade at both the medial upper arm and axilla 30 min after the block. Secondary outcomes included block performance, block-related complications, rate of surgical anesthesia, and postoperative analgesia.

RESULTS

The proximal approach had a higher percentage of sensory blockade at the axilla (96.7% vs 73.3%, p=0.03), but comparable rates at the medial upper arm (96.7% vs 96.7%, p=1.00). Consequently, the proximal approach had a higher overall success rate (96.7% vs 73.3%, difference: 23.3%; 95% CI: 6.3%, 40.4%; p=0.03). Both groups had similar surgical anesthesia rates of 93.3%. No significant differences were found in performance time, procedural pain, or postoperative pain intensity.

CONCLUSIONS

Proximal ICBN block consistently reduced sensation in the medial upper arm and axilla, while one-quarter of distal blocks spared the axilla. Both approaches, in combination with a supraclavicular brachial plexus block, were effective for upper arm arteriovenous access procedures. However, the proximal approach may be preferable for axillary surgery.

TRIAL REGISTRATION NUMBER

TCTR20200730006.

Dissimilar Planes and Approaches with Common Neural Targets - A Cadaveric Evaluation of Three Different Ultrasound-guided Fascial Plane Blocks for Lumbar Plexus Nerves

Background

The lumbar plexus (LP) is a group of nerves located at the fourth lumbar vertebra level, between the anterior two-thirds and posterior one-thirds of the psoas muscle. In this study, the researchers aimed to investigate the spread of latex in injections of LP, suprainguinal fascia iliaca, and circum-psoas planes to assess the different regional techniques for blocking LP nerves (LPNs).

Methods

The study involved performing ultrasound-guided injections of three different colored latexes in six cadavers. The researchers observed and compared the spread of latex in each plane by taking cross sections at the levels of L4, anterior superior iliac spine (ASIS), and sacral foramina (SF). The spread of latex and LPN staining was documented and analyzed through photography.

Results

The results showed that the latex spread within the psoas muscle and fascia iliaca plane (FIP) during LP injections, whereas suprainguinal fascia iliaca injections showed latex dissemination in the FIP at both ASIS and SF levels. On the other hand, circum-psoas injections spread beneath the iliopsoas fascia at both levels and medially toward the external iliac vessels. Despite this spread, there was no communication between the three planes, and there was no mixing of latex from the different injections at any level.

Conclusion

There are distinct fascial planes, for the three approaches, with no communication between them. While latex diffused from LP plane to FIP, no mixing of dye was observed and also the reverse could not be achieved. These findings suggest that different regional techniques for blocking LPNs have their unique planes of action.

Regional Anesthesia Techniques for Shoulder Surgery in High-Risk Pulmonary Patients

Patients with pre-existing pulmonary conditions are at risk for experiencing perioperative complications and increased morbidity. General anesthesia has historically been used for shoulder surgery, though regional anesthesia techniques are increasingly used to provide anesthesia and improved pain control after surgery. Relative to regional anesthesia, patients who undergo general anesthesia may be more prone to risks of barotrauma, postoperative hypoxemia, and pneumonia. High-risk pulmonary patients, in particular, may be exposed to these risks of general anesthesia. Traditional regional anesthesia techniques for shoulder surgery are associated with high rates of phrenic nerve paralysis which significantly impairs pulmonary function. Newer regional anesthesia techniques have been developed, however, that provide effective analgesia and surgical anesthesia while having much lower rates of phrenic nerve paralysis, thereby preserving pulmonary function.

Quadrangular Space Syndrome: a systematic review of surgical and medical therapeutic advances

Background

The axillary nerve and posterior circumflex humeral artery are compressed in Quadrangular Space Syndrome (QSS), which can be treated with conservative approaches or surgical decompression in recalcitrant instances. There are no clear guidelines for determining which surgical method is optimal for treating QSS and other disorders that mirror QSS.

Objective

The goal of this study is to grade and review past, current, and planned medicinal and surgical care modalities for QSS.

Materials and Methods

The review protocol is registered with PROSPERO (ID: CRD42022332766). To identify recent advances in the methods/techniques of medical and surgical management of QSS, PubMed and Medline databases were searched until March 2022 for publications, including case studies, case reports, and review articles, using medical subject headings terms like quadrilateral space syndrome, surgical management, and medical management. Throughout the study, all the authors scrupulously followed a well-developed registered review process and the risk of bias in systematic reviews guidance tool. Data on proposed medical and surgical management methods/techniques were compiled, and each was analyzed based on the underlying neuro-vascular systems.

Results

There were 88 items found in the first search. Following applying the inclusion and exclusion criteria, 16 papers were chosen for synthesis in the review study after a thorough assessment. Three studies (conservative and advanced) focused on medical care of QSS, while 12 articles (prior, current, and newer) focused on surgical management of QSS. Only four of the 15 studies reviewed proposed different surgical approaches/techniques for surgical decompression in QSS.

Conclusions

There were two regularly used surgical procedures discovered, one anterior/delto-pectoral and the other posterior/ scapular. The anterior route is more technically straightforward and can be employed for surgical QSS decompression.

Revisiting the Surgical Approaches to Decompression in Quadrilateral Space Syndrome: A Cadaveric Study

Background

Quadrangular space syndrome involves compression of the axillary nerve and posterior circumflex humeral artery. In a few cases, its management requires surgical decompression. The current study reviews the surgical approaches used in the decompression of neurovascular structures and presents our reflections and recommendations.

Methodology

In this study, four human cadavers were used for dissection of the axillae and the scapular region by the senior residents of the Department of Anatomy and Department of Orthopedics. The residents dissected the quadrangular space in the eight upper limbs using anterior and posterior surgical approaches.

Results

To identify the quadrangular space and secure its contents, the posterior approach was recognized as the easier and quicker method by both Anatomy and Orthopedic residents; however, it may result in increased postoperative morbidity. Although the anterior (deltopectoral) approach involves more skill, it reduces postoperative morbidity.

Conclusions

The anterior (deltopectoral) approach with suggested modifications can be an effective method in the surgical decompression of quadrangular space syndrome. The authors suggest more cadaveric studies to provide anatomists and surgeons with the opportunity to practice and evaluate older and newer surgical approaches.

Evaluation of Interfascial Plane and Pericapsular Nerve Blocks to the Shoulder Joint: A Preliminary Analysis of Shoulder Anterior Capsular Block

INTRODUCTION

The aim of this study is to verify if the shoulder anterior capsular block (SHAC), combined with other nerve blocks, is effective in relieving shoulder pain, avoiding motor block and allowing an early rehabilitation program.

METHODS

Seventy-five consecutive patients with painful shoulder were treated with the SHAC, alone (30 patients) or in combination with a suprascapular nerve block (SSnb: 25 patients) or with pectoralis and serratus plane block (PECS-2: 20 patients). All blocks were performed with 0.2% ropivacaine plus 8 mg dexamethasone. All patients were treated with three-weekly physiotherapy sessions for the following 2 weeks and then with home exercises.

RESULTS

The post-procedural analgesic effect was strong in all groups, with a mean change in numeric rating scale (NRS) values of -6.05 in group 1, -6.25 in group 2, and -6.19 in group 3 (p < .0001), allowing all patients to complete an immediate physiotherapy session. Only a few patients needed to repeat the procedure 1 week after the first treatment for the recurrence of pain. From the treatment to the end of the follow-up, we noted a further drop in mean pain NRS values of 1.90 in group 1 and 1.80 in groups 2 and 3. No difference in effect over time was observed among the different groups. No adverse event or motor block was recorded.

CONCLUSION

This study demonstrates that the SHAC, alone or in combination with other peripheral nerve blocks, is an attractive alternative for shoulder pain management, especially when physiotherapy is required to recover shoulder function.

Permeable spaces between glenohumeral ligaments as potential gateways for rapid regional anesthesia of the shoulder

Shoulder pain is a highly prevalent condition, often resulting in major life limitations, and requiring effective treatments. In this work, we explore the anatomical basis of a proposed approach to the regional anesthesia of the shoulder through a single injection under the subscapularis muscle. Bilateral experimental injections in shoulders from body donors (Radiolar ® and Methylene-Blue) under the subscapular muscle (n = 11) and cadaveric systematic dissections of other 35 shoulders from body donors were performed. Injectate spread was then qualitatively assessed. Long axis of permeable foramina in the anterior aspect of the shoulder joint capsule was measured in centimeters using a digital caliper. More than 40% of specimens had at least one permeable space (Weitbrech and/or Rouvière foramina) communicating the subscapular bursa and the articular space. We further demonstrate that an ultrasonography-guided injection under the subscapularis muscle allows the spread of the injectate through the anterior, inferior and posterodorsal walls of the articular capsule, the subacromial bursa, and the bicipital groove, as well as into the articular space for some injections. The odds of accidental intraarticular injection decrease when injecting with low volumes. This anatomical study provides a detailed description of foramina between glenohumeral ligaments. Furthermore, the data shown in this work supports, as a proof of concept, a safe alternative for rapid and specific blockade of terminal sensory branches innervating the shoulder joint capsule.

Cadaveric study identifying clinical sonoanatomy for proximal and distal approaches of ultrasound-guided intercostobrachial nerve block

Background and objectives

The intercostobrachial nerve (ICBN) has significant anatomical variation. Localization of the ICBN requires an operator’s skill. This cadaveric study aims to describe two simple ultrasound-guided plane blocks of the ICBN when it emerges at the chest wall (proximal approach) and passes through the axillary fossa (distal approach).

Methods

The anatomical relation of the ICBN and adjacent structures was investigated in six fresh cadavers. Thereafter, we described two potential techniques of the ICBN block. The proximal approach was an injection medial to the medial border of the serratus anterior muscle at the inferior border of the second rib. The distal approach was an injection on the surface of the latissimus dorsi muscle at 3–4 cm caudal to the axillary artery. The ultrasound-guided proximal and distal ICBN blocks were performed in seven hemithoraxes and axillary fossae. We recorded dye staining on the ICBN, its branches and clinically correlated structures.

Results

All ICBNs originated from the second intercostal nerve and 34.6% received a contribution from the first or third intercostal nerve. All ICBNs gave off axillary branches in the axillary fossa and ran towards the posteromedial aspect of the arm. Following the proximal ICBN block, dye stained on 90% of all ICBN’s origins. After the distal ICBN block, all terminal branches and 43% of the axillary branches of the ICBN were stained.

Conclusions

The proximal and distal ICBN blocks, using easily recognized sonoanatomical landmarks, provided consistent dye spread to the ICBN. We encourage further validation of these two techniques in clinical studies.

Anatomy of the brachial plexus and its implications for daily clinical practice: regional anesthesia is applied anatomy

Safety and effectiveness are mandatory requirements for any technique of regional anesthesia and can only be met by clinicians who appropriately understand all relevant anatomical details. Anatomical texts written for anesthetists may oversimplify the facts, presumably in an effort to reconcile extreme complexity with a need to educate as many users as possible. When it comes to techniques as common as upper-extremity blocks, the need for customized anatomical literature is even greater, particularly because the complex anatomy of the brachial plexus has never been described for anesthetists with a focus placed on regional anesthesia. The authors have undertaken to close this gap by compiling a structured overview that is clinically oriented and tailored to the needs of regional anesthesia. They describe the anatomy of the brachial plexus (ventral rami, trunks, divisions, cords, and nerves) in relation to the topographical regions used for access (interscalene gap, posterior triangle of the neck, infraclavicular fossa, and axillary fossa) and discuss the (interscalene, supraclavicular, infraclavicular, and axillary) block procedures associated with these access regions. They indicate allowances to be made for anatomical variations and the topography of fascial anatomy, give recommendations for ultrasound imaging and needle guidance, and explain the risks of excessive volumes and misdirected spreading of local anesthetics in various anatomical contexts. It is hoped that clinicians will find this article to be a useful reference for decision-making, enabling them to select the most appropriate regional anesthetic technique in any given situation, and to correctly judge the risks involved, whenever they prepare patients for a specific upper-limb surgical procedure.

[Outpatient treatment of acute injuries of upper extremities with axillary plexus anesthesia in the emergency department-Is that possible without continuous anesthesia attendance?]

BACKGROUND

The incorporation into the routine operating procedure of patients with small but acute hand and forearm injuries requiring surgery who present in the emergency admission department, represents a challenge due to limited resources. The prompt treatment in the emergency admission department represents an alternative. This article retrospectively reports the authors' experiences with a treatment algorithm in which emergency patients were treated by ultrasound-guided axillary brachial plexus blocks (ABPB) and surgery carried out in the emergency department without further anesthesia attendance.

METHODS

Patients were preselected by the surgeon if they were suitable for a standardized treatment without anesthesia attendance during surgery. If there were no anesthesiological or surgical contraindications patients received an ABPB in the holding area of the operating room (OR) under standard monitoring. Blocks were performed as a multi-injection, ultrasound-guided technique which is anatomically described in detail. Patients >60 kg received a total volume of 30 ml of a mixture of 10 ml 1% ropivacaine (100 mg) and 20 ml 2% prilocaine (400 mg). Patients <60 kg received the same mixture with a reduced volume of 25 ml corresponding to 82.5 mg ropivacaine and 332.5 mg prilocaine. After controlling for block success patients were admitted to the emergency department and the surgical procedure was carried out under supervision by the surgeon without further anesthesia attendance. At discharge patients were explicitly instructed that in the case of any complications or a continuation of the block for more than 24 h they should contact the emergency department.

RESULTS

Between January 2013 and November 2017 a total of 566 patients (46.4 years, range 11-88 years, 174.9 cm, range 140-211cm, 80.8 kg, range 42-178kg, ASA 1/2/3, 190/338/38, respectively) were treated according to a standardized protocol. The ABPBs were performed by 74 anesthetists. In 5% of the patients the initial block was incomplete and rescue blocks were performed with a maximum of 2‑3ml 1% prilocaine per corresponding nerve. After completion the block was ensured and all patients underwent surgery without further analgesics or local anesthetic infiltration by the surgeon. Complications related to the ABPB and readmissions were not observed.

CONCLUSION

It could be demonstrated that minor surgery could be carried out safely and effectively with a defined algorithm using ABPB in selected patients outside the OR without permanent anesthesia attendance: however, indispensable prerequisites for such procedures are careful patient selection, patient compliance, the safe and effective performance of the ABPB and reliable agreement with the surgeon.

Upper extremity regional anesthesia techniques: A comprehensive review for clinical anesthesiologists

Surgeries and chronic pain states of the upper extremity are quite common and pose unique challenges for the clinical anesthesiology and pain specialists. Most innervation of the upper extremity involves the brachial plexus. The four most common brachial plexus blocks performed in clinical setting include the interscalene, supraclavicular, infraclavicular, and axillary brachial plexus blocks. These blocks are most commonly performed with the use of ultrasound-guided techniques, whereby analgesia is achieved by anesthetizing the brachial plexus at different levels such as the roots, divisions, cords, and branches. Additional regional anesthetic techniques for upper extremity surgery include wrist, intercostobrachial, and digital nerve blocks, which are most frequently performed using landmark anatomical techniques. This review provides a comprehensive summary of each of these blocks including anatomy, best practice techniques, and potential complications.

Regional anesthesia for vascular surgery: does the anesthetic choice influence outcome?

PURPOSE OF REVIEW

Outcomes following surgery are of major importance to clinicians, institutions and most importantly patients. This review examines whether regional anesthesia and analgesia influence outcome after vascular surgery.

RECENT FINDINGS

Large database analyses of contemporary practice suggest that utilizing regional anesthesia for both open and endovascular aortic aneurysm repair, lower limb revascularization and carotid endarterectomy reduces morbidity, length of stay and possibly even mortality. Results from such analyses are limited by an inherent risk of bias but are nevertheless important given the number of patients required in randomized trials to detect differences in rare outcomes. There is minimal evidence that regional anesthesia influences longer term outcomes except for arteriovenous fistula surgery where brachial plexus blocks appear to improve 3-month fistula patency.

SUMMARY

Patients undergoing vascular surgery often have multiple comorbidities and it is important to be able to outline both benefits and risks of regional anesthesia techniques. Regional anesthesia in vascular surgery allows avoidance of general anesthesia and does provide short-term benefits beyond superior analgesia. Evidence of long-term benefits is lacking in most procedures. Further work is required on newer patient centered outcomes.

Usefulness of high-resolution ultrasound for small nerve blocks: visualization of intercostobrachial and medial brachial cutaneous nerves in the axillary area

INTRODUCTION

High-resolution ultrasound (HRU) allows one to identify small nerves, but in the clinical setting, intercostobrachial nerve (ICBN) and medial brachial cutaneous nerve (MBCN) are not identified with conventional portable ultrasound (CPU) devices. The aim of this study is to identify both nerves and describe their relation with specific anatomical structures which could be easily identified with the ultrasound devices available in the clinical setting.

METHODS

21 healthy patients were scanned using HRU bilaterally in the axillary area located over the conjoint tendon to find the ICBN and MBCN and describe their anatomic relations. 5 fresh cadavers were used to validate the previous anatomical findings. ICBN and MBCN ultrasound-guided block was performed with 5 mL of methylene blue and iodine contrast, and the distribution was assessed by both CT scan and dissection.

RESULTS

ICBN and MBCN were identified in all cases. The average distance of the ICBN branches to the artery was 35±6 mm in men and 27±5 mm in women. Constant identification of the muscle-tendon junction of the latissimus dorsi muscle with respect to the location of the branches of the ICBN nerve was observed. Dissection and CT scan confirmed these findings.

CONCLUSION

HRU is a useful tool to identify ICBN and MBCN nerves, and to describe structures which can be easily identified with CPU use in the clinical setting.

Ultrasonography-guided anterior approach for axillary nerve blockade: An anatomical study

Combined ultrasound (US)-guided blockade of the suprascapular and axillary nerves (ANs) has been proposed as an alternative to interscalene blockade for pain control in shoulder joint pathology or postsurgical care. This technique could help avoid respiratory complications and/or almost total upper limb palsy. Nowadays, the AN blockade is mostly performed using an in-plane caudal-to-cephalic approach from the posterior surface of the shoulder, reaching the nerve immediately after it exits the neurovascular quadrangular space (part of the spatium axillare). Despite precluding most respiratory complications, this approach has not made postsurgical pain relief any better than an interscalene blockade, probably because articular branches of the AN are not blocked.Cephalic-to-caudal methylene blue injections were placed in the first segment of the AN of six Thiel-embalmed cadavers using an US-guided anterior approach in order to compare the distribution with that produced by a posterior approach to the contralateral AN in the same cadaver. Another 21 formalin-fixed cadavers were bilaterally dissected to identify the articular branches of the AN.We found a good spread of the dye on the AN and a constant relationship of this nerve with the subscapularis muscle. The dye reached the musculocutaneous nerve, which also contributes to shoulder joint innervation. We describe the anatomical landmarks for an ultrasonography-guided anterior AN blockade and hypothesize that this anterior approach will provide better pain control than the posterior approach owing to complete blocking of the joint nerve. Clin. Anat. 33:488-499, 2020. © 2019 Wiley Periodicals, Inc.