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Regional Anesthesia For the Elbow, Forearm, & Wrist

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Authors

Landon Mueller, MD

Summary & Introduction

  • Injuries to the elbow most commonly happen from a fall on outstretched hand (FOOSH) or a direct blow to the elbow.[1]Goldflam K. Evaluation and treatment of the elbow and forearm injuries in the emergency department. Emerg Med Clin North Am. 2015;33(2):409-421. doi:10.1016/j.emc.2014.12.010Injuries to the elbow account for approximately 5-10% of all fractures.[2]Hanlon DP, Mavrophilipos V. The Emergent Evaluation and Treatment of Elbow and Forearm Injuries. Emerg Med Clin North Am. 2020;38(1):81-102. doi:10.1016/j.emc.2019.09.005
  • Elbow and humeral trauma have a high potential for complications and disability, requiring quick treatment for neurovascular and soft-tissue compromise.[3]Bookman K. Humerus and Elbow. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen’s Emergency Medicine: Concepts and Clinical Practice. Ninth edition. Elsevier; 2018:530-548
  • Therefore, the primary goal of all elbow and distal humerus injuries is to achieve anatomic reduction of dislocations and fractures.[4]Goldflam K. Evaluation and treatment of the elbow and forearm injuries in the emergency department. Emerg Med Clin North Am. 2015;33(2):409-421. doi:10.1016/j.emc.2014.12.010
  • The most common elbow and distal humerus injuries seen in the emergency department include elbow dislocations, radial head fractures, and distal humerus fractures. Less commonly are coronoid process, olecranon and radial neck fractures.[5]Goldflam K. Evaluation and treatment of the elbow and forearm injuries in the emergency department. Emerg Med Clin North Am. 2015;33(2):409-421. doi:10.1016/j.emc.2014.12.010[6]Karl JW, Olson PR, Rosenwasser MP. The Epidemiology of Upper Extremity Fractures in the United States, 2009. J Orthop Trauma. 2015;29(8):e242-244. doi:10.1097/BOT.0000000000000312
    • Acute elbow dislocations
      • The second most common large joint dislocation (after shoulder).[7]Layson J, Best BJ. Elbow Dislocation. In: StatPearls. StatPearls Publishing; 2020. Accessed February 7, 2021. http://www.ncbi.nlm.nih.gov/books/NBK549817/Estimated incidence is 5.21 dislocations per 100,000 person-years, adolescent males are at highest risk.[8]Stoneback JW, Owens BD, Sykes J, Athwal GS, Pointer L, Wolf JM. Incidence of elbow dislocations in the United States population. J Bone Joint Surg Am. 2012;94(3):240-245. doi:10.2106/JBJS.J.01663
      • Most common mechanisms are a fall on to an outstretched arm (42-56%), high-energy trauma (bicycle accident, motor vehicle accident, snow sports accident), or a fall from great height.[9]Stoneback JW, Owens BD, Sykes J, Athwal GS, Pointer L, Wolf JM. Incidence of elbow dislocations in the United States population. J Bone Joint Surg Am. 2012;94(3):240-245. doi:10.2106/JBJS.J.01663[10]Mühlenfeld N, Frank J, Lustenberger T, Marzi I, Sander AL. Epidemiology and treatment of acute elbow dislocations: current concept based on primary surgical ligament repair of unstable simple elbow … Continue reading
      • The vast majority are posterior dislocations (79%)[11]Mühlenfeld N, Frank J, Lustenberger T, Marzi I, Sander AL. Epidemiology and treatment of acute elbow dislocations: current concept based on primary surgical ligament repair of unstable simple elbow … Continue reading
      • A simple dislocation does not have any associated fractures, and account for 42% of dislocations. Complex dislocations occur with periarticular fractures, most commonly radial head + ulnar coronoid process.[12]Layson J, Best BJ. Elbow Dislocation. In: StatPearls. StatPearls Publishing; 2020. Accessed February 7, 2021. http://www.ncbi.nlm.nih.gov/books/NBK549817/[13]Mühlenfeld N, Frank J, Lustenberger T, Marzi I, Sander AL. Epidemiology and treatment of acute elbow dislocations: current concept based on primary surgical ligament repair of unstable simple elbow … Continue reading
      • Classically require procedural sedation for reduction.[14]Goldflam K. Evaluation and treatment of the elbow and forearm injuries in the emergency department. Emerg Med Clin North Am. 2015;33(2):409-421. doi:10.1016/j.emc.2014.12.010[15]Hanlon DP, Mavrophilipos V. The Emergent Evaluation and Treatment of Elbow and Forearm Injuries. Emerg Med Clin North Am. 2020;38(1):81-102. doi:10.1016/j.emc.2019.09.005
    • Radial head fractures[16]Hanlon DP, Mavrophilipos V. The Emergent Evaluation and Treatment of Elbow and Forearm Injuries. Emerg Med Clin North Am. 2020;38(1):81-102. doi:10.1016/j.emc.2019.09.005
      • Account for 1/3 of all elbow fractures, and occur most commonly by a FOOSH
      • Displaced fractures can cause injury to the posterior interosseous nerve (a branch of the radial nerve), and manifests as inability to extend fingers
    • Distal humerus fractures[17]Hanlon DP, Mavrophilipos V. The Emergent Evaluation and Treatment of Elbow and Forearm Injuries. Emerg Med Clin North Am. 2020;38(1):81-102. doi:10.1016/j.emc.2019.09.005
      • Associated with high-energy impact or falls in geriatric/osteoporotic populations
      • Typically require surgery due to high-risk of ROM loss
    • The ultrasound-guided supraclavicular block (SCB) and the ultrasound-guided infraclavicular block (ICB) are nerve blocks with single-site injections of the brachial plexus above or below the clavicle to provide anesthesia to the upper limb including the distal humerus, elbow, forearm, and wrist.

Summary for regional anesthesia for the elbow

Link to Discussion of General Block Principles/Materials/Anesthetics & More

Anatomy

Link to Detailed Discussion of Upper Extremity Anatomy

Brachial plexus overview [18]Credit to NYSORA, Accessed 01/14/2023. … Continue reading

Innervation to the bones of the upper extremiteis[19]Credit to NYSORA, Accessed 01/30/2023. … Continue reading

  • The innervation of the elbow/forearm/wrist primarily comes from the three terminal branches of the brachial plexus (radial, median, ulnar). The musculocutaneous nerve provides innervation to the distal humerus.
    • The musculocutaneous nerve (C5-C7) is the terminal branch of the lateral cord from the brachial plexus. It’s motor fibers (musculo-) innervate the muscles of the anterior compartment of the arm including the biceps brachii, coracobrachialis, and brachialis, while its sensory fibers (-cutaneous) innervate the lateral forearm as the lateral antebrachial cutaneous nerve.[20]Desai SS, Varacallo M. Anatomy, Shoulder and Upper Limb, Musculocutaneous Nerve. In: StatPearls. StatPearls Publishing; 2020. Accessed February 2, 2021. http://www.ncbi.nlm.nih.gov/books/NBK534199/

Musculocutaneous nerve course and innervation[21]Credit to OrthoBullets, Accessed 01/30/2023. … Continue reading

    • The ulnar nerve (C8-T1) is a continuation of the medial cord. It provides motor innervation to the flexor carpi ulnaris and flexor digitorum profundus in the forearm, the hypothenar muscles, and additional muscles in the hand. It provides sensory innervation to the medial forearm, medial wrist, and 5th and medial half 4th digits.[22]Becker RE, Manna B. Anatomy, Shoulder and Upper Limb, Ulnar Nerve. In: StatPearls. StatPearls Publishing; 2020. Accessed February 2, 2021. http://www.ncbi.nlm.nih.gov/books/NBK499892/

Ulnar nerve anatomy [23]Becker RE, Manna B. Anatomy, Shoulder and Upper Limb, Ulnar Nerve. [Updated 2022 Jul 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: … Continue reading

    • The median nerve (C5-T1) is formed from the convergence of the lateral and medial cords. It provides motor innervation to the flexor muscles of the forearm and hand as well as sensory innervation to the palmar aspect of the thumb/index/middle/lateral half of the ring finger, as well as medial aspect of the forearm.[24]Murphy KA, Morrisonponce D. Anatomy, Shoulder and Upper Limb, Median Nerve. In: StatPearls. StatPearls Publishing; 2020. Accessed February 2, 2021. http://www.ncbi.nlm.nih.gov/books/NBK448084/

Median nerve anatomy  [25]Becker RE, Manna B. Anatomy, Shoulder and Upper Limb, Ulnar Nerve. [Updated 2022 Jul 25]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: … Continue reading

    • The radial nerve (C5-T1) is a continuation of the posterior cord to provide innervation of the posterior compartment of the arm and into the hand. It provides motor innervation to the triceps and all 12 muscles in the posterior forearm compartment (primarily wrist extensors). It provides cutaneous innervation to the distal posterior arm, posterior forearm, posterior aspects of the 1-3 digits and lateral half of 4th finger.[26]Glover NM, Murphy PB. Anatomy, Shoulder and Upper Limb, Radial Nerve. In: StatPearls. StatPearls Publishing; 2020. Accessed February 2, 2021. http://www.ncbi.nlm.nih.gov/books/NBK534840/

Radial nerve anatomy [27]Glover NM, Murphy PB. Anatomy, Shoulder and Upper Limb, Radial Nerve. [Updated 2022 Aug 29]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: … Continue reading

Supraclavicular Block

Overview
  • The ultrasound-guided supraclavicular block (SCB) is a regional-anesthesia nerve block which uses a single-site injection of the brachial plexus above the clavicle to provide anesthesia to the upper limb (with the exception of the medial aspect of the proximal arm. This is not the primary block for the shoulder (see ANATOMY below, see CH13a – Regional Anesthesia of the Shoulder).
  • The supraclavicular block is considered the “gold-standard” block for anesthesia of the distal arm.
  • The emergency medicine literature supporting the use of SCB consist of two papers by the same author group:
    • A case series published in 2007 highlighting the successful use of SCB in patients with upper extremity abscess, metacarpal fracture reduction, midshaft humerus fracture, and posterior elbow dislocation.[28]Stone MB, Price DD, Wang R. Ultrasound-guided supraclavicular block for the treatment of upper extremity fractures, dislocations, and abscesses in the ED. Am J Emerg Med. 2007;25(4):472-475. … Continue reading
    • A prospective observational trial in 2008 which found a decreased length of stay for SCB compared to procedural sedation. This small study (12 patients) employed the SCB for deltoid abscess, elbow dislocations, and humerus fractures. There were no adverse effects with SCB, and patient satisfaction was similar.[29]Stone MB, Wang R, Price DD. Ultrasound-guided supraclavicular brachial plexus nerve block vs procedural sedation for the treatment of upper extremity emergencies. Am J Emerg Med. 2008;26(6):706-710. … Continue reading
  • Suprascapular nerve and Shoulder Blockade
    • As described in most sources, the suprascapular nerve comes off the superior trunk (before the level of the supraclavicular block) and provides most of the innervation to the shoulder. This would make the SCB ineffective for shoulder joint blockade. However, there is anatomical variation of where the suprascapular nerve comes off. A cadaveric study found the nerve comes off the posterior division distal to the bifurcation of the trunk 61% of the time, and at the bifurcation itself 29%. Only 10% of cases came off proximal to the bifurcation point (off the upper trunk or directly from the C5 root).[30]Arad E, Li Z, Sitzman TJ, Agur AM, Clarke HM. Anatomic sites of origin of the suprascapular and lateral pectoral nerves within the brachial plexus. Plast Reconstr Surg. 2014;133(1):20e-27e. … Continue readingAnother cadaveric study found the suprascapular nerve came off the posterior division or bifurcation in 38% of specimens.[31]Leung S, Zlotolow DA, Kozin SH, Abzug JM. Surgical Anatomy of the Supraclavicular Brachial Plexus. J Bone Joint Surg Am. 2015;97(13):1067-1073. doi:10.2106/JBJS.N.00706Additionally, with SCB there is thought to be local spread of anesthetic proximally from the divisions between the anterior and middle scalene muscles in what’s been described as a “chimney” effect.[32]Cornish P. Supraclavicular block–new perspectives. Reg Anesth Pain Med. 2009;34(6):607-608. doi:10.1097/AAP.0b013e3181ada5afThis suggests that a SCB could be used for shoulder joint uses. Clinically, 2017 & 2019 systematic reviews and meta-analyses concluded there is comparable pain efficacy with SCB compared to ISB for shoulder surgery, along with fewer adverse effects of hemidiaphragmatic paresis and Horner’s syndrome with SCB.[33]Schubert A-K, Dinges H-C, Wulf H, Wiesmann T. Interscalene versus supraclavicular plexus block for the prevention of postoperative pain after shoulder surgery: A systematic review and meta-analysis. … Continue reading[34]Guo CW, Ma JX, Ma XL, et al. Supraclavicular block versus interscalene brachial plexus block for shoulder surgery: A meta-analysis of clinical control trials. Int J Surg Lond Engl. 2017;45:85-91. … Continue readingHowever, there is not enough conclusive data, and for now, interscalene remains the gold standard shoulder block.[35]Tran DQH, Elgueta MF, Aliste J, Finlayson RJ. Diaphragm-Sparing Nerve Blocks for Shoulder Surgery. Reg Anesth Pain Med. 2017;42(1):32-38. doi:10.1097/AAP.0000000000000529
  • Supraclavicular Block Specific Anatomy
    • The target of the SCB is the brachial plexus as it travels lateral and superficial to the subclavian artery. The artery and plexus emerge between the insertions of the anterior and middle scalene muscles, traveling superficial to the 1st rib, and approximately the midpoint of the clavicle.[36]Hadzic A. Ultrasound-Guided Supraclavicular Brachial Plexus Block. In: Hadzic’s Peripheral Nerve Blocks and Anatomy for Ultrasound-Guided Regional Anesthesia. McGraw-Hill Publishing; 2011. … Continue reading
    • The brachial plexus at this level is the distal trunks/proximal divisions. The roots of the brachial plexus (C5-T1) come together to form the following trunks:
      • Superior trunk: C5-C6 roots
      • Middle trunk: C7 roots
      • Inferior trunk: C8-T1 roots
    • Therefore, a supraclavicular block can provide motor and sensory blockade to the following major branches:
      • Musculocutaneous nerve (C5-C7): formed by lateral cord
      • Median nerve (C6-T1): formed by medial and lateral cords
      • Ulnar nerve (C8-T1): formed by medial nerve
      • Axillary nerve (C5-C6): formed by posterior cord
      • Radial nerve (C5-T1): posterior cord [37]Polcaro L, Charlick M, Daly DT. Anatomy, Head and Neck, Brachial Plexus. In: StatPearls. StatPearls Publishing; 2020. Accessed January 31, 2021. http://www.ncbi.nlm.nih.gov/books/NBK531473/
    • Notably, the medial skin of the upper arm is not anesthetized, as this comes from the intercostobrachial nerve from T2
  • Supraclavicular Block Specific Complications and Contraindications
    • Pneumothorax
      • Estimated incidence of clinically-symptomatic pneumothorax for US-guided SCB is about 0.06%.[38]Gauss A, Tugtekin I, Georgieff M, Dinse-Lambracht A, Keipke D, Gorsewski G. Incidence of clinically symptomatic pneumothorax in ultrasound-guided infraclavicular and supraclavicular brachial plexus … Continue reading
    • Hemidiaphragmatic paresis
      • Estimated 1-42% incidence[39]Schubert A-K, Dinges H-C, Wulf H, Wiesmann T. Interscalene versus supraclavicular plexus block for the prevention of postoperative pain after shoulder surgery: A systematic review and meta-analysis. … Continue reading[40]Perlas A, Lobo G, Lo N, Brull R, Chan VWS, Karkhanis R. Ultrasound-guided supraclavicular block: outcome of 510 consecutive cases. Reg Anesth Pain Med. 2009;34(2):171-176. … Continue reading
    • Brachial plexopathy
      • Estimated 0.4% incidence[41]Perlas A, Lobo G, Lo N, Brull R, Chan VWS, Karkhanis R. Ultrasound-guided supraclavicular block: outcome of 510 consecutive cases. Reg Anesth Pain Med. 2009;34(2):171-176. … Continue reading
    • Horner syndrome
      • Estimated 1-8% incidence[42]Schubert A-K, Dinges H-C, Wulf H, Wiesmann T. Interscalene versus supraclavicular plexus block for the prevention of postoperative pain after shoulder surgery: A systematic review and meta-analysis. … Continue reading[43]Perlas A, Lobo G, Lo N, Brull R, Chan VWS, Karkhanis R. Ultrasound-guided supraclavicular block: outcome of 510 consecutive cases. Reg Anesth Pain Med. 2009;34(2):171-176. … Continue reading
    • Puncture of vascular structure
      • Estimated 0.4% incidence[44]Perlas A, Lobo G, Lo N, Brull R, Chan VWS, Karkhanis R. Ultrasound-guided supraclavicular block: outcome of 510 consecutive cases. Reg Anesth Pain Med. 2009;34(2):171-176. … Continue reading
    • Diaphragmatic Paresis
      • While much less common than interscalene block, local anesthesia spread can lead to diaphragmatic paresis. Exert caution in patients with severe pulmonary disease.[45]D’Souza RS, Johnson RL. Supraclavicular Block. In: StatPearls. StatPearls Publishing; 2020. Accessed February 14, 2021. http://www.ncbi.nlm.nih.gov/books/NBK519056/

Supraclavicular nerve block distribution [46] Credit to NYSORA, Accessed 01/30/2023. https://www.nysora.com/techniques/upper-extremity/intescalene/ultrasound-guided-interscalene-brachial-plexus-block/

Ultrasound Anatomy
  • Patient positioning: The patient can be positioned supine or semi-sitting with the head of bed up. The head should be turned towards the contralateral side. 
  • Anatomic landmark: Start scanning just above the clavicle at its midpoint, with the ultrasound probe parallel to the clavicle. Tilt the probe caudally, as if to scan in the direction of the lungs. This will be a transverse orientation relative to the BP and subclavian artery. 
  • Scanning protocol:
    • Identify the subclavian artery (SA). The BP is seen laterally and superficial to the artery, as a collection of hypoechoic oval structures (the classic description of a “bundle of grapes”. You may see a hyperechoic fascial sheath surrounding the BP. 
    • Identify the first rib. This will be hyperechoic, linear, and will cast an acoustic shadow deep to the rib. 
    • Identify the hyperechoic lung pleura. This can be visualized lateral and medial to the first rib. Confirm lung “sliding” with respirations. 
    • Lateral to the BP and SA, identify the middle scalene muscle. You may also see the anterior scalene muscle medial to the SA. The sternocleidomastoid muscle will be the most superficial muscle on the medial aspect. 
    • Apply color doppler to evaluate for vasculature. Vessels can mimic nerve bundles (circular and hypoechoic). There’s a high prevalence of smaller vessels traveling directly adjacent or even interposed with the BP in the interscalene and supraclavicular areas.[47]Muhly WT, Orebaugh SL. Sonoanatomy of the vasculature at the supraclavicular and interscalene regions relevant for brachial plexus block. Acta Anaesthesiol Scand. 2011;55(10):1247-1253. … Continue readingIdentification of vasculature can prevent puncture and may prevent complications including hematoma, incomplete analgesia, and local-anesthetic systemic toxicity.[48]Hahn C, Nagdev A. Color Doppler ultrasound-guided supraclavicular brachial plexus block to prevent vascular injection. West J Emerg Med. 2014;15(6):703-705. doi:10.5811/westjem.2014.5.21716[49]Kohli S, Yadav N, Prasad A, Banerjee SS. Anatomic variation of subclavian artery visualized on ultrasound-guided supraclavicular brachial plexus block. Case Rep Med. 2014;2014:394920. … Continue reading
  •  

Sit the patient either completely supine or with the head of the bed slightly elevated. The author prefers head of bed elevated with the operator standing behind the head of the bed. 

Start with US transducer just above the midpoint of the clavicle and parallel to the clavicle. 

Identify the subclavian artery. The brachial plexus is seen laterally and superficial, as a “bundle of grapes”. 

Apply color doppler to evaluate for vasculature. The brachial plexus bundle of grapes should not “light up”. 

Approach
  • Document a neurovascular exam. All the surrounding nerves of the elbow are at risk of injury with elbow dislocation.[50]Layson J, Best BJ. Elbow Dislocation. In: StatPearls. StatPearls Publishing; 2020. Accessed February 7, 2021. http://www.ncbi.nlm.nih.gov/books/NBK549817/
    • Median nerve – test branch of anterior interosseus nerve with “OK” sign. Test sensation to light touch over palmar 2nd digit. Median nerve deficits should raise suspicion for associated brachial artery injury given their proximity to each other.[51]Hanlon DP, Mavrophilipos V. The Emergent Evaluation and Treatment of Elbow and Forearm Injuries. Emerg Med Clin North Am. 2020;38(1):81-102. doi:10.1016/j.emc.2019.09.005
    • Ulnar nerve – abduct and adduct fingers. Test sensation to light touch over palmar 5th digit. There is a 8-21% risk of ulnar injury with posterior elbow dislocation.[52]Hanlon DP, Mavrophilipos V. The Emergent Evaluation and Treatment of Elbow and Forearm Injuries. Emerg Med Clin North Am. 2020;38(1):81-102. doi:10.1016/j.emc.2019.09.005
    • Radial nerve – wrist extension and thumb extension. Test sensation to light touch over dorsal 1st digit.
  • Use the ultrasound to identify target BP and mark the site of your predicted needle entry point (Tip – use a ear/nasal speculum to indent the skin)
  • Prepare equipment, prep skin and site, cover ultrasound probe with sterile-cover. Connect extension tubing to syringe. Prime the tubing with normal saline. Attach needle to opposite end of extension tubing. Hand off syringe to assistant, and use the ultrasound to identify the anatomy again.
  • [OPTIONAL] Inject 1-2cc of anesthetic in a wheal using a 27g to decrease discomfort from the larger spinal needle
  • Insert the needle from lateral to medial, in-plane with the ultrasound. Aim the needle tip towards the brachial plexus, away from the subclavian artery. After aspiration to ensure no blood, inject 1-2 mL of anesthetic to confirm needle placement. Inject anesthetic until the brachial plexus pushes away from the needle. Then reposition the needle as needed to continue to inject anesthetic around the nerve.  Do NOT inject against resistance. This suggests needle placement within the nerve.
  • Successful block can occur with injection of anesthetic outside the paraneural BP sheath. While time to onset is slower and duration is less, for the emergency medicine physician there is likely less risk injecting outside the sheath than in.[53]Sivashanmugam T, Ray S, Ravishankar M, Jaya V, Selvam E, Karmakar MK. Randomized Comparison of Extrafascial Versus Subfascial Injection of Local Anesthetic During Ultrasound-Guided Supraclavicular … Continue reading
  • Confirm onset of block with sensory loss in the distal hand, again testing median, ulnar, and radial distributions.

Entry needle position for the supraclavicular block

Video of US-guided supraclavicular nerve block

Infraclavicular Block

Overview
  • The ultrasound-guided infraclavicular block (ICB) is a regional-anesthesia nerve block which uses a single-site injection of the brachial plexus below the clavicle to provide anesthesia to the upper limb (with the exception of the medial aspect of the proximal arm and the shoulder joint).
  • Infraclavicular block vs Supraclavicular block
    • There are no published trials comparing the efficacy of SCB vs ICB in the emergency department
    • In the operating room, ICB has been shown to be as effective as SCB for analgesia of the distal arm. They have equivalent time to onset, success rate and duration of the block.[54]Chin KJ, Alakkad H, Adhikary SD, Singh M. Infraclavicular brachial plexus block for regional anaesthesia of the lower arm. Cochrane Database Syst Rev. 2013;(8):CD005487. … Continue reading[55]Koscielniak-Nielsen ZJ, Frederiksen BS, Rasmussen H, Hesselbjerg L. A comparison of ultrasound-guided supraclavicular and infraclavicular blocks for upper extremity surgery. Acta Anaesthesiol Scand. … Continue reading[56]Arcand G, Williams SR, Chouinard P, et al. Ultrasound-guided infraclavicular versus supraclavicular block. Anesth Analg. 2005;101(3):886-890, table of contents. doi:10.1213/01.ANE.0000159168.69934.CC[57]De José María B, Banús E, Navarro Egea M, Serrano S, Perelló M, Mabrok M. Ultrasound-guided supraclavicular vs infraclavicular brachial plexus blocks in children. Paediatr Anaesth. … Continue reading[58]Park S-K, Lee S-Y, Kim WH, Park H-S, Lim Y-J, Bahk J-H. Comparison of Supraclavicular and Infraclavicular Brachial Plexus Block: A Systemic Review of Randomized Controlled Trials. Anesth Analg. … Continue reading[59]Bharti N, Bhardawaj N, Wig J. Comparison of ultrasound-guided supraclavicular, infraclavicular and below-C6 interscalene brachial plexus block for upper limb surgery: a randomised, observer-blinded … Continue reading
    • The major differences between the ICB and SCB include:
      • Risk of inadvertent lung/pleural puncture is lower with ICB as the lung is not in the path of the needle.[60]Chin KJ, Alakkad H, Adhikary SD, Singh M. Infraclavicular brachial plexus block for regional anaesthesia of the lower arm. Cochrane Database Syst Rev. 2013;(8):CD005487. … Continue reading
      • ICB may provide more reliable blockade of the ulnar nerve; however, is more likely to miss blocking the radial nerve and the axillary nerve. The radial nerve is likely missed as it arises from the posterior cord, which is the deepest and therefore farthest cord from needle entry.[61]Neal JM, Gerancher JC, Hebl JR, et al. Upper extremity regional anesthesia: essentials of our current understanding, 2008. Reg Anesth Pain Med. 2009;34(2):134-170. doi:10.1097/AAP.0b013e31819624eb[62]Chin KJ, Alakkad H, Adhikary SD, Singh M. Infraclavicular brachial plexus block for regional anaesthesia of the lower arm. Cochrane Database Syst Rev. 2013;(8):CD005487. … Continue reading[63]Koscielniak-Nielsen ZJ, Frederiksen BS, Rasmussen H, Hesselbjerg L. A comparison of ultrasound-guided supraclavicular and infraclavicular blocks for upper extremity surgery. Acta Anaesthesiol Scand. … Continue reading[64]Park S-K, Lee S-Y, Kim WH, Park H-S, Lim Y-J, Bahk J-H. Comparison of Supraclavicular and Infraclavicular Brachial Plexus Block: A Systemic Review of Randomized Controlled Trials. Anesth Analg. … Continue reading
      • ICB avoids other neurovascular structures in the neck[65]Chin KJ, Alakkad H, Adhikary SD, Singh M. Infraclavicular brachial plexus block for regional anaesthesia of the lower arm. Cochrane Database Syst Rev. 2013;(8):CD005487. … Continue reading
      • Although less common than interscalene blocks, hemidiaphragmatic paralysis has a higher incidence in SCB (34%), compared to ICB (4%)[66]Petrar SD, Seltenrich ME, Head SJ, Schwarz SKW. Hemidiaphragmatic paralysis following ultrasound-guided supraclavicular versus infraclavicular brachial plexus blockade: a randomized clinical trial. … Continue reading
  • The emergency medicine literature supporting the use of ICB consists of:
    • 2015 & 2017 case reports of ICB for reduction of posterior elbow dislocation[67]Heflin T, Ahern T, Herring A. Ultrasound-guided infraclavicular brachial plexus block for emergency management of a posterior elbow dislocation. Am J Emerg Med. 2015;33(9):1324.e1-4. … Continue reading[68]Akay S, Eksert S, Kaya M, Keklikci K, Kantemir A. Case Report: Ultrasound-Guided Infraclavicular Brachial Plexus Block for a Case with Posterior Elbow Dislocation. J Emerg Med. 2017;53(2):232-235. … Continue reading
    • A 2017 description of the RAPTIR technique along with several cases[69]Luftig J, Mantuani D, Herring AA, Nagdev A. Ultrasound-guided retroclavicular approach infraclavicular brachial plexus block for upper extremity emergency procedures. Am J Emerg Med. … Continue reading
  • Infraclavicular Block Specific Complications and Considerations
    • Pneumothorax
      • Estimated incidence of clinically-symptomatic pneumothorax for US-guided ICB is about 0.07%.[70]Gauss A, Tugtekin I, Georgieff M, Dinse-Lambracht A, Keipke D, Gorsewski G. Incidence of clinically symptomatic pneumothorax in ultrasound-guided infraclavicular and supraclavicular brachial plexus … Continue reading
    • Brachial plexopathy
      • Estimated incidence 0.8%[71]Lecours M, Lévesque S, Dion N, Nadeau M-J, Dionne A, Turgeon AF. Complications of single-injection ultrasound-guided infraclavicular block: a cohort study. Can J Anaesth J Can Anesth. … Continue reading
    • Horner syndrome
      • Estimated incidence 1.5%

Infraclavicular nerve block distribution [72]Credit to NYSORA, Accessed 01/31/2023. … Continue reading

Ultrasound Anatomy
  • Anatomy
    • The target of the ICB is the brachial plexus distal to the clavicle as the lateral, posterior, and medial cords of the brachial plexus travel next to the subclavian artery which has become the axillary artery. The cords are named for their position relative to the axillary artery.[73]Williams LM, Singh K, Dua A, Singh A, Cummings A. Infraclavicular Nerve Block. In: StatPearls. StatPearls Publishing; 2020. Accessed February 14, 2021. http://www.ncbi.nlm.nih.gov/books/NBK537016/ The cords and axillary vessels lie slightly medial to the coracoid process, and deep to the pectoralis major and minor muscles.[74]Williams LM, Singh K, Dua A, Singh A, Cummings A. Infraclavicular Nerve Block. In: StatPearls. StatPearls Publishing; 2020. Accessed February 14, 2021. http://www.ncbi.nlm.nih.gov/books/NBK537016/
    • The cords contain the following root contributions:[75]Polcaro L, Charlick M, Daly DT. Anatomy, Head and Neck, Brachial Plexus. In: StatPearls. StatPearls Publishing; 2020. Accessed January 31, 2021. http://www.ncbi.nlm.nih.gov/books/NBK531473/
      • Lateral cord: C5-C7
      • Medial cord: C8-T1
      • Posterior cord: C5-T1
    • The cords give rise to the 5 major terminal branches of the limb as well as 7 other branches.[76]Polcaro L, Charlick M, Daly DT. Anatomy, Head and Neck, Brachial Plexus. In: StatPearls. StatPearls Publishing; 2020. Accessed January 31, 2021. http://www.ncbi.nlm.nih.gov/books/NBK531473/Therefore, a supraclavicular block can provide motor and sensory blockade to the following major branches:
      • Musculocutaneous nerve (C5-C7): formed by lateral cord
      • Median nerve (C6-T1): formed by medial and lateral cords
      • Ulnar nerve (C8-T1): formed by medial cord
      • Axillary nerve (C5-C6): formed by posterior cord
      • Radial nerve (C5-T1): posterior cord
    • Notably, the medial skin of the upper arm is not anesthetized, as this comes from the intercostobrachial nerve from T2. Additionally, anesthesia to the shoulder joint is not provided (from the suprascapular nerve, see CH13a – Regional Anesthesia of the Shoulder).
  • There are several variations on the approach of the ICB – coracoid approach, lateral sagittal approach, vertical approach, and retroclavicular approach. The coracoid approach is the most common in North America, because of the theoretically reduced risk of pneumothorax.[77]Neal JM, Gerancher JC, Hebl JR, et al. Upper extremity regional anesthesia: essentials of our current understanding, 2008. Reg Anesth Pain Med. 2009;34(2):134-170. doi:10.1097/AAP.0b013e31819624ebThe retroclavicular approach (RAPTIR) is gaining popularity because of its improved needle visualization. This text will review the coracoid approach and the RAPTIR.
Coracoid Approach
  • Patient positioning:
    • The patient should be supine with the head turned towards the contralateral side. 
    • Abduct the arm to 90° and keep the elbow flexed. This position reduces the depth from the skin to the plexus.
    • Bed height should be appropriate height for operator comfort. Operator is standing on ipsilateral side of the patient. 
    • Ultrasound machine situated on opposite side of bed (allows easy visualization of screen with in-plane technique)
  • Anatomic landmarks:
    • Palpate the coracoid process of the scapula. This is the bony prominence on the medial aspect of the shoulder. Place the ultrasound probe medial to the coracoid process inferior to the clavicle. The transducer is positioned in a somewhat oblique position, with the inferior end of the probe angled towards the opposite hip. 
  • Scanning protocol:
    • Identify the pectoralis major and the pectoralis minor and their respective fascia. This is important because our area of interest is underneath the fascia of the pectoralis minor. 
    • Identify the axillary artery (AA). The AA is deep to the pectoralis major and minor muscles. This is typically at a depth of 3 to 5 cm.
    • The three cords of the BP surround the AA. The cords are named for their position relative to the artery. With the left side of the screen corresponding to cephalad, the lateral cord is approximately at 9 o’clock, posterior cord at 7 o’clock, and medial cord at 5 o’clock. However, there is considerable variation in these positions.
    • Identify the axillary vein which is most often inferior to the AA, and is compressible. 
    • Depending on the depth, lung pleura may be visualized. Confirm lung “sliding” with respirations
    • Apply color doppler to evaluate for vasculature. Vessels can mimic nerve bundles (circular and hypoechoic). There’s a high prevalence of smaller vessels traveling directly adjacent or even interposed with the BP in the interscalene and supraclavicular areas.[78]Muhly WT, Orebaugh SL. Sonoanatomy of the vasculature at the supraclavicular and interscalene regions relevant for brachial plexus block. Acta Anaesthesiol Scand. 2011;55(10):1247-1253. … Continue readingIdentification of vasculature can prevent puncture and may prevent complications including hematoma, incomplete analgesia, and local-anesthetic systemic toxicity.[79]Hahn C, Nagdev A. Color Doppler ultrasound-guided supraclavicular brachial plexus block to prevent vascular injection. West J Emerg Med. 2014;15(6):703-705. doi:10.5811/westjem.2014.5.21716[80]Kohli S, Yadav N, Prasad A, Banerjee SS. Anatomic variation of subclavian artery visualized on ultrasound-guided supraclavicular brachial plexus block. Case Rep Med. 2014;2014:394920. … Continue reading [81]Sono-anatomy and Patient Positioning. Hadzic A. Ultrasound-Guided Infraclavicular Brachial Plexus Block. In: Hadzic’s Peripheral Nerve Blocks and Anatomy for Ultrasound-Guided Regional Anesthesia. … Continue reading

Sit the patient either completely supine or with the head of the bed slightly elevated. The author prefers head of bed elevated with the operator standing behind the head of the bed. 

Place the ultrasound probe medial to the coracoid process inferior to the clavicle. The transducer is positioned in a somewhat oblique position, with the inferior end of the probe angled towards the opposite hip. 

Identify the pectoralis major and minor muscles. Identify the axillary artery deep to the muscles, about 3-5cm. The three cords of the brachial plexus surround the axillary artery. 

Apply color doppler to evaluate for vasculature. 

Retroclavicular Approach (RAPTIR)
  • The RAPTIR technique for ICB provides improved needle visualization. The coracoid approach requires a relatively steep needle angle to reach the BP. The steep angle produces relatively poor needle visualization. With the RAPTIR approach, the needle is passed posteriorly to the clavice (retro-), which produces a very shallow needle angle allowing better sound reflection and needle visualization. [82]Luftig J, Mantuani D, Herring AA, Nagdev A. Ultrasound-guided retroclavicular approach infraclavicular brachial plexus block for upper extremity emergency procedures. Am J Emerg Med. … Continue reading
    • Evidence: The retroclavicular approach has been shown in anesthesia literature to be equally as effective compared to SCB.[83]Grape S, Pawa A, Weber E, Albrecht E. Retroclavicular vs supraclavicular brachial plexus block for distal upper limb surgery: a randomised, controlled, single-blinded trial. Br J Anaesth. … Continue readingWhen compared to the coracoid approach-ICB, RAPTIR has been shown to have better needle visibility, faster time to needle placement, and less paresthesia.[84]Kavrut Ozturk N, Kavakli AS. Comparison of the coracoid and retroclavicular approaches for ultrasound-guided infraclavicular brachial plexus block. J Anesth. 2017;31(4):572-578. … Continue reading[85]Blanco AFG, Laferrière-Langlois P, Jessop D, et al. Retroclavicular vs Infraclavicular block for brachial plexus anesthesia: a multi-centric randomized trial. BMC Anesthesiol. 2019;19(1):193. … Continue reading
  • Patient positioning:
    • The patient is in a supine position or head-of-bed elevated with their head to the contralateral side. The operator stands at the head of the bed looking towards the patient’s feet, with the ultrasound on the ipsilateral side in the direct line-of-site of the operator. Alternatively, the patient may be lying supine with the operator at the head of the bed. 
  • Anatomic landmarks:
    • Follow the same steps as the coracoid approach. Palpate the coracoid process of the scapula. This is the bony prominence on the medial aspect of the shoulder. Place the ultrasound probe medial to the coracoid process inferior to the clavicle.
  • Scanning protocol:
    • Obtain the same ultrasound image as found with the coracoid approach. Bring the transducer so that it is touching the clavicle with the clavicle at the end of the screen. Angle the inferior portion of the transducer towards the ipsilateral axilla. This way the angle of the needle will be away from the lungs. Identify the BP and SA as before. 

The patient is in a supine position or head-of-bed elevated with their head to the contralateral side. The operator stands at the head of the bed looking towards the patient’s feet, with the ultrasound on the ipsilateral side in the direct line-of-site of the operator. Alternatively, the patient may be lying supine with the operator at the head of the bed. 

Place the ultrasound probe medial to the coracoid process inferior to the clavicle. The transducer is positioned in a somewhat oblique position, with the inferior end of the probe angled towards the opposite hip. 

Identify the pectoralis major and minor muscles. Identify the axillary artery deep to the muscles, about 3-5cm. The three cords of the brachial plexus surround the axillary artery. 

Apply color doppler to evaluate for vasculature. 

Approach
Coracoid Approach
  • Document a neurovascular exam. All the surrounding nerves of the elbow are at risk of injury with elbow dislocation.[86]Layson J, Best BJ. Elbow Dislocation. In: StatPearls. StatPearls Publishing; 2020. Accessed February 7, 2021. http://www.ncbi.nlm.nih.gov/books/NBK549817/
    • Median nerve – test branch of anterior interosseus nerve with “OK” sign. Test sensation to light touch over palmar 2nd digit. Median nerve deficits should raise suspicion for associated brachial artery injury given their proximity to each other.[87]Hanlon DP, Mavrophilipos V. The Emergent Evaluation and Treatment of Elbow and Forearm Injuries. Emerg Med Clin North Am. 2020;38(1):81-102. doi:10.1016/j.emc.2019.09.005
    • Ulnar nerve – abduct and adduct fingers. Test sensation to light touch over palmar 5th digit. There is a 8-21% risk of ulnar injury with posterior elbow dislocation.[88]Hanlon DP, Mavrophilipos V. The Emergent Evaluation and Treatment of Elbow and Forearm Injuries. Emerg Med Clin North Am. 2020;38(1):81-102. doi:10.1016/j.emc.2019.09.005
    • Radial nerve – wrist extension and thumb extension. Test sensation to light touch over dorsal 1st digit
  • Block specific supplies
    • 22g 3.5 in spinal needle (or similar size, spinal needle preferred)
    • Local anesthetic + appropriate size syringe
      • 20-30mL of anesthetic is appropriate for most adults.[89]Hadzic A. Ultrasound-Guided Infraclavicular Brachial Plexus Block. In: Hadzic’s Peripheral Nerve Blocks and Anatomy for Ultrasound-Guided Regional Anesthesia. McGraw-Hill Publishing; 2011. … Continue reading
      • This may be treated like a plane block with higher volumes. Due to concern for local anesthetic toxicity, 20 mL of lidocaine can be diluted with 20 mL of normal saline. The extra volume helps with local anesthetic spread.
  • Use the ultrasound to identify target BP and mark the site of your predicted needle entry point
  • Prepare equipment, prep skin and site, cover ultrasound probe with sterile-cover. Connect extension tubing to syringe. Prime the tubing with normal saline. Attach needle to opposite end of extension tubing. Hand off syringe to assistant, and use the ultrasound to identify the anatomy again.
  • [OPTIONAL] Inject 1-2cc of anesthetic in a wheal using a 27g to decrease discomfort from the larger spinal needle
  • Insert the needle from lateral to medial, in-plane with the ultrasound. Aim the needle tip towards the brachial plexus, away from the subclavian artery. After aspiration to ensure no blood, inject 1-2 mL of anesthetic to confirm needle placement.
  • Inject anesthetic until the brachial plexus pushes away from the needle. Then reposition the needle as needed to continue to inject anesthetic around the nerve.  Do NOT inject against resistance. This suggests needle placement within the nerve.

Entry needle position for coracoid approach for supraclavicular nerve block

Video of US-guided coracoid approach for supracavicular nerve block

Retroclavicular Approach (RAPTIR)
  • Document neuro exam as above in coracoid approach
  • Block specific supplies
    • 22g 3.5 in spinal needle (or similar size, spinal needle preferred)
    • Local anesthetic + appropriate size syringe
      • 20-30mL of anesthetic is appropriate for most adults.[90]Hadzic A. Ultrasound-Guided Infraclavicular Brachial Plexus Block. In: Hadzic’s Peripheral Nerve Blocks and Anatomy for Ultrasound-Guided Regional Anesthesia. McGraw-Hill Publishing; 2011. … Continue reading
      • This may be treated like a plane block with higher volumes. Due to concern for local anesthetic toxicity, 20 mL of lidocaine can be diluted with 20 mL of normal saline. The extra volume helps with local anesthetic spread.
  • Use the ultrasound to identify target BP and mark the site of your predicted needle entry point
  • Prepare equipment, prep skin and site, cover ultrasound probe with sterile-cover. Connect extension tubing to syringe. Prime the tubing with normal saline. Attach needle to opposite end of extension tubing. Hand off syringe to assistant, and use the ultrasound to identify the anatomy again.
  • [OPTIONAL] Inject 1-2cc of anesthetic in a wheal using a 27g to decrease discomfort from the larger spinal needle
  • Insert the needle in-plane with the transducer at a position CEPHALAD to the clavicle. The needle will have to be inserted about 2cm cephalad to the clavicle to get underneath the clavicle. Advance the needle underneath the clavicle, which will be a 3cm “blind zone.” Fan and toggle the transducer to identify the needle tip once it has come out from under the clavicle. Once identified, advance the needle towards the BP. Once in position, aspirate and inject as with the coracoid approach. [91]Luftig J, Mantuani D, Herring AA, Nagdev A. Ultrasound-guided retroclavicular approach infraclavicular brachial plexus block for upper extremity emergency procedures. Am J Emerg Med. … Continue reading

Entry needle position for RAPTIR block

Video of US-guided RAPTIR nerve block

Pearls & Pitfalls

Link to Discussion of General Pearls and Pitfalls
  • Pearls
    • Most emergency departments do not have a standard block kit or a block cart. Consider creating a regional anesthesia cart in your emergency department which houses all these supplies for easy set-up
    • For departments without a block cart or kit, use a standard laceration tray – this will contain sterile towels, syringe, 18g needle to draw up anesthetic
    • Instead of using a marking pen to mark your target, use a ear/nasal speculum to indent the skin. This stays visible after sterilization
    • If you’re having difficulty identifying your needle tip, use “hydrolocation”. Inject a tiny amount of fluid and dissect through tissue surrounding the needle. Soundwaves are less attenuated through the fluid than tissue, enhancing needle visualization. This is known as “acoustic enhancement” or “through transmission enhancement”.
    • Using an in-plane technique, the shallower the angle of the needle, the better needle visualization as more sound waves bounce-back to the ultrasound probe. It is useful to take a shallow angle, identify the needle tip, and then make adjustments to the angle as needed. 
    • An easy rule of thumb is to combine 15cc of your preferred local anesthetic (lidocaine 1% of bupivacaine 1% or 0.5%) with 15cc of normal saline. This allows you to use a single 30cc syringe, and does not require you to weigh the patient and calculate max dose; 15cc is likely well below the toxic threshold for most adult patients. 
    • If your department has the ability to save and store ultrasound images, take a screenshot or video of your needle in position while injecting fluid. This provides documentation for billing purposes as well medicolegal proof you did not have needle placement in undesired structures
  • Pitfalls
    • DO NOT inject against resistance. This suggests the needle tip is in an undesired location, such as intraneural. 
    • DO NOT attempt needle placement without first using color doppler to identify vascular structures.
    • DO NOT attempt SCB or ICB without first performing and documenting a neurovascular exam. Perform a post-procedure neurovascular exam as well. 
    • Be cognizant of local anesthetic systemic toxicity (LAST). This text does not cover it, but you should be aware of signs and symptoms as well as have a plan for treatment including access to intralipids.

References[+]