Brachial Plexus block pt.2

Brachial plexus block

There are many approaches to brachial plexus block:

1. Supraclavicular block
2. Infraclavicular block
3. Interscalene block
4. Axillary block

Supraclavicular block

Clinical implication
• Supraclavicular brachial plexus block is used for surgical procedures of the upper limb from midhumeral level to the hand
• The brachial plexus is at the level of the trunk so the blockade here blocks all the branches of the brachial plexus
• It provides dense anesthesia to the upper arm, elbow and forearm
Procedure
• Patient is placed in the supine position with head turned towards the opposite side
• Posterior border of sternocleidomastoid muscle is palpated at C6 level and fingers are rolled over the anterior scalene muscle until they lie in interscalene groove
• Then, fingers are moved laterally down the interscalene groove until they are approximately one centimeter from the mid clavicle
• 22 gauge, 5 cm insulated needle is inserted at this point and 30-40 ml of local anesthetic is injected to block the brachial plexus
• The brachial plexus is deep at this site and is often reached at 2-4 cm
• A nerve stimulator is attached to the needle and is set at 1-1.2 mA. Proper needle placement is indicated by flexion or extension of the digits at 0.5 mA or less.
o Aspiration of blood indicates subclavian artery penetration, needle is too medial
o Stimulation of musculocutaneous nerve (biceps contraction) indicates needle is too lateral
o Pectoralis muscle contraction indicates needle is anterior
o Scapular movement indicates needle is posterior to the plexus

Dexmedetomidine added as an adjuvant to bupivacaine for supraclaviculat brachial plexus block shortens the onset time and prolongs the duration of sensory and motor blocks and duration of analgesia.

Source: Agarwal S, Aggarwal R, Gupta P. Dexmedetomidine prolongs the effect of bupivacaine in supraclavicular brachial plexus block. J Anesthesiol Clin Pharmacol. 2014 Jan; 30(1): 36-40.

Higher doses of clonidine in brachial plexus block hastens the onset, prolongs the duration of sensorimotor blockade and postoperative analgesia without significant hemodynamic alterations. It also causes more sedation.
Source: Kohli S, Kaur M, Sahoo S, Vajifdar H, Kohli P. Brachial plexus block: comparison of two different doses of clonidine added to bupivacaine. J Anesthesiol Clin Pharmacol 2013 Oct; 29(4): 491-5.

Addition of dexamethasone to 1.5% lidocaine with adrenaline in supraclavicular brachial plexus block speeds the onset and the duration of sensory and motor blockade.
Source: Biradar PA, Kaimar P, Gopalakrishna K. Effect of dexamethasone added to lidocaine in supraclavicular brachial plexus block: A prospective, randomised, double-blind study. Indian J Anaesth. 2013 March; 57(2): 180-4.

Low dose ropivacaine is clinically acceptable for brachial plexus block under general anesthesia.
Source: Iwata T, Nakahashi K, Inoue S, Furuya H. Low dose of ropivacaine for supraclavicular brachial plexus block combined with general anesthesia for successful postoperative analgesia: A case series. Saudi J Anaesth. 2013 Jan; 7(1): 37-9.

The ED₅₀ dose of bupivacaine for supraclavicular block is not dependent on the concentration. Lowering the concentration or the strength of the local anaesthetic leads to an increase in the volume required for successful block.
Source: Gupta PK, Hopkins PM. Effect of concentration of local anaesthetic solution on the ED₅₀ of bupivacaine for supraclavicular brachial plexus block. Br J Anaesth. 2013 Aug;111(2):293-6.

Complications

•Pneumothorax: the onset of symptom is delayed and may take 24 hours. There is sudden onset of cough and shortness of breath
• Phrenic nerve block causes diaphragmatic hemiparesis with minimal accompanying reduction in forced vital capacity (FVC)
• Horner syndrome
• Neuropathy
• Patient with renal failure have risk of respiratory failure following supraclavicular brachial plexus block
Source: Afonso A, Beilin Y. Respiratory arrest in patients undergoing arteriovenous graft placement with supraclavicular brachial plexus block: a case series. J Clin Anesth. 2013 Jun; 25(4): 321-3.
• A high incidence of postoperative neurological symptoms are observed following ultrasound guided interscalene and supraclavicular anesthetic blocks
Source: Bilbao Ares A, Sabate A, Porteiro L, Ibanez B, Koo M, Pi A. Neurological complications associated with ultrasound guided interscalene and supraclavicular block in elective surgery of the shoulder and arm. Prospective observational study in a university hospital. Rev Esp Anesthesiol Reanim. 2013 Aug-Sep;60(7):384-91.

Ultrasound guided supraclavicular brachial plexus block

• High frequency (5-12 MHz), linear probe is placed in the supraclavicular fossa, oriented perpendicular to the subclavian artery with the probe indicator oriented towards the clavicle for a left sided block and the trapezius for a right sided block
• Plexus is configured as trunks or divisions and is typically located lateral and slightly superior to the subclavian artery at depth of 2-4 cm
• The coronal oblique plane gives transverse view of the brachial plexus while cross sectional (axial) view displays nerves as hypoechoic circles with hyperechoic rings (bundle of grapes)
• Needle is inserted at the lateral end of ultrasound probe and advanced parallel to the ultrasound beam until it approaches the brachial plexus
• The spread of local anesthetic is observed during the injection, allowing real time readjustment of the needle tip position if the spread is not appropriate
• DONUT sign is created by spread of local anesthetic surrounding the nerves, indicates that anesthetic is properly distributed
Ultrasound guided supraclavicular brachial plexus block reduces the probability of major complications (pneumothorax, Horner’s syndrome, phrenic nerve palsy)
Source: Sadowski M, Tulaza B, Lysenko L. Renaissance of supraclavicular brachial plexus block. Anesthesiol Intensive Ther. 2014 Jan-Mar; 46(1): 37-41.

The risk of pneumothorax is 0.4 per 1000 after ultrasound guided supraclavicular block.
Source: Abell DJ, Barrington MJ. Pneumothorax after ultrasound guided supraclavicular block: presenting feature, risk and related training. Reg Anesth Pain Med 2014 Mar-Apr; 39(2): 164-7.

30 ml of local anesthetic volume is sufficient for ultrasound guided supraclavicular block.
Source: Jeon DG, Kim SK, Kang BJ, Kwon MA, Song JG, Jeon SM. Comparison of ultrasound guided supraclavicular block according t various volumes of local anesthetic. Koreon J Anesthesiol. 2013 Jun 64(6): 494-9.

Ultrasound-guided supraclavicular brachial plexus block enhance the degree of sympathetic block of upper extremity, especially of ulnar artery and increase the blood flow of ulnar artery compared with nerve stimulator.
Source: Li T, Ye XH, Nan Y, Shi T, Ye QG, Ma JF, Li J.

Comparison of ultrasound and nerve stimulation techniques for brachial plexus block for regional hemodynamic changes of upper extremity. Zhonghua Yi Xue Za Zhi. 2013 Jan 15;93(3):187-90.

A reduced minimum effective anesthetic volume for ultrasound-guided supraclavicular block in elderly patients. Additionally, smaller cross-sectional surface area of brachial plexus in the supraclavicular region was observed.
Source: Pavicic Saric J, Vidjak V, Tomulic K, Zenko J.

Effects of age on minimum effective volume of local anesthetic for ultrasound-guided supraclavicular brachial plexus block. Acta Anaesthesiol Scand. 2013 Jul;57(6):761-6.

Upper limb regional anesthesia has gained in popularity because of its effectiveness and the safety profile associated with ultrasound-guided techniques.

Source: Nadeau MJ, Levesque S, Dion N. Ultrasound-guided regional anesthesia for upper limb surgery. Can J Anaesth. 2013 Mar;60(3):304-20.

Similar block features were observed with infraclavicular and supraclavicular approaches, but infraclavicular block may be preferable to supraclavicular block due to the lower incidence of transient adverse events.
Source: Gurkan Y, Hosten T, Tekin M, Acar S, Solak M, Toker K. Comparison of ultrasound-guided supraclavicular and infraclavicular approaches for brachial plexus blockade. Agri. 2012 Oct;24(4):159-64.

Three cases of suprascapular nerve palsy after ultrasound-guided supraclavicular nerve block for routine outpatient upper extremity surgery are reported. All cases occurred in men who originally presented with shoulder pain, which resolved with time, followed by weakness in the supraspinatus and infraspinatus, which improved over time but did not resolve. One case resulted in ipsilateral phrenic nerve palsy as well.

Source: Draeger RW, Messer TM. Suprascapular nerve palsy following supraclavicular block for upper extremity surgery: report of 3 cases. J Hand Surg Am. 2012 Dec;37(12):2576-9.

Dexmedetomidine when added to local anaesthetic in supraclavicular brachial plexus block enhanced the duration of sensory and motor block and also the duration of analgesia. The time for rescue analgesia was prolonged in patients receiving dexmedetomidine. It also enhanced the quality of block as compared with clonidine.

Source: Swami SS, Keniya VM, Ladi SD, Rao R. Comparison of dexmedetomidine and clonidine (α2 agonist drugs) as an adjuvant to local anaesthesia in supraclavicular brachial plexus block: A randomised double-blind prospective study. Indian J Anaesth. 2012 May;56(3):243-9.

The supraclavicular approach of the brachial plexus has a high success rate including blockade of the ulnar and musculocutaneous nerve, which can be missed respectively with the interscalene and axillary approach. However, because of the proximity of the pleura, most anaesthesiologists have been reluctant to perform this supraclavicular approach. The introduction of ultrasound guidance techniques not only reduces the possible risk of pneumothorax but also allows a faster onset time of the block with a reduction of the local anaesthetic dose.

This makes the supraclavicular approach a valuable alternative to the axillary, interscalene and infraclavicular approach for upper limb surgery.
Source: Vermeylen K, Engelen S, Sermeus L, Soetens F, Van de Velde M. Supraclavicular brachial plexus blocks: review and current practice. Acta Anaesthesiol Belg. 2012;63(1):15-21.

Reliable detection of early low-volume intraneural injection using US is possible using expansion of the cross-sectional surface area of the nerve together with a change in echogenicity as markers.
Source: Moayeri N, Krediet AC, Welleweerd JC, Bleys RL, Groen GJ. Early ultrasonographic detection of low-volume intraneural injection. Br J Anaesth. 2012 Sep;109(3):432-8.

Ultrasound-guided supraclavicular brachial plexus block carries a risk for puncture of vascular structures. In this study, we determined the frequency with which the transverse cervical artery (TCA) and the dorsal scapular artery (DSA) are detected by ultrasound evaluation at 3 probe positions during supraclavicular block. Ultrasound examinations of the supraclavicular region were performed in 53 healthy adult volunteers. Ultrasound images of thesupraclavicular region were acquired at 3 probe positions: position A (the brachial plexus and the subclavian artery both lying on the first rib); position B (the brachial plexus on the first rib; the artery on the pleura); and position C (the brachial plexus between the anterior and middle scalene muscles). The primary outcome variables were the frequencies with which TCA and DSA were detected by 2-dimensional and color Doppler imaging at 3 specified probe positions.

TCA was more often detected than DSA in the vicinity of the brachial plexus in the supraclavicular region. Both TCA and DSA were least likely to be present in probe position A. Color Doppler, particularly for probe position A, may help to reduce the risk for inadvertent vascular puncture during ultrasound-guided supraclavicular block.

Source: Murata H, Sakai A, Hadzic A, Sumikawa K. The presence of transverse cervical and dorsal scapular arteries at three ultrasound probe positions commonly used in supraclavicular brachial plexus blockade. Anesth Analg. 2012 Aug;115(2):470-3.

A reduction of the volume of local anesthetics used for ultrasound-guided upper extremity blockades. Dexamethasone may prolong duration of brachial plexus blocks and more frequent use of perineural catheters is encouraged. Controversy over intra-epineurial injections exists and requires additional large-scale studies.
Source: Koscielniak-Nielsen ZJ, Dahl JB. Ultrasound-guided peripheral nerve blockade of the upper extremity. Curr Opin Anaesthesiol. 2012 Apr;25(2):253-9.

A case of the combination of a bilateral supraclavicular block and a caudal block in a two year old boy who needed amputations of four extremities after a pneumococcal sepsis. With the use of ultrasound guidance, reduction of local anaesthetic dose could be obtained in order not to reach the toxic dose of the local anaesthetic.
Source: Vermeylen K, Berghmans J, Van de Velde M, De Leeuw T, Himpe D. Ultrasound as guidance for a combined bilateral supraclavicular and caudal block, in order to reduce the total anaesthetic dose in a two year old child after a pneumococcal sepsis. Acta Anaesthesiol Belg. 2011;62(3):151-5.

Small branch vessels from the subclavian artery and vein were frequently evident, on ultrasound imaging, in close association with the nerve elements of the brachial plexus in the supraclavicular and interscalene regions. Appreciation of the presence of these vessels and their likely origin and course will aid the anesthesiologist in planning a safe nerve block.
Source: Muhly WT, Orebaugh SL. Sonoanatomy of the vasculature at the supraclavicular and interscalene regions relevant for brachial plexusblock. Acta Anaesthesiol Scand. 2011 Nov;55(10):1247-53.

Adult patients undergoing hand, wrist, or elbow surgery were enrolled in this prospective double-blind randomized study. Blocks were performed under ultrasound guidance. In group S (single injection), 30 mL of mepivacaine 1.5% was injected at the junction of the subclavian artery and the first rib. In group D (double injection), 15 mL of the same solution was injected at the site described above, then 15 mL was injected in the most superficial portion of the lateral aspect of the cluster formed by the brachial plexus trunks and divisions. The double-injection technique offers no benefit over a single injection for the performance of an ultrasound-guided supraclavicularblock.
Source: Roy M, Nadeau MJ, Cote D, Levesque S, Dion N, Nicole PC, Turgeon AF. Comparison of a single- or double-injection technique for ultrasound-guided supraclavicular block: a prospective, randomized, blinded controlled study. Reg Anesth Pain Med. 2012 Jan-Feb;37(1):55-9.

a case with partial analgesia after ultrasound-guided supraclavicular block for elbow surgery. The failure of the block was caused by the limited spread of local anesthetic because of blockage by a vessel (either transverse cervical artery or dorsal scapular artery) running through the brachial plexus. Anesthesiologists should be aware that cervical anatomy is complex and has anatomical variations. Thus, careful ultrasound screening of anatomical structure, especially using color Doppler, is important in performing brachial plexus block.
Source: Kinjo S, Frankel A. Failure of supraclavicular block under ultrasound guidance: clinical relevance of anatomical variation of cervical vessels. J Anesth. 2012 Feb;26(1):100-2.

The use of ultrasound-guided bilateral brachial plexus block in a patient with bilateral radius fractures. An axillary block was performed on the patient’s right and a supraclavicular block on her left using an in-plane (long-axis) needle insertion technique. Into each side was injected 20 ml 0.5% ropivacaine, giving a total volume (dose) of 40 ml (200 mg). Provisions were made for rescue analgesia or unplanned conversion to general anesthesia during the operation, but these were not needed; furthermore, no perioperative complications were observed. General anesthesia has traditionally been used for simultaneous surgery involving the bilateral upper extremities because of concerns relating to local anesthetic toxicity, phrenic nerve blockade, and pneumothorax. The ultrasound-guided technique facilitates a reduction in the minimal effective volume of local anesthetic and can prevent potentially critical complications. Moreover, the technique can be performed within the recommended safe dose limits of the anesthetic, rendering it an important option for bilateral upper extremity surgery.
Source: Toju K, Hakozaki T, Akatsu M, Isosu T, Murakawa M. Ultrasound-guided bilateral brachial plexus blockade with propofol-ketamine sedation. J Anesth. 2011 Dec;25(6):927-9.