Bloqueo Infraclavicular Del Plexo Braquial

Techniques in Regional Anesthesia and Pain Management (2006) 10, 106-109

Infraclavicular brachial plexus block Daniel P. Monkowski, MD, Fabián Vitale, MD From the Division of Regional Anesthesia of the Superior Course AAARBA, UBA, Buenos Aires, Argentina. KEYWORDS: Regional anesthesia; Brachial plexus block; Infraclavicular approach; Peripheral nerve stimulation; Motor response; Local anesthetics

The infraclavicular block is a useful but underused technique for regional anesthesia of the upper limb. With a single shot dose of local anesthetic solution, it bathes all the cords of the brachial plexus. An advantage of the approach is the needle direction, because it moves away from the lung, avoiding respiratory complication (neumothorax). The block provides an effective, safe, and complete anesthesia of the upper limb and allows surgery of the hand, wrist, forearm, elbow, and third distal region of the arm. It is an ideal choice for patients in the ambulatory setting. The accurate way in which the catheter may be fixed on the anterior chest wall, makes it the best choice for continuous techniques. © 2006 Elsevier Inc. All rights reserved.

Infraclavicular block is an effective but underused technique for regional anesthesia of the upper limb. It is extremely useful because it allows an effective block of all the brachial plexus cords with a single dose of local anesthetic solution (LAS), producing an efficient blockade of all its terminal nerves.1 It was first described in 1917 by Bazy2 while looking into a safer technique than that of Kulenkampff’s3 supraclavicular approach (high neumothorax incidence) and more effective than Hirschel’s4 axillary approach to obtain anesthesia in the area of distribution of all the nerves of the brachial plexus. The technique consisted of introducing a needle just under the midclavicular point toward the Chassaignac’s tubercle (anterior tubercle of the transverse process of the sixth cervical vertebra). Then, other unsuccessful techniques (Labat, Balog, Babitzky, Kim) were described for decreasing the high incidence of neumothorax. For that reason, this technique was abandoned until 1973, when Raj described his new approach. With this technique, the needle was introduced 2.5 cm below the midclavicular point in a 60o angle related to the skin, toward the axillary pulse, using nerve stimulation for getting nerve structures and injecting 40 mL of local anesthetic solution with the arm of the patient abduced 90o (Figure 1). Raj’s approach was then modified by several authors (Sims, Salazar, Borgeat, Kilka) in search of higher efficacy and lower complications.5 In 1981, Whiffler described the coracoid ap-

proach. This technique was then modified by Wilson in 1998 using nerve stimulation.

Anatomy The limits of the infraclavicular region are: 1. 2. 3. 4.

Anterior: pectoralis major and minor muscles. Posterior: subscapularis muscle. Medial: the chest wall. Lateral: the humerus.

Before entering the infraclavicular region, the divisions of the brachial plexus combine again and pass below the clavicular midpoint to form the lateral, medial, and posterior cord of the plexus. They received their name due to their position around the axillary artery. At the lateral border of the minor pectoralis muscle, the cords divide in the terminal nerves of the brachial plexus: musculocutaneous, median, ulnar, radial, axillary, medial brachial cutaneous, and medial antebrachial cutaneous nerves.6 An important issue to highlight is the fact that the musculocutaneous, the axillary, and the medial brachial cutaneous nerves are not within the axillary sheath, since they leave the neurovascular bundle at the level of the coracoid process.

Indications Address reprint requests and correspondence: Daniel P. Monkowski, MD, Anesthesiologist CCPM, Director of Regional Anesthesia of the Superior Course AAARBA UBA, O’Higgins 3715 3 “A” Buenos Aires 1429, Argentina. E-mail address: [email protected]. 1084-208X/$ -see front matter © 2006 Elsevier Inc. All rights reserved. doi:10.1053/j.trap.2006.07.002

1. Surgery on the hand, wrist, forearm, elbow, and distal third of the arm. 2. Postoperative analgesia. 3. Continuous techniques.

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Techniques 1. Wilson (coracoid) (Figure 2)

Figure 1

Raj’s Technique.

Material ● ● ● ●

Nerve-stimulator Insulated needle: 21-G, 100 mm long Cutaneous electrode Skin marker and ruler (to identify anatomical landmarks)

Classification The infraclavicular approaches may be classified according to the entry site of the needle in:

Medial approaches (entry site: the midclavicular point)

Anatomical landmark: Coracoid process of the scapula. The patient is placed in the supine decubitus with the arm in neutral position and the hand on the abdomen. Once the coracoid process is identified and marked from its most prominent point, a line 2 cm medial and then 2 cm caudal is drawn. At this point, a 100-mm, 22-gauge insulated needle is introduced perpendicular to the table and slowly advances until a motor distal response (flexion or extension of the wrist or the fingers) with 0.5 mA intensity or less is obtained. Proximal motor responses (contraction of the triceps, biceps, flexor carpi radialis, and flexor carpi ulnaris) must not be considered because they are associated with high incidence of block failures. The reason would be that eliciting the median nerve indicates that the needle is at the center of the region where the nerves emerge. The somatotopic arrangement of fibers in the trunks of the brachial plexus shows that fibers in the central region of the bundle innervate the distal arm.7 The cords of the plexus are usually located at a depth of 5 cm (3-7 cm).8 If the right motor response is difficult to obtain, the needle must always be redirected to a lateral direction, never medial. A line drawn from the midclavicular point to the axillary pulse would help to determine the plexus course and thus redirect the needle in an accurate way. Advantages The anatomical landmark is easy to recognize. It is useful in patients who cannot move the upper extremity due to pain or trauma.9,10 Disadvantages It is not a good approach for catheter placement, because the perpendicular entry of the needle does not guarantee a good progression of it.

Raj technique Modified Raj techniques (Borgeat, Klaastad) Vertical technique (Kilka)

Lateral approaches (entry site: pericoracoid) Sims technique Coracoid techniques (Whiffler, Wilson) Lateral vertical technique (Salazar, Kapral, Grossi) Lateral sagittal technique (Klaastad) For performing surgeries on the upper limb with infraclavicular block as a sole regional anesthetic technique, we prefer lateral approaches, especially Wilson’s technique, because the main anatomical landmark (the coracoid process) is easy to recognize, even in obese patients, and the direction of the needle is perpendicular to the operating table. For continuous techniques and postoperative analgesia, we use medial approaches (Borgeat technique) because the direction of the needle in these approaches, tangential to the cords, permits an easy placement of a catheter.

Figure 2

Wilson Technique (Coracoid).

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Postoperative analgesia Bupivacaine 0.125% to 0.25% Ropivacaine 0.2% Load dose: 10 to 30 mL Continuous infusion: 4 to 8 mL/h Adjuvants Clonidine 1 ␮g/kg11 Epinephrine: 0.10 mg/20 mL LAS Onset time 20 to 30 minutes according to the LAS selected

Complications Figure 3

Borgeat’s Technique.

2. Borgeat (modified from Raj) (Figure 3) Anatomical landmarks Acromion Jugular notch Axillary artery With the patient in the supine position and the arm abduced 90°, a line from the ventral acromial process of the scapula to the jugular notch is drawn. The entry site is located 1 cm below the midpoint of the line, where a 100-mm, 21-gauge insulated needle is introduced at a 60o angle directed to the pulse artery. The plexus is usually reached at a depth of 6 cm.4-8 As in the Wilson lateral approach, the ideal motor responses are those elicited distally (hand movements). Advantages Accurate placement of a catheter for continuous block or postoperative analgesia. Disadvantages The position of the arm may be painful for patients with a traumatized limb. The needle itinerary through the pectoralis muscle may generate pain and discomfort.

1. Vascular puncture (hematoma formation) The medial approaches present higher rate incidence of vascular puncture than lateral approaches. The infraclavicular blockade of the brachial plexus must be considered as a deep block. Therefore, the same precautions as for central blockades in anticoagulated patients or in those with previous coagulopathy must be taken.12

2. Neuropathy The use of the nerve stimulator diminishes the possibility of neural damage by direct trauma caused by the needle.

3. Systemic toxicity a. Unnoticed intravascular injection b. Toxic dose

Contraindications ● ● ● ● ● ●

Previous coagulopathy Patient’s refusal Preexistent active neurological pathology Allergy to local anesthetics Infection located in the puncture place Systemic infection

Local anesthetic solution Short procedures Lidocaine 1.5% with epinephrine 1:200.000; volume: 40 to 50 mL Mepivacaine 1.5% to 2%

Long-lasting procedures Bupivacaine 0.375% with epinephrine 1:200.000; volume: 40 to 50 mL Ropivacaine 0.5%

Conclusions The infraclavicular block, as well as other supraclavicular approaches of the brachial plexus (Kulenkampff, subclavian perivascular, etc.) is an effective regional anesthetic technique for performing upper limb surgeries with a single shot dose of local anesthetic solution, because it bathes all the cords of the brachial plexus. An advantage of the approach is the needle direction, because it moves away from the lung, avoiding respiratory complications such as neumothorax in the Kulenkampff

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Infraclavicular Brachial Plexus Block

technique, as well as diaphragmatic paralysis in the interscalene block.13,14 The block provides an effective, safe, and complete anesthesia of the upper limb and allows surgery of the hand, wrist, forearm, elbow, and third distal region of the arm, although its level is lower than supraclaviculars. Infraclavicular block features make it an ideal choice for patients in the ambulatory setting.15 Lateral approaches (Wilson, Klaastad, Salazar) are preferable for anesthesia, whereas medial approaches are the best choice for catheter placement and continuous techniques. The accurate way in which the catheter may be fixed on the anterior chest wall, avoiding dislocations and infections in comparison to other approaches (axillary, interscalene, etc.) makes it the best choice for prolonged analgesia.16

References 1. Grossi P, Collucia R, Tassi A, et al: The infraclavicular brachial plexus block. Tech Reg Anesth Pain Manage 3:217-221, 1999 2. Bazy L, Pauchet V, Sourdat PL: Anesthesie Regionale. Paris, G Doin et Cie, 1917, pp 222-225 3. Kulenkampff D: Anesthesia of the brachial plexus. Zentralbl Chir 38:1337-1350, 1911 4. Hirschel G: Anesthesia of the brachial plexus for operations on the upper extremity. München Med Wochenschr 58:1555-1556, 1911 5. Raj P: Infraclavicular approaches to brachial plexus anesthesia. Tech Reg Anesth Pain Manage 1:169-177, 1997

109 6. Neal J, Hebl J, Gerancher J, et al: Brachial plexus anesthesia: essentials of our current understanding. Reg Anesth Pain Med 27:402-428, 2002 7. Borgeat A, Ekatodramis G, Dumont C, et al: An evaluation of the infraclavicular block via a modified approach of the Raj technique. Anesth Analg 93:436-441, 2001 8. Klaastad O, Lilleas FG, Rotnes JS, et al: Magnetic resonance imaging demonstrates lack of precision in needle placement by the infraclavicular brachial plexus block described by Raj et al. Anesth Analg 88:593-598, 1999 9. Wilson J, Brown D, Wong GY, et al: Infraclavicular brachial plexus block: parasagittal anatomy important to the coracoid technique. Anesth Analg 87:870-873, 1998 10. Kapral S, Jandrasits O, Schabernig R, et al: Lateral infraclavicular plexus block vs. axillary block for hand and forearm surgery. Acta Anesthesiol Scand 43:1047-1052, 1999 11. Murphy D, Chan V, McCartney C, et al: Novel analgesic adjuncts for brachial plexus block: a systematic review. Anesth Analg 90:1122-1128, 2000 12. Monkowski DP: Anestesia del Miembro Superior Otras Alternativas. XXXII Congreso Argentino de Anestesiología Mendoza, 2003 13. Rodriguez J, Barcena M, Rodriguez V, et al: Infraclavicular brachial plexus block effects on respiratory function and extent of the block. Reg Anesth Pain Med 23:564-568, 1998 14. Salazar C, Espinosa W: Infraclavicular brachial plexus block: variation in approach and results in 360 cases. Reg Anesth Pain Med 24:411416, 1999 15. Hadzic A, Vloka J, Arliss J, et al: A comparison of infraclavicular nerve block versus general anesthesia for hand and wrist day-case surgeries. Anesthesiology 101:127-132, 2004 16. Ilfeld B, Morey T, Enneking FK, et al: Continuous infraclavicular brachial plexus block for postoperative pain control at home. Anesthesiology 96:1297-1304, 2002