Upper extremity blocks
Sandra L. Kopp, MD, Susan M. Moeschler, MD and Denise J. Wedel, MD
Successful neural blockade of the upper extremity requires extensive anatomic knowledge of the brachial plexus, from its origin as the roots emerge from the intervertebral foramina and of the nerves of the arm and forearm (Figure 127-1). Also important is knowledge of the side effects and complications of peripheral nerve blocks in the upper extremity, as well as the clinical application of available local anesthetic agents for these blocks. Finally, one must not underestimate the role of appropriate sedation during placement of the nerve block and during the surgical procedure (Table 127-1).
Table 127-1
Regional Anesthetic Techniques for Upper Extremity Operations
| Brachial Plexus Technique | Level of Blockade | Peripheral Nerves Blocked | Surgical Applications | Comments |
| Axillary | Peripheral nerves | Radial, ulnar, median; musculocutaneous unreliably blocked | Operations of the forearm and hand | Unsuitable for proximal humerus or shoulder surgeryRequires patient to abduct the arm |
| Supraclavicular | Distal trunk–proximal cord | Radial, ulnar, median, musculocutaneous, axillary | Operations of the midhumerus, elbow, forearm, and hand | Risk of pneumothorax requires caution in ambulatory patientsPhrenic nerve paresis in 30% of cases |
| Interscalene | Upper and middle trunks | Entire brachial plexus, although inferior trunk (ulnar nerve) is inconsistently blocked | Surgery to shoulder, proximal and mid humerus | Phrenic nerve paresis in 100% of patients for duration of the blockUnsuitable for patients unable to tolerate a 25% reduction in pulmonary function |
Adapted from Kopp SL, Horlocker TT. Regional anaesthesia in day-stay and short-stay surgery. Anaesthesia. 2010;65(Suppl 1):84-96.
Interscalene block
Technique
With the patient in the supine position, the patient’s head is turned away from the side to be anesthetized. The lateral border of the sternocleidomastoid muscle is palpated and marked; identification of the muscle is facilitated by having the patient briefly lift his or her head. The interscalene groove may be palpated by rolling the fingers posterolaterally from the muscle border, over the belly of the anterior scalene muscle. A line is extended laterally from the cricoid cartilage to intersect the vertical line of the interscalene groove; this represents the level of the C6 transverse process. The external jugular vein often crosses at this level but is not a reliable anatomic landmark (Figure 127-2).
