Adequate management of pain after shoulder surgery is paramount to post-operative recovery. Regional anesthesia has proven to provide superior pain control and recovery. Several brachial plexus blocks have been described with intrascalene being the most common employed. A full knowledge of anatomy as well as the indications and potential complications associated with regional anesthesia is required by the physician.
22 Perioperative Pain Management for Shoulder Surgery
I. General overview
First peripheral block was performed by William Halsted with cocaine in 1885
Over the past 30 years there has been an increasing trend in the use of peripheral nerve blocks for postoperative pain management
Adequate pain control via peripheral block:
Decreases hospital length of stay
Allows transition from traditional inpatient surgery to outpatient
Decrease opioid use and associated opioid side effects
Enhances participation in rehabilitation
Improve functions and patient satisfaction outcomes
Vital to understand the indications and potential complications associated with regional anesthesia.
Brachial plexus (▶ Fig. 22.1 ):
Five roots: C5, C6, C7, C8, and T1
Level of intrascalene block.
Three trunks: Upper, middle, and lower
Level of supraclavicular block.
Six divisions: Anterior and posterior divisions of three trunks
Three cords: Posterior, lateral, and medial
Level of intraclavicular block.
Five branches: Median, axillary, radial, musculocutaneous, and ulnar nerves
Shoulder sensory innervation:
Superficial cervical plexus (C3–C4):
i. Supraclavicular nerve.
T2 nerve root.
Shoulder capsule, subacromial bursa, acromioclavicular joint, cutaneous tissue:
Suprascapular nerve—primarily C5, C6 with some C4.
Four anatomic regions pertinent to peripheral nerve blocks (▶ Fig. 22.2 ):
Potential space between anterior and middle scalenes
Targets brachial plexus at root-trunk level
Most commonly preformed
Effective for shoulder, proximal humerus, and distal clavicle
Superior to clavicle at the level of plexus trunks
Between anterior and middle scalenes at the first rib
Apical lung vulnerable
Suitable for shoulder; theoretically does not cover superior aspect of shoulder, arm, and elbow: forearm hand adequately covered.
Boarders consist of:
i. Superior—posterior aspect of clavicle
ii. Inferior—soft tissues of axilla
iii. Anterior—pectoralis minor
iv. Posterior subscapularis.
Level of the cords before axillary and musculocutaneous nerves exit
Shoulder not covered; arm, elbow, and forearm hand adequately covered.
Axillary and suprascapular:
In combination similar shoulder coverage compared with intrascalene block
i. Located beneath glenohumeral joint between the chest wall and medial upper arm
ii. In isolation may be adequate for elbow surgery.
i. Level of the suprascapular notch.