Level of difficulty: Intermediate to Advanced
Anatomy: Roots of the brachial plexus (C5–C7) between anterior and middle scalene muscles
Surface anatomy: Posterior triangle of the neck, lateral to cricoid cartilage at C6 level
Indications: Shoulder surgery, proximal humerus fracture
Nerves blocked: C5–C7 roots (suprascapular, axillary, lateral pectoral, musculocutaneous)
Positioning: Supine with head turned contralaterally
Scanning technique: Transverse orientation over neck at C6 level
Structures to identify: Anterior and middle scalene muscles, brachial plexus roots, carotid artery
Block performance: In-plane lateral-to-medial approach
Position/Ergonomics: Standing at head or side of patient
Probe: High-frequency linear probe
Settings: Nerve preset with adequate contrast
Depth: 2–4 cm
Needle size: 50 mm echogenic needle
Needling technique: In-plane lateral-to-medial
Optimal needle tip position: Between C5 and C6 roots
Drug choice: 0.5% ropivacaine or levobupivacaine
Volume: 10–15 ml
Optimal current if NS used: 0.3–0.5 mA
Muscle responses acceptable: Deltoid, biceps twitch
Testing block success: Shoulder abduction/sensory loss over deltoid
Pearls: Avoid intraneural injection; watch for phrenic nerve palsy
Side effects: Diaphragmatic paresis, Horner’s syndrome, hoarseness
Complications: Intravascular injection, pneumothorax
Continuous techniques:
- Indication: Prolonged shoulder analgesia
- Kit: Standard catheter-over-needle
- Catheter: Inserted 3–4 cm beyond needle tip
- Regime: 5–8 ml/hr 0.2% ropivacaine
Contraindications: Severe pulmonary disease, coagulopathy
References: Neal JM et al. Reg Anesth Pain Med. 2010