Regional

Question 1

Interscalene block

Answer 1

C5/6/7 nerve roots - traffic light sign

TYPICAL DOSE
- 7 - 15ml
- Higher dose (>10ml) more likely to get phrenic nerve involvement although difficult to avoid in general)

CONTRAINDICATIONS
- Respiratory insufficiency or contralateral phrenic nerve palsy
- Existing RLN or VC palsy

COMPLICATIONS
- Acute and chronic events ~0.4%

- NERVE INJURY
	○ Common for C6 / C7 to split proximally. Prudent to avoid injecting between these two nerves as may get an intraneural injection
	○ DORSAL SCAPULAR and LONG THORACIC nerve also traverse the MSM
	
- PHRENIC NERVE
	○ Located ANTERIOR to ANTERIOR SCALENE muscle
	○ Blockade occurs in almost 100% cases, with loss of 25% respiratory function
		
- RECURRENT LARYNGEAL NERVE BLOCK
	○ Single side = Paramedian VC position with hoarse voice

- HORNERS SYNDROME
	○ OCULOSYMPATHETIC PAREISIS
	○ Stellate ganglion
	○ Miosis / partial ptosis / anhydrosis / enopthalmos

- HAEMATOMA / VASCULAR INJURY
- LOCAL ANAESTHETIC TOXICITY
- UNINTNENDED SPINAL / EPIDURAL ANAESTHESIA
- PNEUMOTHORAX --> Rare

Question 2

Supraclavicular block

Answer 2

INDICATION
- Arm, elbow, forearm, hand.
- Shoulder surgery also POSSIBLE

Primary neural coverage
* Roots covered: C5–T1 (most complete upper-limb block)
* “Spinal of the arm” — dense, fast-onset block

Dermatomal coverage
* C5–T1 reliably
* Often includes T2 (intercostobrachial nerve) via local spread (variable)

Clinical analgesic coverage
* Excellent for:
○ Elbow, forearm, wrist, and hand surgery
○ Distal humerus
* Variable coverage:
○ Shoulder (inferior to interscalene block)

What it may not cover well
* Shoulder joint (suprascapular nerve often incompletely blocked)
* Proximal medial upper arm (if T2 spared)

Motor effects (expected)
* Dense motor blockade of:
○ Shoulder (variable)
○ Elbow
○ Wrist
○ Hand

Onset and reliability
* Rapid onset
* High success rate
* Uniform spread due to compact plexus anatomy

Common associated effects (important)
* Phrenic nerve block: possible but less frequent than interscalene
* Pneumothorax: rare with ultrasound guidance
* Horner’s syndrome: uncommon
* Recurrent laryngeal nerve block: rare

NYSORA exam pearls
- Best single-injection block for upper limb surgery below the shoulder
- Provides the most complete sensory and motor block of the arm
- Preferable to interscalene in patients with limited respiratory reserve

NYSORA LA choice
* Ropivacaine 0.5% (or 0.2–0.375% for analgesia)
* Bupivacaine 0.25–0.5%
* Lidocaine (± adrenaline) for fast onset
NYSORA volumes
- Typical ultrasound-guided volume: 15–25 mL
- Many achieve reliable block with ~20 mL