Upper limb blocks

12 min read Last updated April 8, 2026

Surgical approach (context: common upper limb operations these blocks cover)

  • Shoulder surgery (arthroscopy, rotator cuff repair): patient often beach-chair or lateral; arthroscopic portals; irrigation fluid; may use arm traction
    • Key surgical issues: postoperative pain significant; diaphragmatic function important; risk of PONV/airway issues in beach-chair (hypotension/cerebral perfusion)
  • Clavicle fixation: supine; incision over clavicle; plate fixation; often day-case
    • Analgesia often requires combined cervical plexus + upper trunk/supraclavicular-type coverage depending on site
  • Upper arm/elbow surgery (ORIF, tendon repair): tourniquet frequently; variable incision; may need motor relaxation
    • Tourniquet pain may limit block-only technique for prolonged cases
  • Forearm/wrist/hand surgery (carpal tunnel, tendon repair, fractures): often tourniquet; short procedures; day-case
    • Distal blocks (median/ulnar/radial) can avoid proximal plexus complications and preserve diaphragmatic function

Anaesthetic management (typical)

  • Type of anaesthesia: regional alone (awake/light sedation) or regional + GA; GA alone if block contraindicated or patient preference
    • Shoulder: interscalene/upper trunk block often + light GA or sedation; consider diaphragm-sparing alternatives in respiratory disease
    • Forearm/hand: supraclavicular/infraclavicular/axillary or distal nerve blocks; often suitable for awake surgery
  • Airway: if GA—SGA common for distal limb surgery; ETT if long case, non-supine, aspiration risk, or need controlled ventilation (e.g., shoulder beach-chair with high risk of obstruction)
  • Duration: depends on surgery (hand 0.5–1.5 h; forearm/elbow 1–3 h; shoulder 1–3 h). Choose LA/adjuncts to match expected duration and discharge plan
  • Pain: shoulder and elbow typically very painful; hand/wrist moderate; tourniquet pain can be severe despite good surgical anaesthesia
    • Plan multimodal analgesia and rescue options (catheter, supplemental distal blocks, systemic analgesics)
  • Monitoring/positioning: standard monitoring; careful padding; consider arterial line for high-risk beach-chair; oxygen for sedated patients; capnography if deep sedation

Aims and indications

  • Provide surgical anaesthesia and/or postoperative analgesia for shoulder to hand surgery; reduce opioid use; facilitate day-case pathways; allow awake surgery in high-risk patients
  • Common indications: shoulder arthroscopy/repair (interscalene/upper trunk), clavicle surgery (cervical plexus + upper trunk), elbow/forearm surgery (supraclavicular/infraclavicular/axillary), hand surgery (axillary or distal nerve blocks)

Contraindications (absolute/relative)

  • Absolute: patient refusal; true LA allergy; infection at site; inability to cooperate when required; uncorrected severe coagulopathy (site-dependent)
  • Relative: anticoagulation/antiplatelets (follow RA-UK/ASRA principles; compressibility and consequence of bleeding matter); severe respiratory disease (avoid techniques with high phrenic nerve palsy risk); pre-existing neuropathy (document baseline; discuss risk); sepsis; raised ICP (rare relevance)
    • Interscalene: avoid/caution in severe COPD, contralateral diaphragmatic palsy, significant obesity/OSA if sedation planned

Anatomy essentials (brachial plexus + key nerves)

  • Roots C5–T1 → trunks (upper/middle/lower) → divisions → cords (lateral/posterior/medial) around axillary artery → terminal branches
  • Dermatomes/myotomes (high yield): C5 lateral upper arm; C6 thumb; C7 middle finger; C8 little finger/medial forearm; T1 medial upper arm
  • Terminal nerves: musculocutaneous (lateral forearm sensation; elbow flexion), median (palmar thumb–radial half ring; thenar), ulnar (little finger/ulnar half ring; intrinsic hand), radial (dorsal radial hand; wrist/finger extension), axillary (deltoid; regimental badge)
  • Important non-plexus contributors: intercostobrachial nerve (T2) supplies axilla/medial upper arm—tourniquet pain; supraclavicular nerves (C3–4) for clavicle/shoulder skin

Block selection by surgical site (practical mapping)

  • Shoulder/proximal humerus: interscalene or upper trunk block; consider suprascapular + axillary nerve blocks as diaphragm-sparing alternative for some shoulder procedures
  • Clavicle: superficial cervical plexus block ± interscalene/upper trunk (or selective supraclavicular nerve block depending on approach); GA often used
  • Elbow/forearm: supraclavicular (dense, rapid), infraclavicular (cords; good catheter option), axillary (more distal; avoids pneumothorax)
  • Wrist/hand: axillary or distal nerve blocks at forearm/wrist (median/ulnar/radial ± musculocutaneous); consider WALANT by surgeons (LA with adrenaline) where appropriate

Core technique principles (US-guided regional anaesthesia)

  • Pre-block: consent (including nerve injury, LAST, pneumothorax, phrenic palsy, Horner’s); document neuro exam; check anticoagulation; IV access; monitoring; resus drugs + intralipid immediately available
  • Asepsis: chlorhexidine in alcohol (allow to dry), sterile probe cover/gel, sterile gloves; avoid contamination of needle/probe
  • Needle/US: in-plane preferred for visualisation; optimise depth/gain; identify pleura/vascular structures; use colour Doppler if needed
  • Injection safety: frequent aspiration; incremental dosing; observe spread; stop for pain/paraesthesia or high resistance; consider opening injection pressure monitoring
  • Sedation: keep light enough to report symptoms of intraneural injection/LAST; maintain verbal contact; capnography if moderate/deep sedation

Key blocks: approaches, coverage, and complications (high yield)

  • Interscalene block (roots/trunks at C5–7 level): best for shoulder; often spares ulnar (C8–T1) → may need supplementation for distal arm surgery
    • Complications: phrenic nerve palsy (very common with classic volumes), Horner’s, hoarseness (recurrent laryngeal), intravascular injection (vertebral/ICA), epidural/intrathecal spread, nerve injury
  • Upper trunk block (C5–6): shoulder analgesia with reduced (not zero) risk of phrenic palsy vs interscalene; useful in respiratory compromise
  • Supraclavicular block (trunks/divisions “cluster of grapes” lateral to subclavian artery): dense block for arm below shoulder; rapid onset
    • Complications: pneumothorax (reduced with US but still possible), phrenic palsy (less than interscalene but occurs), vascular puncture, LAST
  • Infraclavicular block (cords around axillary artery deep to pectoralis minor): good for elbow/forearm/hand; catheter-friendly; lower pneumothorax risk than supraclavicular but still possible
    • Complications: vascular puncture, pneumothorax (rare), nerve injury; ensure identification of cords and pleura depth
  • Axillary block (terminal branches around axillary artery): good for forearm/hand; avoids pneumothorax/phrenic palsy; requires separate musculocutaneous block
    • Limitations: less reliable for tourniquet pain; may miss intercostobrachial (T2) and medial cutaneous nerves—consider additional infiltration
  • Distal nerve blocks (forearm/wrist): median, ulnar, radial (± musculocutaneous): preserve proximal motor function; minimal respiratory risk; ideal for minor hand surgery/analgesia supplementation
    • Beware: ulnar nerve at elbow (cubital tunnel) vulnerable; avoid intraneural injection; document pre-existing neuropathy (e.g., carpal tunnel)

Local anaesthetic choices (exam-relevant principles)

  • Choose LA based on desired onset/duration: lidocaine (fast, shorter), levobupivacaine/bupivacaine/ropivacaine (longer). Consider mixing only if you understand dose limits and toxicity risk
  • Dose safety: calculate maximum dose (mg/kg) and total mg; consider lower thresholds in frail/elderly, low muscle mass, pregnancy, cardiac disease; use lowest effective volume with US guidance
  • Adjuvants (local practice dependent): dexamethasone (perineural/IV) prolongs duration; clonidine/dexmedetomidine prolong but may cause hypotension/sedation; adrenaline reduces systemic absorption and is a marker for intravascular injection

Complications and their management

  • Local anaesthetic systemic toxicity (LAST): CNS symptoms (tinnitus, metallic taste, agitation, seizures) → cardiovascular collapse. Treat immediately
    • Management: stop injection; call for help; airway/100% O2; treat seizures (benzodiazepine); avoid large propofol doses in instability; start lipid emulsion; ALS with modified drug doses (avoid vasopressin; use small adrenaline boluses)
  • Nerve injury: multifactorial (needle trauma, intraneural injection, ischaemia, haematoma, surgical factors). Most resolve; persistent deficit needs urgent assessment
    • Prevention: avoid high-pressure injection; stop if pain/paraesthesia; keep patient communicative; use US to visualise needle tip; avoid multiple passes
  • Pneumothorax (supraclavicular/infraclavicular): dyspnoea, pleuritic pain, desaturation; may be delayed. Manage per severity (O2, imaging, decompression/chest drain)
  • Phrenic nerve palsy: dyspnoea, reduced FVC; usually transient; problematic in limited respiratory reserve. Use diaphragm-sparing techniques/low volumes; provide reassurance/O2; escalate if severe
  • Horner’s syndrome/hoarseness: expected with interscalene spread; reassure; exclude high neuraxial spread if severe symptoms
  • Vascular puncture/haematoma: direct pressure; consider anticoagulation status; monitor neurovascular compromise

Tourniquet pain (common viva topic)

  • Mechanism: C-fibre transmission and incomplete block of intercostobrachial (T2) and medial cutaneous nerves; central sensitisation with prolonged inflation
  • Prevention/management: ensure adequate proximal block; add intercostobrachial block or local infiltration; limit tourniquet time/pressure; systemic analgesia (opioid/ketamine), sedation, or convert to GA

Postoperative considerations

  • Discharge advice: protect insensate limb; sling if shoulder block; avoid heat sources; warn about rebound pain—start oral analgesia before block wears off
  • Follow-up: document block performed, LA type/volume, complications; provide contact pathway for persistent numbness/weakness or severe pain
You are asked to provide anaesthesia for shoulder arthroscopy in a patient with COPD. What regional options do you have and what are the risks?

Focus on analgesic efficacy vs respiratory compromise and phrenic nerve palsy.

  • Options: GA alone; GA + regional analgesia; regional with sedation (selected patients).
  • Interscalene: excellent shoulder analgesia but high incidence of ipsilateral phrenic nerve palsy → avoid/caution in significant COPD or contralateral diaphragm dysfunction.
  • Upper trunk block: similar analgesia for many shoulder procedures with reduced (not abolished) phrenic palsy risk; use low volume and US guidance.
  • Diaphragm-sparing alternatives: suprascapular + axillary nerve blocks (± local infiltration) for analgesia; may be less complete than interscalene for major repairs.
  • Plan: discuss with surgeon; consent re dyspnoea; consider minimal sedation, supplemental oxygen, and readiness to convert to GA.
Describe the anatomy relevant to a supraclavicular brachial plexus block and how you would identify it on ultrasound.

Examiners want: relationship to subclavian artery/first rib/pleura and the 'cluster of grapes' appearance.

  • Target: trunks/divisions of brachial plexus in the supraclavicular fossa.
  • Key relations: plexus typically lateral/superior to subclavian artery; first rib deep acts as backstop; pleura lies medial/deep—major hazard.
  • US appearance: hypoechoic round neural elements grouped together (“cluster of grapes”) adjacent to the artery; confirm pleura movement and rib shadow.
  • Technique points: in-plane needle; aim for spread around plexus; avoid medial/deep needle tip; aspirate and inject incrementally.
A patient develops tinnitus and perioral tingling during an axillary block. What is your diagnosis and immediate management?

This is early LAST until proven otherwise.

  • Diagnosis: local anaesthetic systemic toxicity (CNS prodrome).
  • Immediate actions: stop injection; call for help; maintain verbal contact; airway management and 100% oxygen; monitor ECG/BP; secure IV access if not already.
  • If seizure: benzodiazepine (e.g., midazolam); avoid large propofol doses if haemodynamically unstable.
  • Start lipid emulsion early if symptoms progress or any cardiovascular features; follow local LAST protocol; prepare for modified ALS.
  • After event: document, observe, consider admission; report via governance; counsel patient.
What nerves must be blocked for surgery on the hand, and how would you achieve this without a brachial plexus block?

Expect median/ulnar/radial (± musculocutaneous) and mapping to surgical site.

  • Core sensory supply: median, ulnar, radial nerves. Add musculocutaneous if lateral forearm incision/traction; consider intercostobrachial only if tourniquet/axillary incision.
  • Distal techniques: forearm blocks under US (identify nerve near accompanying artery/tendons) or landmark blocks at wrist; infiltrate surgical field as needed.
  • Advantages: avoids pneumothorax/phrenic palsy; preserves proximal motor function; useful in respiratory disease.
  • Limitations: may not cover tourniquet pain; may be insufficient for proximal procedures; requires multiple injections and careful sensory testing.
Compare interscalene, supraclavicular, infraclavicular and axillary approaches in terms of coverage and major complications.

Structure your answer: level of plexus, best indications, and signature complications.

  • Interscalene (roots/trunks): best shoulder/proximal humerus; may spare C8–T1; major issues—phrenic palsy, Horner’s, hoarseness, neuraxial/intravascular spread.
  • Supraclavicular (trunks/divisions): dense block for arm below shoulder; rapid onset; major issue—pneumothorax (plus phrenic palsy, vascular puncture, LAST).
  • Infraclavicular (cords): excellent for elbow/forearm/hand; catheter-friendly; lower pneumothorax risk than supraclavicular but not zero; vascular puncture possible.
  • Axillary (terminal branches): good for forearm/hand; avoids pneumothorax/phrenic palsy; must block musculocutaneous separately; tourniquet pain may persist.
How would you consent a patient for an interscalene block? Include specific risks.

Aim for material risks, common transient effects, and serious rare complications.

  • Explain purpose: anaesthesia/analgesia for shoulder surgery; expected duration; possibility of needing GA or supplemental analgesia.
  • Common/expected: numb/weak arm; temporary diaphragmatic weakness/shortness of breath; Horner’s syndrome; hoarse voice; bruising.
  • Serious but rare: LAST (seizure/cardiac arrest), nerve injury (persistent numbness/weakness), infection, bleeding/haematoma, pneumothorax (rare for interscalene but discuss if relevant), inadvertent neuraxial block.
  • Safety net: protect limb; when to seek help (progressive breathlessness, chest pain, persistent deficit).
A patient has severe pain under the tourniquet despite an apparently successful axillary block. Why, and what will you do?

Tourniquet pain is a classic scenario; discuss missing T2 and central mechanisms.

  • Why: tourniquet pain transmitted via intercostobrachial nerve (T2) and medial cutaneous nerves; C-fibres less blocked; prolonged inflation increases central sensitisation.
  • Immediate management: check block distribution; give systemic analgesia (opioid ± ketamine), titrated sedation; consider intercostobrachial block/local infiltration; ask surgeon to reduce pressure/time if possible.
  • If uncontrolled: convert to GA (SGA/ETT depending on aspiration risk and surgical factors).
What factors increase the risk of nerve injury with upper limb blocks, and how do you minimise this risk?

They want a multifactorial model and practical prevention steps.

  • Risk factors: intraneural/intrafascicular injection, high injection pressure, needle-nerve contact, multiple passes, anticoagulation/haematoma, pre-existing neuropathy/diabetes, prolonged tourniquet, surgical traction, patient unable to report pain (deep sedation/GA).
  • Minimise: US visualisation of needle tip; incremental injection with aspiration; stop if pain/paraesthesia/resistance; consider pressure monitoring; avoid heavy sedation; document baseline neuro status; choose compressible sites when anticoagulated.
  • Post-block: document findings; early recognition and referral if persistent motor deficit, severe neuropathic pain, or progressive symptoms.
Previous FRCA-style question: 'Outline the management of local anaesthetic systemic toxicity.'

Give a structured algorithm; include lipid therapy and ALS modifications.

  • Recognise: CNS prodrome → seizures → cardiovascular collapse; consider differential but treat as LAST if temporally related to LA injection.
  • Immediate: stop LA; call for help; airway/ventilation with 100% O2; avoid hypoxia/hypercapnia/acidosis (worsen toxicity).
  • Control seizures: benzodiazepines first line; consider small doses of propofol only if stable; consider neuromuscular blockade if needed to facilitate ventilation.
  • Lipid emulsion: start early in significant symptoms; continue per protocol; repeat bolus/infusion if instability persists (follow local guideline).
  • Cardiac arrest: modified ALS—small adrenaline doses, avoid vasopressin, avoid lidocaine/procainamide; consider amiodarone for refractory arrhythmias; continue resuscitation longer (lipid takes time).
  • Aftercare: ICU/HDU monitoring; investigate contributing factors (dose, site, intravascular injection); incident reporting; patient counselling.
Previous FRCA-style question: 'Discuss phrenic nerve palsy associated with brachial plexus blocks.'

Cover incidence by approach, clinical significance, and mitigation.

  • Mechanism: spread to phrenic nerve (C3–5) causing ipsilateral hemidiaphragm paresis; reduces FVC/FEV1.
  • Incidence: highest with interscalene; occurs with supraclavicular; lower with infraclavicular/axillary/distal blocks.
  • Clinical impact: usually tolerated in healthy patients; problematic in severe COPD, contralateral diaphragm dysfunction, significant obesity/OSA with sedation, or limited respiratory reserve.
  • Mitigation: choose diaphragm-sparing technique (upper trunk, suprascapular+axillary, infraclavicular/axillary/distal); reduce LA volume; use US guidance; avoid excessive medial spread.
  • Management: reassurance, oxygen, sit up; exclude pneumothorax if respiratory symptoms disproportionate; escalate if severe.

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