Upper limb blocks

12 min read Last updated April 9, 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

Test yourself…

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 &#039,cluster of grapes&#039, 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: &#039,Outline the management of local anaesthetic systemic toxicity.&#039,

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: &#039,Discuss phrenic nerve palsy associated with brachial plexus blocks.&#039,

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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