Educational+Material+RA+Handbook+Final

THE ABBOTT POCKET GUIDE

TO PRACTICAL PERIPHERAL NERVE BLOCKADE

Sponsored by Abbott Laboratories Ltd, Abbott House,

Norden Road, Maidenhead, Berkshire, SL6 4XE

DR BARRY NICHOLLS Consultant Anaesthetist Taunton and Somerset Hospital

DR DAVID CONN Code No: HXCHI2003104

Date of preparation: Oct 2003

Consultant Anaesthetist Royal Devon and Exeter Hospital

DR ALICE ROBERTS Senior Teaching Fellow Department of Anatomy University of Bristol

CONTENTS / 00

Contents SECTION 1 - Introduction Golden rules of regional anaesthesia Local anaesthetics Physicochemical properties of local anaesthetics Local anaesthetic additives Complications of peripheral regional anaesthesia Treatment of toxicity Electrical stimulation of peripheral nerves

01 02 03 04 05 05 06

SECTION 2 - Ophthalmic local anaesthesia Topical corneoconjunctival anaesthesia Peribulbar anaesthesia Sub-Tenon’s anaesthesia

09 09 12

SECTION 3 - Upper limb blocks Elicited motor responses Brachial plexus - anatomy Cutaneous innervation chart Cervical plexus block • Superficial • Deep Interscalene block • Winnie • Meier Subclavian perivascular block Vertical infraclavicular block Subcoracoid infraclavicular block Suprascapular nerve block Axillary block Midhumeral block Elbow blocks Wrist blocks Digital nerve block Webspace block IVRA (Bier’s block)

22 24 26 28 30 32 34 36 40 46 50 52 54

SECTION 4 - Trunk blocks Thoracic paravertebral block Intercostal nerve block Penile block Ilioinguinal/iliohypogastric block (hernia block) Caudal epidural - children

56 58 59 60 62

15 16 17 18 20

00 / CONTENTS

SECTION ONE / INTRODUCTION / 01

Contents SECTION 5 - Lower limb blocks Elicited motor responses Lumbosacral plexus - anatomy Cutaneous innervation chart Lumbar plexus block Sacral plexus block (parasacral approach) Sciatic nerve block • Labat (posterior approach) • Beck (anterior approach) • Lateral approach • Raj (inferior approach) Femoral nerve block Lateral cutaneous nerve of thigh block Knee / popliteal blocks • Lateral • Prone • Supine Intra-articular knee block Saphenous nerve block Ankle and foot blocks • Ankle • Midtarsal • Digital SECTION 6 - Practical application of peripheral nerve blocks Shoulder Elbow Wrist Hand Hip Knee Ankle Foot Catheter techniques Infusion/bolus guidelines

Golden Rules of Regional Anaesthesia 65 66 67 68 70

1. Always discuss the procedure with the patient, explaining benefits and risks and obtaining consent. 2. Always discuss with the surgeon the procedure you intend to perform. 3. Always discuss potential complications and side effects, document these in the notes/anaesthetic chart.

72 74 76 78 80 82

4. Always perform the procedure in the patient’s best interest NOT the anaesthetist’s.

84 86 87 88 89

7. Always fractionate doses greater than 5mls.

90 96 96

99 99 99 100 101 101 101 102 104 106

5. Always perform the technique in an appropriate setting with resuscitation equipment and drugs available. 6. Always have intravenous access and monitor to RCA standards.

8. Always document procedure carried out, recording complications and/or problems e.g. pneumothorax, paraesthesia, bleeding.

KNOW THE ANATOMY & TECHNIQUE WELL. BE PREPARED TO FAIL – HAVE A PLAN.

IMPORTANT: All blocks in this book are “tried and tested” by the clinical authors and are presented in good faith. This book is not intended as a stand-alone training in regional anaesthesia. We encourage all clinicians to get hands-on training. No responsibility can be accepted for complications arising from the use of the techniques described. In addition to the potential side effects of each “block” each anaesthetic agent has potential side effects. For details see summary of product characteristics of individual agent.

02 / SECTION ONE / INTRODUCTION

SECTION ONE / INTRODUCTION/ 03

Local anaesthetics

200 Long 94% High 400 Slow

150 Long 95% High 1000 Slow 8.1

150 Long 95% High 1000

400 Medium

Medium 65%

55% Low

POTENCY

Medium 150

50 Fast

Slow 8.1

8.1

*British National Formulary

Lipid solubility Concentration of local anaesthetic Motor nerves have more myelin than sensory Ropivacaine low lipid sol, high pKa - sensory > motor

S-

• • • •

Ropivacaine

Differential block

S-

Protein binding at site of action Mass of drug and absorption from site Drug’s inherent vasodilatation effect Vasodilator Lidocaine > Prilocaine – increased absorption therefore shorter action Ropivacaine no vasodilatation - relative vasoconstrictor

Levobupivacaine

• • • • •

R&S

Duration of action

Bupivacaine

• Directly proportional to lipid solubility

7.7

Potency

R&S

Unionised base is lipid soluble - crosses into nerve. pKa is the pH at which [base] = [charged cation] The closer the pKa is to pH 7.4 the greater amount base, faster onset !concentration of the drug (! conc. gradient), faster onset

Prilocaine

• • • •

Fast

Onset

RELATIVE LIPID SOL

Properties relating to local anaesthetics

ONSET

Reversible blockade of sodium channels in excitable/conducting neural tissue Administered as water-soluble hydrochlorides (B.HCL) After injection - base released by relative alkalinity of tissues (pH-pKa) B.HCL+HCO3↔B+H2CO3+CL Unionised base diffuses into nerve axoplasm, partially ionised again B+H+↔BH+ Ionised base BH+ enters sodium channel-from interior of nerve - preventing depolarisation

Physicochemical properties of local anaesthetics

• • • • • • •

PROTEIN BINDING

Mode of action

7.7

DURATION OF ACTION

Lidocaine/Prilocaine/Bupivacaine/Levobupivacaine/Ropivacaine Stable in solution Usually weak acid pH 4-5.5 Slowly broken down by amidases in liver Hypersensitivity reactions low

pKa

• • • • •

Achiral

Amides (-NHCO-)

Lidocaine

BNF * MAX DOSE (mg)

Procaine/Cocaine/Chloroprocaine/Amethocaine Relatively unstable Rapidly hydrolysed by plasma cholinesterase Para-amino benzoate associated with hypersensitivity & allergic reactions

STEREO-ISOMER

• • • •

300 500 with epinephrine

Esters (COO-)

04 / SECTION ONE/ INTRODUCTION

SECTION ONE / INTRODUCTION / 05

Local anaesthetic additives

Complications of peripheral regional anaesthesia

Bicarbonate

Definitions

• Added to increase pH of solution – increase unionised LA • May increase speed of onset • Risk of precipitation if > 1ml 8.4% NaHCO3 per 10mls LA

A side effect is a reversible, non-serious, unwanted effect of a block i.e. phrenic nerve palsy and diaphragmatic paralysis (temporary) after an interscalene block. A complication is a potentially serious, or irreversible unwanted effect i.e a pneumothorax after a subclavian perivascular block, or an intravenous injection of LA, or permanent nerve damage after any block.

Epinephrine (Adrenaline) • • • • • • •

Decrease vascular reabsorption – increasing duration – more drug available Reduction of peak plasma levels (Lidocaine) Reduced benefit in long acting LA e.g. bupivacaine and Chirocaine Less effective in epidurals May have spinal effects via spinal alpha receptors Effective conc. 5mcg/ml = (1:200,000) Epinephrine (Adrenaline) max dose 200mcg Avoid in terminal extremity /digital blocks / sciatic nerve blocks

Technique related • • • • •

Direct neural trauma Bleeding and haematoma Intravascular injection Pneumothorax Inadvertent epidural/intrathecal injection – widespread block

Clonidine

Drug related

• • • • • • • •

• • • • • •

Acts on spinal alpha 2 adrenergic receptors Prolongs duration of sensory and motor block “Strengthens” local anaesthetic effect Induces post block analgesia Reduce wide dynamic neurone (WDN) activity - inhibiting nociceptive transmission Effective in epidural/caudal/spinal analgesia Epidural/intrathecal use limited by hypotension and sedation Dosage 1mcg/kg in peripheral blocks

Opiates • • • •

Spinal/peripheral opiate receptors Proven synergism with local anaesthetic in epidurals/spinals All opioids have been used, debatable benefit in peripheral blocks Intra-articular morphine 2-5mg in knee surgery

Ketamine • • • •

NMDA receptor/weak local anaesthetic properties Paediatric caudal epidurals PRESERVATIVE FREE DRUG ESSENTIAL Dose 0.5mg/kg in paediatric caudals

Hyaluronidase • Only appears effective in peribulbar and retrobulbar blocks of the eye • Aids in the onset of block by increased diffusion of LA through tissues

Toxicity Immediate- intravascular injection Delayed- absorption from vascular site/relative overdose Overdose Anaphylactoid reaction Methaemoglobinaemia (prilocaine)

Treatment of toxicity General • STOP INJECTION • Airway, Breathing, Circulation

CNS Toxicity • • • • •

Administer oxygen Sedation – midazolam, propofol If breathing inadequate or absent start manual ventilation & intubate if necessary Administer fluid replacement Vasopressor drugs as necessary

CVS Toxicity • • • • • • •

Supplementary oxygen Intravenous fluid Bradycardia – glycopyrrolate, atropine Hypotension – ephedrine, metaraminol or epinephrine (adrenaline) Intubation and ventilation 100% oxygen Cardiopulmonary resuscitation (CPR) Bretylium for ventricular arrhythmias

Methaemoglobinaemia • Methylene blue 1mg/ kg

06 / SECTION ONE / INTRODUCTION

Electrical stimulation of peripheral nerves Rheobase is the minimum current in milliamps required to create a nerve impulse. Chronaxie is the minimum duration of stimulus, at twice the rheobase, that must be applied to the nerve to initiate an impulse. Chronaxie varies depending on the type of nerve; A alpha myelinated fibres (motor) 50-100msec, A delta myelinated fibres (sensory) 150msec, C unmyelinated fibres (sensory) 400msec.

Using a peripheral nerve stimulator (PNS) • Connect the stimulating needle to the cathode and ground electrode or ECG pad to anode. Negative to Needle (Black) Positive to Patient (Red). • Flush the needle with local anaesthetic, puncture skin and then disconnect the syringe to allow free flow of blood in case of inadvertent vascular puncture. • Insert the insulated needle of your choice using a standard approach. Start with current of 1mA, a frequency of 2Hz and a pulse width of 100msec. Maximize motor response without paraesthesia and reduce current towards 0.5 mA. • Reduce current to threshold (minimum current to obtain motor response) – if 0.2mA or less consider intraneural placement - reposition. • Inject 1 ml of LA, motor response should disappear (nerve is displaced by solution – increasing needle-nerve distance). If motor response still presents suspect misplacement of needle - start again. • Increase current to again obtain desired motor response (Coulomb’s law - inverse square law) confirming needle is still in correct location. • Inject full volume after careful aspiration, fractionating dose if greater than 5mls and aspirating regularly to check for intravascular placement. Any pain or increased resistance to injection, stop immediately and reposition needle.

SECTION TWO Ophthalmic Local Anaesthesia

SECTION TWO / OPHTHALMIC ANAESTHESIA / 09

Ophthalmic local anaesthesia Topical corneoconjunctival anaesthesia Levobupivacaine 0.75%, Amethocaine 1% (may sting/cloud cornea) Oxybuprocaine 0.4% (Benoxinate) Proxymetacaine 0.5% (least stingy and least toxic to the cornea)

Peribulbar anaesthesia Indications: Operations on the globe including cataract and retinal surgery Landmarks: Sclerocorneal junction (limbus), medial canthus, caruncle and inferior orbital rim Technique: • Instill topical local anaesthetic drops • Perform inferolateral injection +/- medial injection

Inferolateral injection: Palpate the groove on the inferior orbital rim at the junction of the maxilla and zygoma, in line with the limbus. At a point 1mm above the rim of the orbit just lateral to this point - either transcutaneously (through lower lid) or transconjunctival Needle: 25G 25mm (bevel facing globe) Direction: Backwards, slightly inferiorly to contact bone. Redirect posteriorly under globe Depth: 20-25mm (hub level with iris) Volume: 4-6 mls (see Figures 1 & 2 ) LA: Lidocaine 2% with Hyaluronidase 10-30units/ml 1:1 mixture of Levobupivacaine 0.75% + Lidocaine 2% with Hyaluronidase 10-30units/ml

Medial injection: At a point medial to the caruncle Needle: 25G 25mm (bevel facing globe) Direction: Directly backward, angled slightly medial to touch medial wall of orbit, then withdrawn and redirect posteriorly, parallel to the medial wall. Depth: 20-25mm Volume: 3-5mls (see Figures 3 & 4) Side effects: Conjunctival oedema/haemorrhage Proptosis Complications: Retrobulbar haemorrhage Subarachnoid injection Perforation of globe Extra-ocular muscle damage from intramuscular injection Clinical tips: Always know axial length (AL). Risk of globe perforation increases as AL increases. Extreme caution if AL >27mm, consider only a medial canthus injection or a sub-Tenon’s block

10 / SECTION TWO / OPHTHALMIC ANAESTHESIA


FIGURE 1: Inferolateral injection

FIGURE 3: Medial injection

FIGURE 2: Inferolateral injection

FIGURE 4: Medial injection

12 / SECTION TWO / OPHTHALMIC ANAESTHESIA


Sub-Tenon’s block Indications: Operations on the globe including cataract and retinal surgery Landmarks: Sclerocorneal junction (limbus) Technique: (See Figures 5 & 6) • Instill topical local anaesthetic drops • Retract the eyelids with a speculum • In the inferonasal quadrant, the conjunctiva is raised with Moorfield’s forceps • At a point 5mm from the limbus a small incision in the conjunctiva is made using Westcott spring scissors. Dissection of this space inferonasally between the sclera (vascular) and Tenon’s capsule (white, avascular) Needle: Insert a blunt, curved sub-Tenon cannula backwards beyond the equator. Volume: 3-5 mls LA: Lidocaine 2% with Hyaluronidase 10-30units/ml 1:1 mixture of Levobupivacaine 0.75% + Lidocaine 2% with Hyaluronidase 10-30units/ml Complications: Bleeding Side effects: Chemosis (corneal oedema)/swelling Subconjunctival haemorrhage Proptosis Comparison with peribulbar: Lower risk of bleeding but poorer akinesia

FIGURE 5: Sub-Tenon dissection

FIGURE 6: Sub-Tenon injection

MIDHUMERAL & MULTI INJECTION AXILLARY

INFRACLAVICULAR

SUBCLAVIAN PERIVASCULAR

INTERSCALENE

Technique

✔ ✘ ✔✔ ✔✔ ✔✔

Medial cord Subscapular Musculocutaneous Median Ulnar Radial

Extensors elbow, wrist and fingers

✔✔

✔✔

✔✔ ✔✔ ✔

✔ ✘ ✘ ✔✔ ✔✘

Too deep, outside of plexus

Caution too medial

Poor response. Too lateral/superficial

Too superficial

Acceptable for shoulder surgery Too anterior Too posterior

Accept Comment

Extensors of forearm and hand Flexors of the forearm and small muscles of the hand Subscapularis Biceps, Brachialis, Coracobrachialis (BBC) Flexor digitorum superficialis and FCR Adductor pollicis/FDP Flexor carpi ulnaris

Middle trunk Lower trunk

C5 root Phrenic Dorsal scapular C5-6 root Upper trunk

Nerve

Lateral cord Posterior cord

Deltoid Diaphragm Levator scapulae/rhomboids Biceps Deltoid, Biceps, Brachialis, Coracobrachialis (BBC) & Triceps Primarily extensors flexors forearm/hand Flexors of forearm and fingers BBC flexors of the forearm and hand

Shoulder abduction/arm abduction Hiccup Elevation of scapula Elbow flexion Arm abduction elbow flexion Wrist and finger extension Finger and wrist flexion Flexion elbow, wrist and hand supination Wrist and fingers extension Wrist and fingers flexion, thumb adduction Scapula posterior adduction Elbow flexion Wrist flexion+ pronation. Finger flexion Thumb adduction, ring and little finger flexion Wrist and finger extension especially thumb

Muscle Innervated

Motor Response

Elicited motor responses for upper limb blocks

SECTION THREE SECTION THREE / UPPER LIMB BLOCKS / 15

Upper limb blocks

16 / SECTION THREE / UPPER LIMB BLOCKS

SECTION THREE / UPPER LIMB BLOCKS / 17

Brachial plexus anatomy 1 C5 2

1

3

C6

r pe Up

C7

4

3

le dd Mi

5

C8

6 7

r we Lo La ter al

8 9

2

4

11

5

r rio ste Po

T1 12

Me dia l

6

17 7 16 15 14 13

12

8 9

8

10

10

11 10

FIGURE 7: Brachial plexus anatomy

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17)

Dorsal scapular nerve Nerve to subclavius Suprascapular nerve Lateral pectoral nerve Upper and lower subscapular nerves Axillary nerve Lateral root of median nerve Musculocutaneous nerve Radial nerve Ulnar nerve Median nerve Medial root of median nerve Medial cutaneous nerve of forearm Thoracodorsal nerve Medial cutaneous nerve of arm Medial pectoral nerve Long thoracic nerve

C5 C5,6 C5,6 C5,7 C5,6 C5,6 C6,7 C5,7 C5-T1 C7-T1 C6-T1 C8-T1 C8-T1 C6-8 C8,T1 C8,T1 C5-7

Branches of the cords Lateral cord 4,7,8 Medial cord 10,12,13,15,16 Posterior cord 5,6,9,14

FIGURE 8: Cutaneous innervation of arms

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12)

Supraclavicular nerves Superior lateral cutaneous nerve of arm (axillary nerve) Intercostobrachial nerve Inferior lateral cutaneous nerve of arm Medial cutaneous nerve of arm (medial cord) Lateral cutaneous nerve of forearm (musculocutaneous nerve) Medial cutaneous nerve of arm (medial cord) Radial nerve Median nerve Ulnar nerve Posterior cutaneous nerve of arm (radial nerve) Posterior cutaneous nerve of forearm (radial nerve)



Superficial cervical plexus block Indication: Analgesia for neck line insertion Cutaneous analgesia for shoulder surgery In combination with deep cervical plexus blocks for awake carotid artery surgery Bilateral for thyroid surgery analgesia Landmarks: Mid-point of the posterior border of sternocleidomastoid muscle (SCM) Technique: (See Figures 9 & 10) • Insert needle along posterior border of SCM both caudad and cephalad. Needle must puncture first fascial layer Needle: 21 - 23 g needle Direction: Cranial and caudal Stimulation/endpoint: Puncture fascial layer. Local anaesthetic should form a “sausage” along the posterior border of SCM. Volume: 10ml LA: 1% Prilocaine, 1% Lignocaine 0.25% Levobupivacaine Side effects: None Complications: Haematoma (rare)

FIGURE 9: Superficial cervical plexus block

(1) Transverse cervical nerves (2) Supraclavicular nerves (3) Greater auricular nerve

(4) Lesser occipital nerves (5) Sternocleidomastoid muscle

1 2 5 3

4

FIGURE 10: Superficial cervical plexus anatomy



Deep cervical plexus block Indications: Anaesthesia and analgesia for carotid surgery, cysts, lymph node biopsy, other superficial surgery to the neck Landmarks: Thyroid cartilage (C4) Posterior border of Sternocleidomastoid muscle (SCM) Interscalene groove Technique: (See Figures 11 & 12) • Identify the posterior border of SCM at Thyroid cartilage level C4 • Place a finger beneath the lateral border of SCM onto belly of scalenus anterior • Move finger laterally feeling for interscalene grove Needle: 25mm - 50mm insulated/non-insulated Direction: Towards contra-lateral elbow. Medially, caudally and dorsally. Depth: 10mm - 20mm. Insert until paraesthesia are felt or bone of C4 transverse process is contacted. After careful aspiration inject LA. Volume: 8mls - 10mls LA: 1% Lidocaine, 1% Prilocaine 0.25% - 0.5% Levobupivacaine Side effects: Phenic nerve block Recurrent laryngeal nerve block Stellate ganglion block Complications: As with interscalene block Clinical tips: The single injection technique is as effective as the multiple injection technique.

FIGURE 11: Deep cervical plexus block

(1) Sternocleidomastoid muscle (2) Phrenic nerve (3) Ansa Cervicalis

(4) Brachial plexus (5) Deep cervical plexus

1

2 3 4 5 1

FIGURE 12: Deep cervical plexus with sternocleidomastoid muscle cut and retracted



Interscalene block Winnie’s approach Indications: Shoulder & humerus surgery Landmarks: Cricoid cartilage (C6) Posterior border of Sternocleidomastoid muscle (SCM) Interscalene groove Technique: • Identify posterior border of sternocleidomastoid muscle (SCM) at cricoid level (C6) • Place finger beneath lateral border SCM onto belly of scalenus anterior • Move fingers laterally feeling for groove – separating scalenus anterior from scalenus medius (See Figures 13 & 14)

Needle: Direction: Depth: Stimulation:

Volume: LA:

25mm-50mm insulated Towards contra lateral elbow 10-20mm (very near the surface) Deltoid (shoulder surgery) Elbow flexion (humeral surgery) If the phrenic nerve is stimulated - needle too anterior If the dorsal scapular nerve is stimulated - needle too posterior 10-20mls upper roots/analgesia 20-40mls lower roots/anaesthesia 1% Lidocaine , 1% Prilocaine 0.25%-0.5% Levobupivacaine

Side effects: Phrenic nerve block - 100% Recurrent laryngeal nerve block - 15% Stellate ganglion block - 20% Complications: Epidural/spinal injection Vertebral artery puncture Bilateral spread Spinal cord injury Pneumothorax Clinical tips: Never do block on anaesthetised patients Caution with patients with respiratory problems The plexus is rarely (if ever) more than 20mm deep to the skin Paraesthesia to the operative area is an acceptable alternative to electrical nerve stimulation

FIGURE 13: Winnie’s interscalene block

(1) (2) (3) (4) (5)

Clavicle Phrenic nerve Subclavian artery Brachial plexus Dorsal scapular nerve

(6) (7) (8) (9)

First rib Stellate ganglion Scalenus anterior Scalenus medius

1

2 3

7 8

4

5

9 6

FIGURE 14: Interscalene anatomy



Interscalene block Meier’s approach Indications: Shoulder and humeral surgery Difficult anatomy - poor identification of interscalene groove, short neck Continuous catheter techniques Landmarks: The posterior border sternocleidomastoid muscle (SCM) Thyroid cartilage prominence (C4) Subclavian artery - above the clavicle Technique: • Mark the posterior border of sternocleidomastoid muscle at the level of the thyroid prominence • Palpate the subclavian artery as it passes over the 1st rib behind the clavicle • A line joining these two marks approximates to the interscalene groove

1

4

2

(See Figures 15 & 16)

Needle: Direction:

50mm insulated Caudally, passing along the long axis of the interscalene groove towards the subclavian artery Depth: 35-50mm Stimulation: Deltoid (shoulder surgery) Elbow flexion (humerus) Volume: 10-20mls upper roots/analgesia 20-40mls lower roots/anaesthesia LA: 1% Lidocaine , 1% Prilocaine 0.25%-0.5% Levobupivacaine Side effects: As with Winnie’s technique Complications: Inadvertent intravascular injection Pneumothorax - very low incidence Clinical Tips: Reduced risk of epidural/intrathecal injection Easier catheter placement because of angle of approach

FIGURE 15: Meier’s interscalene block

(1) Thyroid cartilage (2) Subclavian artery (3) Brachial plexus

(4) Posterior border of sternocleidomastoid

1 2 3

4

FIGURE 16: Interscalene anatomy



Subclavian perivascular block (SPV) Indication: Elbow, wrist and hand surgery Landmarks: Interscalene groove, subclavian artery Technique: • Identify the interscalene groove • Move finger inferiorly down the groove until pulsation of subclavian artery is felt (only found in 50% of patients) or skin begins to flatten out over supraclavicular fossa • With your finger in the groove, insert a needle in the posterior part of the groove posterior to the artery (See Figures 17 & 18)


50mm insulated Parallel to the floor, directly caudad (aiming at ipsilateral great toe). 1.5-4cm Flexion/extension wrist and fingers If no paraesthesiae or twitch found then redirect fractionally anterior/posteriorly in groove If accidental arterial puncture - move needle posteriorly If you contact 1st rib then “walk” antero-posteriorly along rib CAUTION: Absolutely no medial intent or medial angulation of the needle Volume: 0.5ml/kg up to 40mls LA: 1% Prilocaine, Lidocaine 0.25% - 0.5% Levobupivacaine Side effects: Horner’s syndrome/recurrent laryngeal nerve block Complications: Vascular puncture Inadvertent intravascular injection Pneumothorax - less than 1:1000 in experienced hands. Clinical Tips: Fast onset block, because of the narrowing of the perivascular sheath at this level. Ulnar border missed in approximately 5% of blocks.

FIGURE 17: Subclavian perivascular approach - Finger in the groove and/or subclavian artery

(1) Clavicle (2) Subclavian artery (3) Brachial plexus

(4) First rib (5) Scalenus anterior (6) Scalenus medius

1

2 5 3

6

4

FIGURE 18: Subclavian perivascular anatomy



Vertical infraclavicular block (VIB) Indications: Surgery of the elbow, forearm and hand. Landmarks: Anterior process of the acromion, jugular notch, subclavian artery. Technique: • Lie the patient flat, with one pillow behind the head • Mark the mid-point between the anterior process of the acromion and the jugular notch, below the clavicle • Note the position of the subclavian artery above the clavicle. The plexus will lie lateral to this point, after passing below the clavicle

2


50mm insulated. 2-5 cm Absolutely vertical direction of needle. No medial angulation. Wrist / finger extension - accept, posterior cord. Pectoral muscle twitch - don't accept, needle too medial or superficial. Elbow flexion - don't accept, lateral cord, needle too lateral or superficial. No twitch - needle too lateral Caution: No medial angulation of needle, only move needle in horizontal plane medial / lateral Volume: 0.5ml/kg to 50ml LA: 1% Prilocaine, 1% Lignocaine 0.25% - 0.5% Levobupivacaine Side effects: Rarely recurrent laryngeal nerve block, stellate ganglion block Complications: Vascular puncture Inadvertent intravascular injection Pneumothorax - less than 1:1000 in experienced hands. Clinical Tips: Keep the needle as close to the inferior surface of the clavicle as possible. Move the needle medially or laterally but keep the needle absolutely vertical. Care with very thin patients as plexus may be less than 2cm deep (lung may be less than 5cm deep)

1

Needle: Depth: Direction: Stimulation:

FIGURE 19: Vertical infraclavicular block

(1) Anterior process of acromion (2) Jugular notch

(3) Subclavian artery

1 2 3

FIGURE 20: Infraclavicular anatomy



Subcoracoid infraclavicular block Indications: Elbow, wrist and hand surgery Landmarks: Coracoid process Technique: • Identify the coracoid process (shrug shoulder) • Mark the most anterior prominence • Mark a point 2cm inferior and 1-2 cm medial (See Figures 21 & 22 )


50-80mm insulated Perpendicular in all planes 3-8cm Wrist / finger extension - accept, posterior cord. Pectoral muscle twitch - don't accept, needle too medial or superficial. Elbow flexion - don't accept, lateral cord, needle too cephalad or superficial. Wrist flexion, thumb adduction - only accept if surgery is in ulnar distribution, medial cord. Posterior scapular movements - don't accept, too deep, outside plexus CAUTION - no medial angulation of needle/only move needle in sagittal plane (cephalad / caudad) Volume: 0.5 mls/kg to 50mls LA: 1% Prilocaine/Lidocaine Levobupivacaine 0.25%-0.5% Side effects: Nil of note Complications: Vascular puncture Inadvertent intravascular injection Clinical tips: 2cm & 1cm distances will need to be reduced proportionally in smaller patients

1cm 2cm

2

FIGURE 21: Subcoracoid infraclavicular block

(1) Clavicle (2) Tip of coracoid process (3) Pectoralis minor

(4) Subclavian artery (5) Cords of brachial plexus

1

2

4 3

2cm

5

1cm

FIGURE 22: Subcoracoid infraclavicular block


SECTION THREE / UPPER LIMB BLOCKS /33

Suprascapular nerve block Indication: Analgesia for shoulder operations Landmarks: Inferior angle of scapula, spine of scapula Technique: • With the patient sitting, or lying (operative side up) • Mark the mid-point of the scapular spine • Draw a line from the inferior angle of the scapula to this point • Move 1cm superiorly • Insert the needle 90º in all planes Needle: 50mm insulated or uninsulated Direction: Perpendicular to skin downwards onto bone (suprascapular fossa) Stimulation/endpoint: Move needle anteriorly until either, paraesthesiae (into shoulder), abduction/elevation arm (supra/infraspinatus) or needle passes into the suprascapular notch. Volume: 10-15mls LA: 0.5% Levobupivacaine Side effects: Nil of note Complications: Very rarely pneumothorax due to incorrect landmarks.

2

1

FIGURE 23: Suprascapular block

(1) Inferior angle of scapula (2) Spine of scapula (3) Suprascapular nerve

3 2

1

FIGURE 24: Suprascapular nerve anatomy



Axillary block Indications: Elbow, forearm and hand surgery Landmarks: Axillary artery Insertion of pectoralis major muscle Technique: • Identify the axillary artery with the arm abducted to 90º and the elbow flexed • Draw a line down from the anterior axillary fold (insertion of pectoralis major) crossing the artery • Fix the artery between index and middle finger and insert a needle to pass above or below the artery (See Figure 25 ) • Above the artery - (median, musculo-cutaneous) • Below the artery - (ulnar) • Below / Behind the artery - (radial) (See Figure 26 ) Needle: 25-50mm insulated/uninsulated Direction: 45º to the skin, proximally Depth: 10-15mm Stimulation: Median – index/middle finger - flexion Ulnar – thumb adduction, little finger flexion Radial – thumb extension Musculocutaneous – elbow flexion Volume: Single injection: 0.5ml/kg up to 50mls Multiple-injection: Identify each individual nerve. 7-10mls each nerve. Intercostobrachial nerve – subcutaneous infiltration across floor of the axilla – decreases upper arm tourniquet pain. Alternative techniques Transarterial - deliberate transfixion of axillary artery Loss of resistance - click/pop on entering fascial sheath Subcutaneous infiltration - fanwise infiltration above/below artery Deliberately elicit paraesthesia in the nerve supplying target area Continuous axillary catheter- identify primary nerve supplying target, insert catheter either above (median) or below (ulnar/radial) artery LA: 1% Lidocaine, 1% Prilocaine 0.25% - 0.5% Levobupivacaine Side effects: Nil of note Complications: Inadvertent vascular injection Nerve damage Clinical Tips: Single shot almost always misses the musculo-cutaneous branch, also misses the radial in about 25%.

FIGURE 25: Axillary block

(1) (2) (3) (4) (5)

Musculocutaneous nerve Median nerve Medial cutaneous nerve of forearm Axillary artery Ulnar nerve

(6) Radial nerve (7) Medial cutaneous nerve of arm (8) Coracobrachialis/biceps muscle (9) Triceps muscle (10)Humerus

1 2 8

3 4

5 6 10

7 9

FIGURE 26: Cross section at neck of humerus



Midhumeral block Indications: Elbow, forearm and hand surgery Landmarks: Insertion of deltoid muscle Brachial artery Technique: • Mark the brachial artery in the bicipital groove • Draw a line crossing the artery at the level of the insertion of deltoid • This should be approximately three or four finger breadth’s below the axilla

2

3

8 7

9

c/s


Needle: Direction:

50mm insulated Median - above (lateral) and parallel to the artery(See Figure 29) Musculocutaneous - 45º above the artery and lateral to humerus (See Figure 32)

Ulnar - below (medial to) the artery/superficial to triceps (See Figure 30)

Radial- below (medial to) the artery and humerus. Pass needle to posterior border of humerus (nerve in spiral groove)(See Figure 31 ) Volume: 6-10mls on each nerve Stimulation: Median - index/middle finger - flexion Musculocutaneous - elbow flexion Ulnar - little finger flexion/thumb adduction Radial - thumb extension LA: 1-2% Lidocaine, 1% Prilocaine 0.5% Levobupivacaine Side effects: Nil of note Complications: Bleeding/bruising 5% Clinical Tips: Use long acting LA on nerve supplying area of operation and short acting LA on the rest. Additional subcutaneous infiltration 5 mls - medial cutaneous nerve of arm/forearm and intercostobrachial nerve to aid tourniquet comfort.

1

5

4

6

FIGURE 27: Midhumeral anatomy

(1) (2) (3) (4) (5)

Ulnar nerve Median nerve Musculocutaneous nerve Medial cutaneous nerve of arm Medial cutaneous nerve of forearm

(6) (7) (8) (9)

Brachial artery Biceps / coracobrachialis muscle Pectoralis major Triceps muscle

8

8 1 2 3 10

4

9

11 11 11

FIGURE 28: Midhumeral anatomy at level of deltoid insertion

(1) (2) (3) (4) (5) (6)

Medial cutaneous nerve of arm Musculocutaneous nerve Median nerve Brachial artery Ulnar nerve Medial cutaneous nerve of forearm

(7) Radial nerve (8) Biceps muscle (9) Deltoid muscle (10)Coracobrachialis muscle (11) Triceps muscle

5 6 7



FIGURE 29: Midhumeral block. Approach to median nerve

FIGURE 31: Midhumeral block. Approach to radial nerve

FIGURE 30: Midhumeral block. Approach to ulnar nerve

FIGURE 32: Midhumeral block. Approach to musculocutaneous nerve



Elbow blocks Indications: Minor forearm surgery & hand surgery ‘Top-up’ to augment or expedite brachial plexus blocks Landmarks: Elbow crease, brachial artery, tendon of biceps muscle LA: 1-2% Lidocaine , 1% Prilocaine 0.25%-0.5% Levobupivacaine

Lateral cutaneous nerve of forearm • Subcutaneous infiltration along lateral border of biceps tendon 5-8 mls

Posterior cutaneous nerve of forearm • Subcutaneous infiltration between the lateral epicondyle and the olecranon 5-8mls

Ulnar nerve (See Figures 33,34 & 37) Techniques:

Median nerve (See Figures 33,34 & 35) • Flex the elbow, mark the elbow crease • Identify the brachial artery on this line and mark a point just medial to the artery Needle: Direction: Depth: Stimulation: Volume:

25-50mm insulated/uninsulated 45º to the skin/proximally 10-15mm, below bicipital aponeurosis (pop or click felt) Flexion of fingers accept. Pronation of wrist alone inadequate Paraesthesia into thumb index or middle finger accept 5mls slowly

Medial cutaneous nerve of the forearm • Subcutaneous infiltration along the medial border of biceps tendon 5-8mls

Radial nerve (See Figures 33,34 & 36) • Palpate the groove between lateral border of biceps tendon & brachioradialis • Mark a point 1.5-2cm proximal to the elbow crease in this groove Needle: 50mm insulated Direction: Towards the lateral epicondyle / slightly cephalad Depth: 2-4cms Stimulation: Extension of the thumb accept. Wrist extension alone inadequate. Volume: 5mls

• Palpate the ulnar sulcus (medial epicondyle). At a point 2cm proximal to the sulcus Needle: 50mm insulated Direction: 45º to the skin along a line joining the ulnar sulcus and axilla Depth: 1-3cms Stimulation: Flexion ring finger, adduction of thumb Volume: 5mls Side effects: Nil Complications: Nil of note Clinical Tips: Inject the LA slowly into tight tissues Avoid injection of ulnar nerve in ulnar sulcus Only accept distal finger movement and not forearm Inconsistent anatomy - causing varying nerve distribution with overlapping cutaneous innervation The major nerves at the elbow only have cutaneous innervation to the hand. Cutaneous innervation of the forearm comes from higher branches Paraesthesia is not routinely sought but if encountered then withdraw the needle by 1-2mm and slowly inject LA


Medial


Lateral

Medial

Lateral

1 5

2 2

3

5 6 4 7

3

1 C/S

4

8

FIGURE 34: Cross section of arm at supracondylar level

(1) (2) (3) (4) FIGURE 33: Cubital fossa

Ulnar nerve Median nerve Brachial artery Radial nerve

(5) (6) (7) (8)

Biceps muscle Brachialis muscle Brachioradialis muscle Triceps muscle



2

1

FIGURE 35: Median nerve block

FIGURE 37: Ulnar nerve block

(1) Brachial artery (2) Biceps tendon

2

1

FIGURE 36: Radial nerve block



Wrist block Indications: Hand surgery Landmarks: Palmaris longus (PL), flexor carpi radialis (FCR), ulnar artery, flexor carpi ulnaris (FCU), radial styloid

3

(See Figures 38-41 ) 3

Technique: 1

Median nerve

2

• Make a fist. Identify the tendons of FCR & PL • Mark a point 3-5cms proximal to the distal palmar crease between these tendons (if no PL present -1cm medial to FCR) (See Figure 42) Needle: 25G 25mm non-insulated Direction: 45º to the skin, towards the wrist Depth: 10-15mm Stimulation: Paraesthesia into thumb or index finger Volume: 3-5mls

1

Palmar cutaneous branch (medial nerve) • Infiltrate superficially proximally to the flexor retinaculum 3-5mls

FIGURE 38: Cutaneous innervation

Ulnar nerve • Make a fist. Identify the tendon of flexor carpi ulnaris (FCU) • At a point 2cm proximal to the distal palmar crease beneath the medial border of the tendon (See Figure 43) Needle: 25G 25mm uninsulated Direction: Medially beneath tendon of FCU, towards radial border of wrist Depth: 10-15mm Stimulation: Paraesthesiae into little finger Volume: 3-5mls

(1) Median nerve (2) Ulnar nerve (3) Radial nerve

Dorsal cutaneous branch (ulnar) • Subcutaneous infiltration over the ulnar aspect of the wrist at this level - 3mls

2

3

Superficial radial nerve • Palpate the styloid processes of the radius • Infiltrate subcutaneously from this point over the posterior aspect of the wrist to the mid-point of the dorsum of the wrist 5-8mls (See Figure 39)

FIGURE 39: Superficial radial nerve


1

3

2

6

7


5

4

FIGURE 40: Wrist anatomy

(1) (2) (3) (4)

Radial artery Flexor carpi radialis Median nerve Palmaris longis

7

6

(5) Ulnar artery (6) Ulnar nerve (7) Flexor carpi ulnaris

5

4

FIGURE 41: Cross section at level of distal radius

3

2

FIGURE 42: Median nerve block

1

FIGURE 43: Ulnar nerve block



Digital nerve block Indication: Surgery distal to the base of the proximal phalanx Landmarks: Base of proximal phalanx Technique: • Dorsal injection • On the dorsolateral aspect of finger. At the base of the proximal phalanx Needle: Direction: Volume: LA:

25G 25mm uninsulated Vertically to slide past base of phalanx. Medial and lateral injections of each phalanx needed for complete anaesthesia 2-3ml (injecting to palmar surface and on withdrawal) 1% Lidocaine, Prilocaine 0.25% Levobupivacaine

Side effects: Nil of note Complications: Possible vascular compromise from pressure Accidental vascular puncture / haematoma Clinical tips: Massage to aid spread NEVER use vasoconstrictors around end arteries

FIGURE 44: Digital nerve block

FIGURE 45: Cross section at distal metacarpals



Webspace block Indications: As for digital nerve block Landmarks: Metacarpophalangeal joints Technique: • Insert the needle in the webspace till the tip of the needle is proximal to the MCP joint Needle: 23/25G 50mm uninsulated Depth: Just proximal to MCP joint Volume: 3-5mls in each space Clinical tips: Massage to aid spread NEVER use vasoconstrictors around end arteries

FIGURE 46 & 47: Webspace block


Intravenous regional anaesthesia (IVRA) (Bier’s block) Indication: Minor superficial surgery forearm & hand Reduction minor fractures +/- K wiring Technique: • Apply double/single cuff to upper arm • Cannulate a suitable vein distal to the cuff • Insert a cannula (safety needle) in a different limb • Elevate or use an Esmark (or similar) bandage to exsanguinate the arm • Inflate lower cuff followed by upper cuff to 100mmHg above systolic BP- deflate lower cuff inject local anaesthetic (can switch cuffs after 10mins) Volume: Small arm 40mls Medium arm 50mls Large arm 60mls LA: 0.5% Prilocaine (up to 300mgs) keep cuff inflated for 15mins minimum 0.5% Lidocaine (max adult dose 250mg) keep cuff inflated for 20mins minimum. Clinical tips: Contra-indicated in children Never use Bupivacaine / Levobupivacine / Ropivacaine Unsatisfactory in fat arms & hypertensive patients (systolic BP greater than 200mmHg) Only use in short operations <30mins

FIGURE 48: Bier’s block

SECTION FOUR Trunk blocks

56 / SECTION FOUR / TRUNK BLOCK

SECTION FOUR / TRUNK BLOCK / 57

Thoracic paravertebral block Indication: Analgesia for rib fractures, thoracic surgery, breast surgery, open cholecystectomy and renal surgery Landmark: Spinous process and transverse process (TP) of corresponding vertebra (See Figures 49 & 50)

Technique: • Patient sitting or lying with operative side up • Palpate the spinous process and mark a point 2.5cms lateral to its most cephalad aspect Direction: Perpendicular to skin Needle: 22G 80mm spinal needle/ insulated needle Depth: Initially contact transverse process (2-5cm), reangle needle to pass above the TP advancing 1-1.5cm Stimulation/Endpoint: Loss of resistance or paraesthesiae (motor response - intercostal muscle twitch) Volume: 5mls per level or high volume 15mls* LA: 0.25% - 0.5% levobupivacaine Side effects: Epidural spread Contralateral spread Complications: Intravascular injection, intrathecal injection, pneumothorax Clinical tips: *Catheter/high volume techniques - work well in thoracic region (15mls -blocks 3-5 segments) Thoracic surgery T5/6 Fractured ribs variable level Cholecystectomy/Renal multiple levels T8-T12 Catheter T10 Avoid lateral angulation of needle - increased risk of pneumothorax

FIGURE 49: Thoracic paravertebral block

(1) Vertebral body (2) Transverse process (3) Rib

(4) Nerve root in paravertebral space (5) Pleura

Lung 1 5

4 2 3

FIGURE 50: Cross section through thoracic vertebra



Intercostal nerve block

Penile block

Indication: Analgesia for fractured ribs, open cholecystectomy Landmark: Angle of the rib Technique: • With the patient lying affected side up, or sitting • Palpate the angle of the rib, (found immediately lateral to the border of erector spinae muscle) • Holding the rib between two fingers, insert the needle to contact the inferior border • Redirect the needle to pass just below the rib (See Figure 51) Needle: 22G uninsulated short bevelled/ 22g 50cm insulated needle connected to extension tubing Direction: Perpendicular to skin Depth: 2-5mm deep to the inferior border of rib End point: Contact lower border rib, walk off rib, advance till loss of resistance Volume: 5mls at each level LA: 0.5% Levobupivacaine Complications: Pneumothorax Absorption toxicity Inadvertent intravascular injection

Indication: Circumcision Technique: • Palpate symphysis pubis (SP), above the root of penis • Mark two points (0.5cm infant, 1.0cm child/adult) either side of the midline below the SP (See Figures 52 & 53) Needle: 22-25G short bevelled Direction: Posteriorly, medial and slightly caudally- until loss of resistance elastic recoil with penetration of Buck’s fascia Depth: 8-30mm (correlates with age) Volume: 0.1ml/kg (max 5mls) per side (child) LA: 0.5% Levobupivacaine Infiltrate subcutaneously around root of penis onto the lateral side of scrotum, blocking branches from ilioinguinal and genitofemoral nerves (1-5mls depending on size of child - 0.25% Levobupivacaine) Never use epinephrine (adrenaline) containing solutions Complications: Intravascular injection Puncture corpus cavernosum/dorsal vessels (haematoma)

(1) (2) (3) (4)

Rib Intercostal vein Intercostal artery Intercostal nerve

1

2 3 4

FIGURE 52: Penile block

FIGURE 51: Intercostal nerves and vessels

2 3 4

1

(1) Symphysis pubis (2) Membranous fascia (Scarpa’s)

FIGURE 53: Cross-section through pubic bone

(3) Penile fascia (Buck’s) (4) Subpubic space



Ilioinguinal / iliohypogastric nerve blocks (Hernia block) Indications: Inguinal surgery, including orchidopexy Landmarks: Anterior superior iliac spine (ASIS), deep inguinal ring (1-1.5cm above mid inguinal point) Technique: • Mark a point 2cm medial to ASIS in adults and 1cm in children Needle: 22G 50mm short bevelled Direction: Perpendicular to skin Depth: 10-40 mm

Iliohypogastric nerve • Following initial click (pop) as needle penetrates external oblique aponeurosis inject 8mls of LA to block the iliohypogastric nerve

Ilioinguinal nerve • Either insert the needle deeper till a second click, as internal oblique is penetrated and inject 8 mls to block the ilioinguinal nerve • OR direct the needle posterolaterally to touch inner aspect of ileum and inject 8 ml of LA whist withdrawing blocking the ilioinguinal nerve

Intercostal nerves • Fan wise subcutaneous infiltration above the aponeurosis will block cutaneous supply from lower intercostal nerves and sub-costal nerve (T12) • Fan wise subcutaneous infiltration from pubic tubercle superiorly & laterally will block contra lateral innervation

Genitofemoral nerve • Palpate the deep ring, insert needle into inguinal canal to block the genitofemoral nerve - 5mls (can only reliable be performed at operation) Volume: 30mls LA: 0.25-0.5% Levobupivacaine Complications: Intravascular injection Intraperitoneal injection Femoral nerve block Clinical tips: In children limit volume 2.5mg/kg Levobupivacaine (0.25%-0.5%) Always warn the patient about the risk of femoral nerve block and subsequent inability to weight bear.

FIGURE 54: Hernia block

(1) (2) (3) (4)

(5) (6) (7) (8)

Rectus abdominis muscle External oblique muscle Iliohypogastric nerve Internal oblique muscle

Ilioinguinal nerve Lateral femoral cutaneous nerve Femoral nerve Ilium

1

2 3 4 5

6 7

8

FIGURE 55: Cross section at the level of the anterior superior iliac spine



Caudal epidural - children Indications: Circumcision, orchidopexy, herniotomy and analgesia and/or anaesthesia for lower limb surgery Landmarks: Posterior superior iliac spines (PSIS), sacral cornua, sacral hiatus Technique: • Either prone or on the side. Palpate PSIS’s, the sacral hiatus is at the apex of an equilateral triangle whose base is formed by a line joining the PSIS’s • OR palpate the sacral cornua, the depression between and immediately inferior to them is the sacral hiatus (See Figures 56 & 57) Needle: 22G intravenous cannula Direction: Cephalad at 45º in the sagittal plane (15º in babies - sacrum flatter) Depth: 5-10mm (insert needle 3mm into canal) - advancing cannula 10 mm off needle End point: ‘Pop’ felt – sacro-coccygeal membrane pierced Volume:

LA:

Segmental level of operation Lumbo-sacral Thoraco-lumbar Mid-thoracic

Dose (ml/kgs) 0.5 1.0 1.25

FIGURE 56: Caudal injection

0.25% Levobupivacaine (volumes >20mls change to 0.125% ) 0.2% Ropivacaine

FIGURE 57: Caudal injection

Quadriceps femoris Gastrocnemius and all muscles in posterior compartment of lower leg

Patellar twitch Foot plantar-flexion/ inversion

Peroneal muscles

Sartorius

Quadriceps femoris

Patellar twitch Anterior thigh

Psoas major

Hip flexion

Common peroneal (fibular) nerve

Tibial nerve

Femoral nerve

Nerve to sartorius

Direct muscle stimulation Femoral nerve L3/4 components

✔✔

✔✔

✔✔

✘

✘ ✔✔

Too superficial

Too deep

Too medial/too caudad

✘ L4 root to the sacral plexus

Knee flexion

Hamstrings

Accept Comment

Motor Response Muscle Innervated Nerve

(ALL APPROACHES) Foot dorsi-flexion and eversion

SCIATIC NERVE BLOCK

FEMORAL NERVE BLOCK (ANT APPROACH)

LUMBAR PLEXUS (POSTERIOR)

Technique

Elicited motor responses for lower limb block

SECTION FIVE SECTION FIVE / LOWER LIMB BLOCKS / 65

Lower limb blocks

66 / SECTION FIVE / LOWER LIMB BLOCKS

SECTION FIVE / LOWER LIMB BLOCKS / 67

L1 1

L2

2 3

L3 1

L4

2

4

5

11

3 L5 4

5 S1

6

6

7

S2

8

12

S3

7

9

13

10

14

S4

8

FIGURE 59: Cutaneous innervation of the lower limbs

FIGURE 58: Lumbosacral plexus

(1) (2) (3) (4) (5) (6) (7) (8)

Iliohypogastric nerve Ilioinguinal nerve Lateral femoral cutaneous nerve Genitofemoral nerve Femoral nerve Obturator nerve Sciatic nerve Pudendal nerve

L1 L1 L2-3 L1-2 L2,3,4 L2,3,4 L4-S2 S2,3,4

(1) Lateral cutaneous branch of subcostal nerve (2) Femoral branch of genitofemoral nerve (3) Lateral femoral cutaneous nerve (4) Anterior femoral cutaneous nerves (5) Obturator nerve (6) Common fibular nerve

(7) (8) (9) (10) (11) (12) (13) (14)

Saphenous nerve Superficial fibular nerve Sural nerve Deep fibular nerve Posterior cutaneous nerve of thigh Sural nerve Calcaneal branch of tibial nerve Plantar branches of tibial nerve



Lumbar plexus block Indications: Analgesia for fractured neck of femur and femoral shaft With GA provides analgesia for hip, knee and femoral shaft surgery With sciatic nerve block - anaesthesia & analgesia for all leg & foot surgery Landmarks: Posterior superior iliac spines (PSIS), line joining the iliac crests (Tuffier’s line) Technique: (See Figures 61 & 62) • Patient lateral with operative side uppermost • Draw line parallel to the spinous processes passing through the PSIS. Mark a point where Tuffier’s line crosses Needle: 100-150mm insulated Direction: Perpendicular to skin, slight caudad angle, contact with transverse process (TP) then re-angle to pass above or below TP Depth: 8-12cm Stimulation: Quadriceps contraction If hamstrings are stimulated needle is too medial or too caudad Volume: Approx 0.5 mls/kg - max 30mls LA: 1% Prilocaine , 1% Lidocaine 0.25% - 0.5% Levobupivacaine Complications: Accidental epidural spread leading to bilateral sympathetic, motor and sensory block. Intravascular injection Clinical tips: Avoid medial angulation as paravertebral injection has a high incidence of epidural spread Primarily intramuscular injection - caution high doses of LA can lead to absorption toxicity When combining sciatic nerve blocks with lumbar plexus or femoral nerve blocks - a large combined volume of LA is used, care that the max recommended dose is not exceeded 1 2 L4

6

3 4 5

(1) (2) (3) (4)

Obturator nerve Genitofemoral nerve Femoral nerve Lateral femoral cutaneous nerve (5) Ilioinguinal/iliohypogastric nerves (6) Psoas muscle

FIGURE 61: Lumbar plexus block

(1) Tuffiers line (2) Posterior Superior Iliac Spine (3) Lumbar plexus

1

2 3

FIGURE 62: Lumbar plexus anatomy FIGURE 60: Cross section through L4



Sacral plexus block (parasacral approach) Indications: Post operative analgesia for hip surgery / post amputation, also see indications for sciatic block Landmarks: PSIS, Ischial tuberosity (IT) Technique: (See Figures 63 & 64) • In lateral recumbent position, draw a line connecting the PSIS and IT, at a point 6cm (three fingers breadth) distal to the PSIS Needle: 100mm insulated needle Direction: Perpendicular to skin, to contact bone (sacral ala or ileum) superior aspect of greater sciatic notch, (note depth), redirect needle caudally advancing no more than a further 2cms. Depth: 60-80mm Stimulation: Plantar flexion of the foot/toes (tibial nerve) - accept Dorsiflexion/eversion of the foot (common fibular/peroneal nerve) move needle medially Volume: 10-20mls LA: 0.25-0.5% levobupivacaine Side effects: Blockade of other components of sacral plexus, including posterior cutaneous nerve of thigh, obturator, gluteal nerves and the nerve to quadratus femoris (supplying the hip joint). The sacral parasympathetics, perineal and pudendal nerves may be blocked causing urinary retention (uncommon). Complications: Intravascular injection (internal iliac vessels), perforation pelvic viscera (sigmoid colon) Caution: Avoid adrenaline containing solutions near the sciatic nerve. Blood supply may be damaged. When combining sciatic nerve blocks with lumbar plexus or femoral nerve blocks - a large combined volume of LA is used, care that the max recommended dose is not exceeded

1

2 6cm

FIGURE 63: Parasacral block

(1) Posterior superior iliac spine (2) Ischial tuberosity

1

6 cm

(3) Sacral plexus

2

3

FIGURE 64: Parasacral anatomy



Sciatic nerve block Indications: Solely - ankle and foot surgery. Post-operative analgesia for lower limb amputation. In combination with femoral nerve block for all surgery of the knee and lower leg including amputations 2

Posterior Approach (Labat) Landmarks: Posterior Superior Iliac Spine (PSIS), Greater Trochanter (GT), Ischial Tuberosity (IT), Sacral Hiatus (SH) Technique: • With the patient in Sim’s position, operative leg uppermost • Draw a line connecting the PSIS to the GT, dropping a perpendicular from its mid-point • Mark where this crosses a line joining the sacral hiatus and GT Needle: 100mm insulated needle Direction: Perpendicular to the skin Depth: 50-100mm Stimulation: Plantar flexion of the foot/toes (tibial nerve) - accept Dorsiflexion/eversion of the foot (common fibular/peroneal nerve) - move needle medially Volume: 10-20mls LA: 1% Prilocaine , 1% Lidocaine 0.25% -0.5% Levobupivacaine

1

FIGURE 65: Labat’s approach to sciatic nerve

(1) PSIS (2) Greater trochanter

(3) Sacral hiatus

2

Caution: Avoid adrenaline containing solutions near the sciatic nerve. Blood supply may be damaged. When combining sciatic nerve blocks with lumbar plexus or femoral nerve blocks - a large combined volume of LA is used, care that the max recommended dose is not exceeded. Clinical tips: Place knee in line with PSIS and GT. If unable to stimulate nerve move needle along the perpendicular line (sciatic nerve must cross this line).

1

3

FIGURE 66: Labat’s approach to sciatic nerve



Sciatic nerve block Anterior approach (Beck) Indications: As with other approaches Landmarks: Anterior superior iliac spine (ASIS), pubic tubercle(PT), greater trochanter (GT) Technique: (See Figures 67 & 68) • Draw a line connecting the ASIS to the pubic tubercle • Draw a further parallel line from the greater trochanter • Drop a perpendicular line from the junction of the middle and medial thirds • Mark where the second and third lines cross Needle: 100mm insulated Direction: Directly posteriorly with slight lateral intent - touch the medial aspect of femur - redirect to pass medially - a further 2-3 cms. (See figs 70 page 77 anterior and lateral approaches) Depth: 80-100mm Stimulation: As with other approaches Volume: 10 - 20mls LA: 1% Lidocaine, 1% Prilocaine 0.25% -0.5% Levobupivacaine Side effects: Nil of note Complications: Femoral vessel damage, accidental intravascular injection, nerve damage Clinical tips: The sciatic nerve is two distinct nerves, tibial and common peroneal (fibular) they can divide anywhere in the thigh, but always bear the same relationship, tibial- medial, fibular (peroneal) -lateral The more distal the sciatic block the more likely the risk of missing the posterior cutaneous nerve of thigh. Put non dominant hand under the buttock with a finger on the ischial tuberosity. Aim the stimulating needle 1-2 cm lateral to this finger. Caution: Avoid adrenaline containing solutions near the sciatic nerve. Blood supply may be damaged. When combining sciatic nerve blocks with lumbar plexus or femoral nerve blocks - a large combined volume of LA is used, care that the max recommended dose is not exceeded

6

1

5

FIGURE 67: Anterior approach to sciatic nerve

(1) Anterior Superior Iliac Spine (2) Femoral nerve (3) Pubic tubercle

(4) Sciatic nerve (5) Greater trochanter (6) Femoral artery

1 2

1

⁄3 1

⁄3 1

⁄3

5 3 4

FIGURE 68: Anterior approach to sciatic nerve



Sciatic nerve block Lateral approach The sciatic nerve can also be approached laterally at more than one level as it passes through the thigh Technique: • Marking the posterior border of the greater trochanter, drawing a line parallel to the femur distally

High approach • At the level of the ischial tuberosity (IT)

Mid-thigh approach (See Figures 69 & 70) • Half way between knee and greater trochanter Needle: 100-150mm insulated needle Direction: Horizontally, if femur is contacted, either redirect posteriorly or move insertion point slightly more posteriorly. High approach - aim for IT. Low approach - rotation of thigh to neutral helps location of tibial component. Depth: 8-12cm (high approach), 5-10cm (mid-thigh) Stimulation: as previous page Volume: 10-20 mls LA: 0.25-0.5% Levobupivacaine Clinical tips: The sciatic nerve is two distinct nerves, tibial and peroneal (fibular), they can divide anywhere in the thigh, but always bear the same internal relationship, tibial- medial, fibular- lateral. Probably best to obtain plantar flexion (tibial twitch) for best effect Blockade of the sciatic nerve at mid thigh level will not block the posterior cutaneous nerve of thigh - tourniquet discomfort.

FIGURE 69: Lateral approach

(1) Femoral vessels (2) Femur (3) Sciatic nerve

Caution Avoid adrenaline containing solutions near the sciatic nerve. Blood supply may be damaged. When combining sciatic nerve blocks with lumbar plexus or femoral nerve blocks - a large combined volume of LA is used, care that the max recommended dose is not exceeded

1

2 3

Medial

FIGURE 70: Anterior and lateral approach



Sciatic nerve block Inferior approach (Raj) Indications: As with other approaches Landmarks: Greater trochanter (GT), ischial tuberosity (IT) Technique: (See Figures 71 & 72) • With the patient supine, flex the knee to 90 degrees • Draw a line connecting the GT to the IT • Mark a point half way in the groove between the hamstring and adductor muscles Needle: 50-100mm insulated Direction: Perpendicular to skin, slight medial intent Depth: 40-80 mm Volume: 10-20 mls LA: 1% Lidocaine, 1% Prilocaine 0.25% - 0.5% Levobupivacaine Stimulation: As for posterior approach Side effects and Complications: As for other approaches

2

1

FIGURE 71: Sciatic nerve block - inferior approach

(1) Ischial tuberosity (2) Greater trochanter

1 2

FIGURE 72: Sciatic nerve anatomy



Femoral nerve block Indications: Solely - analgesia for fractured femoral shaft, post-op analgesia after knee surgery Combination with sciatic- for knee and lower leg surgery with or without GA Landmarks: Inguinal ligament, femoral artery (See Figures 73, 74 & 75) Technique: • At a point 1cm below the inguinal ligament and 1cm lateral to the femoral artery Needle: 50mm insulated/uninsulated Direction: 45º proximal Depth: 30-50mm Two distinct “pops” may be felt (fascia lata, fascia iliacus/pectineus) Stimulation: Patellar twitch Volume: 10-15mls (isolated femoral nerve) 20-30mls (femoral and lateral cutaneous nerve of thigh) “2 in 1 block”. Note that the obturator nerve can not be reliably blocked by this route LA: 1% Prilocaine, 1% Lidocaine 0.25% -0.5% Levobupivacaine Complications: Vascular puncture Inadvertent intravascular injection Clinical tips: Sartorius twitch - too superficial Keep close to the inguinal ligament as the femoral nerve divides soon after this.

FIGURE 74: Femoral nerve block

(1) (2) (3) (4)

Anterior Superior Iliac Spine Lateral cutaneous nerve of thigh Femoral nerve Femoral artery

(5) Femoral vein (6) Inguinal ligament (7) Pubic tubercle

2

1

3 3

4

5

6

7

4 5 6

1

7

2

8

FIGURE 73: Cross section of femoral triangle

(1) (2) (3) (4)

Sartorius muscle Iliopsoas Fascia lata Fascia iliacus/pectineus

(5) (6) (7) (8)

Femoral nerve Femoral artery Femoral vein Pectineus

FIGURE 75: Femoral triangle anatomy



Lateral cutaneous nerve of thigh block 1

2cm 2cm

Indications: Anaesthesia lateral thigh (hip/femoral operations) Landmarks: ASIS, inguinal ligament. Technique: • At a point 2cms medial / 2cms inferior to the ASIS (below the inguinal ligament) Needle: 21- 23G 50mm uninsulated Direction: Perpendicular to skin Depth: 1-3cm Endpoint: Click as the fascia lata is pierced (infiltrate above and below the fascia lata) Volume: 10mls in total LA: 1% Lidocaine, 1% Prilocaine 0.25% Levobupivacaine Complications: Accidental femoral nerve block

FIGURE 76: Lateral femoral cutaneous nerve block

(1) Anterior superior iliac spine (2) Lateral cutaneous nerve of thigh (3) Femoral nerve

1

2 cm 2 cm 3

2

FIGURE 77: Lateral cutaneous nerve of thigh anatomy



Knee/popliteal blocks Indications: Ankle and foot surgery

Lateral popliteal approach Landmarks: Patella, biceps femoris, vastus lateralis Technique: • Flex the knee • Identify vastus lateralis above and the tendon of biceps femoris below • Mark the groove between, drop a line from the superior border of the patella • Mark the point of intersection (See Figure 78, 79 & 80) Needle: 50mm insulated Direction: 15º caudad, 30º posterior Depth: Common peroneal (fibular) 10-20mm, tibial 30-50mm Stimulation: Tibial - plantar flexion of foot Common peroneal (fibular) - dorsiflexion/eversion of foot Volume: 10-15 mls at each nerve LA: 1% Lidocaine, 1% Prilocaine 0.25%-0.5% Levobupivacaine

FIGURE 79: Popliteal block - lateral approach

(1) (2) (3) (4) (5)

Patella Vastus lateralis Femur Biceps femoris Lateral head of gastrocnemius

(6) (7) (8) (9)

Common fibular nerve Tibial nerve Semimembranosus Semitendinosus

2 1

1

Medial

3

Lateral 1

4

c/s 5

2 6

3

5

4

6

8

7

FIGURE 78: Popliteal fossa

(1) Semimembranosus (2) Semitendinosus (3) Biceps femoris

9

(4) Popliteal artery (5) Tibial nerve (6) Common fibular nerve

FIGURE 80: Cross section at level of patella



Knee/popliteal blocks Prone posterior approach

Supine posterior approach

Landmarks: Semimembranosus, biceps femoris and the popliteal crease. Technique: • With the patient prone and the leg resting on a pillow, flex the knee, mark the popliteal crease • Palpate the apex of the fossa, marking the boundaries (lateral - biceps femoris, medial - semimembranosus) • Draw a line from the apex to the middle of the popliteal crease • Mark a point 6cm - 8cm proximal to the crease and 1cm lateral

Technique: • With the patient supine, flex the knee and hip to 90º, asking an assistant to support the leg • Identify the borders & apex of the popliteal fossa • Mark a point, 1cm lateral to the midline and 6-8cm proximal to the popliteal crease

(See Figure 78 & 81)

Needle: Direction:

50-80mm insulated 45º proximal, moving laterally to identify tibial then common fibular (peroneal) Depth: 30-80mm Stimulation: Tibial - plantar flexion of foot Common fibular (peroneal) - dorsiflexion/eversion of foot Volume: 10-15 mls at each location LA: 1% Lidocaine, 1% Prilocaine 0.25%-0.5% Levobupivacaine Side effects: Nil of note Complications: Vascular puncture Clinical tip: 75% of sciatic nerves divide within 10cm of the popliteal crease. If fine movements of the needle cause both fibular and tibial nerves to be stimulated assume nerves are close enough together to use a single 20 - 30 ml injection of LA

FIGURE 81: Popliteal block - Prone posterior approach


Needle: Direction:

50-80mm insulated Perpendicular to skin, moving laterally to identify tibial then common fibular (peroneal). Depth: 40-80mm Stimulation: Tibial - plantar flexion of foot Common fibular (peroneal) - dorsiflexion/eversion of foot Volume: 10-15 mls at each location LA: 1% Lidocaine, 1% Prilocaine 0.25%-0.5% Levobupivacaine Side effects: Nil of note Complications: Vascular puncture

FIGURE 82: Popliteal block - Supine posterior approach



Intra-articular knee block

Saphenous nerve block

Indications: Arthroscopy/postoperative analgesia Landmarks: Lateral border of patella Technique: • With the knee extended, palpate the lateral border of the patella, inserting a needle just beneath the patella into the joint Needle: 19-21G 35mm Endpoint: Withdraw synovial fluid, easy injection Volume: 20-30mls LA: 1% Lidocaine, 0.25%-0.5% Levobupivacaine with/without 1:200,000 Adrenaline Clinical tips: Always perform intra-articular injections under strict asepsis Infiltrate arthroscope portals with Lidocaine + Adrenaline This technique can only be use without a tourniquet Following arthroscopy, injection may be repeated (as original LA is washed out), opiate may be added ie: morphine / diamorphine

Indications: Ankle and foot surgery (in addition to popliteal block - tibial + fibular nerves) Incisions over the antero-medial aspect of the lower leg Landmarks: Tibial tubercle, medial condyle of the tibial Technique: (See Figures 84 & 85) • Draw a line joining the tibial tubercle to medial condyle of the tibia, infiltrated subcutaneously along this line Volume: 10-20 mls LA: 1% Prilocaine, 1% Lidocaine 0.25% Levobupivacaine Side effects: Nil Complications: Bleeding (long saphenous vein)

FIGURE 84: Saphenous nerve block

(1) Saphenous nerve (2) Saphenous vein 2

1

FIGURE 83: Intra-articular knee block FIGURE 85: Saphenous nerve anatomy



Ankle and foot Indications: Forefoot and toe surgery Landmarks: Dorsalis pedis (DP), posterior tibial artery, medial malleolus and sustentaculum tali Technique:

3

5

Deep fibular (peroneal) nerve: (See Figure 92) • 2-3 cm distal to the inter-malleolar line palpate the Dorsalis Pedis artery. Insert a 23-25G needle - medial & lateral to DP to bone, inject 2mls on each side

2

Superficial fibular (peroneal) nerve:

4

• From the above point, infiltrate subcutaneously laterally and medially across the dorsum of the foot to dorsum/plantar junction Volume: 6-10mls 2

4

6

Tibial nerve: • Draw a line joining the medial malleolus to the posterior inferior border of the calcaneum • Mark a point just posterior to the posterior tibial pulse (half way) Needle: 25-50 mm Stimulation: Plantar-flexion toes, paraesthesia to the sole of foot/toes Volume: 5-8mls

3

1 1

Sural nerve: • Infiltrate subcutaneously from lateral malleolus to lateral border of Achilles tendon Volume: 5mls Clinical Tips: Use in conjunction with an ankle tourniquet for all minor foot surgery Painful block in non-anaesthetised patient - sedation advised.

Sustentaculum Tali (ST) injection (Alternative approach to Tibial Nerve): • Palpate ST, prominence directly inferior to medial malleolus • Insert 25G needle to pass beneath ST - depth 25mm - inject 5mls LA

FIGURE 86: Cutaneous innervation of foot and ankle

(1) Medial and lateral plantar (tibial) - sole of foot (2) Tibial nerve (calcaneal) - heel (3) Saphenous nerve (femoral) - medial side of foot variable innervation to head of 1st metatarsal (4) Sural (fibular) - lateral margin of foot and fifth digit (5) Superficial fibular (peroneal) nerve - dorsum of foot (6) Deep fibular nerve - web between 1st and 2nd toe



Lateral 1

2 1

3

4

FIGURE 88: Tibial block 5

(1) Posterior tibial artery (2) Tibial nerve

(3) Medial malleolus (4) Calcaneal branch of tibial nerve

6

1

2

FIGURE 87: Cross section ankle

(1) Deep fibular (peroneal) nerve (2) Talus (3) Fibula

(4) Tibia (5) Medial & lateral plantar nerves (6) Sural nerve

3

4

FIGURE 89: Medial ankle



FIGURE 90: Sural nerve

FIGURE 92: Deep fibular nerve block

1

(1) (2) (3) (4)

Small saphenous vein Sural nerve Lateral malleolus Achilles tendon

1 2 3 4

2

5 3

4

FIGURE 91: Lateral ankle

FIGURE 93: Dorsal foot

(1) (2) (3) (4) (5)

Superficial fibular nerve Saphenous nerve Extensor hallucis longus Deep fibular nerve Dorsalis pedis artery



Mid Tarsal Indication: Post-op pain control. Minor surgery of the forefoot or toes. Use in conjunction with an ankle tourniquet Technique: (See Figures 94 & 95) • Palpate the metatarsophalangeal joint (MTPJ). Mark a point 2cm proximal to the MTPJ Needle: Insert a 21-23G needle either side of the metatarsal to plantar aspect of foot. Inject 6-8mls while withdrawing needle LA: 1% Prilocaine, 1% Lignocaine 0.5% Levobupivacaine Side effects: Pain with injection Complications: Haematoma Clinical tips: There will be no appreciable motor block

Digital nerve block and webspace block See pages 50-53 for similar blocks for the fingers

FIGURE 94: Mid tarsal injection

(1) Metatarsals (2) Digital nerves

1 1 1

1 1

2

FIGURE 95: Mid tarsal anatomy

SECTION SIX Practical application of peripheral nerve blocks

SECTION SIX / PRACTICAL APPLICATION / 99

Anaesthesia / analgesia for major joint surgery / replacement Shoulder Cutaneous innervation Anterior/Posterior-supraclavicular nerves (superficial cervical plexus - C3-4), Intercostobrachial nerve T2 Laterally over deltoid insertion - axillary nerve C5-6 Joint Suprascapular nerve (superior trunk C5-6) Axillary nerve (posterior cord C5-6) Lateral pectoral nerve (lateral cord C5-7) Analgesia - Suprascapular nerve block +/-superficial cervical plexus block Anaesthesia / analgesia - Interscalene brachial plexus block Catheter techniques for extended analgesia / physiotherapy Clinical tips Supraclavicular/infraclavicular brachial blocks seldom block suprascapular nerve.

Elbow Cutaneous innervation Medial cutaneous nerve of arm /forearm (medial cord C8-T1) Posterior cutaneous nerves of arm / forearm (radial nerve -posterior cord C5-8 +T1) Lateral cutaneous nerve of forearm (lateral cord C5-7) Joint Primarily by the musculocutaneous (C5-7), radial (C5-8, T1) and ulnar nerve (C7,8,T1) Anaesthesia / analgesia - brachial plexus block (supra / infraclavicular, axillary and midhumeral) Catheter techniques for extended analgesia (supra / infraclavicular & axillary Clinical tips To ensure adequate cutaneous anaesthesia (axillary & midhumeral approaches) cutaneous infiltration of medial cutaneous nerve of arm needs to be added (nerve lies outside of sheath).

Wrist Cutaneous innervation Medial cutaneous nerve of forearm Posterior cutaneous nerve of forearm Lateral cutaneous nerve of forearm Cutaneous branches of the median, ulnar and radial Joint Anterior interosseous nerve (median) Posterior interosseous nerve (radial) Dorsal and deep branches of the ulnar nerve Anaesthesia / analgesia Supraclavicular, Infraclavicular, axillary or midhumeral (interscalene - often misses lower roots, ulnar border wrist and hand) Clinical tips Bier’s block (IVRA) suitable for minor superficial operations or ‘K’ wires.

100 / SECTION SIX / PRACTICAL APPLICATION


Hand

Hip 2

3

2 5

3

4

1

Cutaneous innervation Lower intercostal nerves- subcostal (T12) ilio-hypogastric (L1) Lateral cutaneous nerve of thigh (lumbar plexus L2-3) Superior cluneal nerve (dorsal rami L1-3) Joint innervation Femoral nerve (L2-4 - branch to rectus femoris) Obturator nerve (L3-4 - anterior divisions) Sciatic nerve (L4-S3 - nerve to quadratus femoris) Superior gluteal nerve (L4-S1) Analgesia - Lumbar plexus block - posterior or anterior +/- parasacral block Anaesthesia - difficult to obtain complete surgical anaesthesia due to multiple innervations and varied surgical approaches Catheter techniques can be used for extended analgesia i.e lumbar plexus block for femoral shaft fractures Clinical tips Complete anaesthesia / analgesia is best obtained with either spinal or epidural techniques

Knee

FIGURE 96: Cutaneous innervation of hands

Cutaneous innervation 1. Palmar cutaneous branch of the median nerve - skin lateral palm/thenar eminence 2. Medial/lateral branches of the median nerve - skin palmar surface, dorsum of terminal digits & nail beds of radial 31/2 digits. 3. Superficial branch ulnar nerve - skin of ulnar 11/2 digits. 4. Palmar cutaneous nerve of ulnar - skin over medial palm and hypothenar eminence 5. Superficial branch radial nerve - skin over dorsum of hand thumb and lateral aspect. Analgesia and analgesia Wrist blocks are sufficient with a wrist tourniquet for most minor surgery. Complete anaesthesia and immobility - midhumeral, axillary and infraclavicular approaches to the brachial plexus. Surgery isolated to digits - web space or digital nerve block Bier’s block sufficient for all minor hand surgery + minor bone work MUA + K wires. Clinical tips Palmar cutaneous branches of both ulnar and median leave their respective nerve proximal to the wrist - ulnar mid forearm, median proximal to flexor retinaculum passing superficial to it. Cutaneous innervation in the hand is very variable

Cutaneous innervation Femoral and saphenous nerve (L2-4) Posterior femoral cutaneous nerve (S2-3 - sacral plexus) Common fibular nerve (sural cutaneous nerve) Joint innervation Branches from femoral, obturator, tibial and common fibular nerves Analgesia - lumbar plexus block - posterior/anterior Anaesthesia - lumbar plexus + sciatic nerve +/- obturator Catheter techniques for extended analgesia Clinical tips Anaesthesia for arthroscopy can be achieved with intra-articular LA + infiltration of portals. For tourniquet add femoral nerve block. Sciatic and femoral blocks provide good analgesia but are not suitable as sole technique for knee replacement unless combined with light GA

Ankle Cutaneous innervation Saphenous nerve Superficial fibular (peroneal) nerve Sural nerve (arises from both tibial and common fibular nerve) Tibial nerve Joint innervation Tibial nerve and deep fibular nerve Analgesia/anaesthesia - sciatic nerve block (above the knee) or tibial + common fibular nerve (popliteal approach). Clinical tips Saphenous nerve should be included for all medial ankle operations Thigh tourniquet required - proximal sciatic nerve and femoral nerve block


Foot

3

5 4

2 4

6 3

1 1

FIGURE 97: Cutaneous innervation of foot

Cutaneous innervation 1) Medial and lateral plantar (tibial) - sole of foot 2) Tibial nerve (calcaneal) - heel 3) Saphenous nerve (femoral) - medial side of foot, variable innervation to head of the first metatarsal 4) Sural (fibular) - lateral margin of foot and fifth digit 5) Superficial & deep fibular nerves - dorsum of foot 6) Deep fibular nerve - web between 1st and 2nd toe Analgesia and analgesia Deep and superficial peroneal / fibular nerves + tibial nerve (behind medial malleoli) sufficient for most toe surgery/ except little toe (sural nerve)- use in conjunction with ANKLE tourniquet, Complete anaesthesia / immobile foot - tibial + common fibular (popliteal block) + saphenous nerve block If high tourniquet required - proximal sciatic nerve + femoral nerve block. Clinical tips The foot is not immobile following an ankle block Ankle blocks are uncomfortable to perform on awake patients - use sedation.



Catheter techniques

Commercially available kits

Advantages Extension of anaesthesia and analgesia into the post operative period - 24-72hrs Extended physiotherapy - frozen shoulder, complex regional pain syndromes (CRPS) 72hrs - 7days Disadvantages Technically more difficult to perform, larger needles, non standardisation of kit High failure rate - greater then 25% Labour intensive ie. Top ups, infusion pumps and nurse monitoring General principles • Catheter needs to ideally lie parallel/alongside the nerve or plexus being blocked • Therefore needle should be inserted as near to parallel to the nerve / plexus as possible to facilitate this • Not so important when using Tuohy needle as catheter comes out at right angles to the needle direction- in theory (in practice 45º) • Prior to passing catheter, distend the space with 10-20mls of saline or local anaesthetic • Only thread 3-5cms of catheter into space (unless using stimulating catheter – then thread to target) • Always flush the catheter after insertion - avoids blockage with blood • Securely fix catheter (falling out! commonest cause of failure)

Cannula over needle - Catheter through cannula Advantages Cheap, smaller needle Disadvantages High failure rate • Needle is the only reliable indicator of position - stimulating nerve • When cannula is advanced off needle NO guarantee it will lie next to nerve (cannula needs to be advanced millimetres not centimetres otherwise it will kink) • Cannula is often damaged by needle making it impossible to thread catheter • Catheter often difficult to thread, lack of rigidity - use 18G epidural catheter- this is stronger, less floppy

Catheter through needle - Tuohy / Sprotte / Faceted tip Advantages Catheter placed at site of stimulation, more reliable placement Disadvantages Needle size (18G)

Stimulating catheter Advantages Reliable placement of catheter stimulating chosen nerve or plexus. Confirm position of catheter prior to bolus of local anaesthetic i.e. stimulating C5/6 for shoulder replacement Check catheter position during post-operative period and reposition as necessary (withdraw slightly) Disadvantage Can be uncomfortable to place in awake patients, as saline must be used to distend space rather than LA Stimulating catheter is fairly stiff, can cause pain/paraesthesia on insertion Cost


Suggested regimes / postoperative care All catheters need their position (non vascular/perineurally) and effect (anaesthesia /analgesia of the target plexus / nerve) confirmed prior to commencing infusion or bolus dosing Therefore • If performing regional block before threading catheter - use short acting LA (Lidocaine /Prilocaine) for block & long acting LA (Levobupivacaine) through catheter - if anaesthesia lasts longer than 4hrs - greater likelihood catheter is in the correct place. • Always bolus catheter with a volume large enough to exclude intravascular placement (+/-adrenaline) prior to commencing continuous infusion, • Allow block to wear off prior to bolusing &/or commencing infusion - guarantees position and effect

Bolus top-ups Brachial plexus / Lumbar plexus catheters Levobupivacaine 0.25% 20-30mls - 6-12hrs Bolus injections should always be carried out in a controlled environment with resuscitation equipment available

Continuous infusions Brachial plexus / Lumbar plexus catheters Levobupivacaine 0.25% Levobupivacaine 0.1% +/- Fentanyl 2mcg/ml

108 / NOTES

NOTES

Equal efficacy and lower toxicity than bupivacaine 1

Licensed indications and dosage guidelines 2 Licensed indications

Adults

Epidural – post-operative pain

150 mg

18.75 mg/hr

Epidural – obstetrics

150 mg

12.5 mg/hr

15 mg

N/A

150 mg

400 mg/24hrs

112.5 mg

N/A

150 mg

400 mg/24hrs

2.5 mg/kg

N/A

Intrathecal Peripheral nerve block Ophthalmic blocks Local infiltration

Children

Preparations available:

Recommended max multiple dose or infusion

Recommended max single dose

Ilioinguinal/ Iliohypogastric blocks

2.5 mg/ml 5.0 mg/ml 7.5 mg/ml

Why take the risk? levobupivacaine HCI Prescribing information can be found on reverse

Chirocaine (Levobupivacaine Hydrochloride) Prescribing Information. Presentation: Three strengths are available, 2.5 mg/ml, 5.0 mg/ml and 7.5 mg/ml of levobupivacaine as levobupivacaine hydrochloride. Each strength is available in 10ml polypropylene ampoules in packs of 10. Indications: Adults: Surgical anaesthesia - Major, e.g. epidural (including for Caesarean section), intrathecal, peripheral nerve block - Minor, e.g. local infiltration, peribulbar block in ophthalmic surgery. Pain management - Continuous epidural infusion, single or multiple bolus epidural administration for the management of pain especially post-operative pain or labour analgesia. Children: analgesia (ilioinguinal/iliohypogastric blocks). Dose and Administration: The precise posology will depend upon the procedure and individual patient concerned. Careful aspiration before and during injection is recommended to prevent intravascular injection. When a large dose is to be injected, e.g. in epidural block, a test dose of 3-5 ml lidocaine (lignocaine) with adrenaline is recommended. An inadvertent intravascular injection may then be recognised by a temporary increase in heart rate and accidental intrathecal injection by signs of a spinal block. Aspiration should be repeated before and during administration of a bolus dose, which should be injected slowly and in incremental doses, at a rate of 7.5 30 mg/min, while closely observing the patient’s vital functions and maintaining verbal contact. The recommended maximum single dose is 150 mg. The maximum recommended dose during a 24 hour period is 400 mg. For Post-operative pain management, the dose should not exceed 18.75 mg/hour. For Caesarean section, higher concentrations than the 5.0 mg/ml solution should not be used. For labour analgesia by epidural infusion, the dose should not exceed 12.5 mg/hour. In children, the maximum recommended dose for analgesia (ilioinguinal/iliohypogastric blocks) is 1.25 mg/kg/side. Contra-indications: Patients with a known hypersensitivity to local anaesthetic agents of the amide type; intravenous regional anaesthesia (Bier’s block); patients with severe hypotension such as cardiogenic or hypovolaemic shock; and use in paracervical block in obstetrics. The 7.5 mg/ml solution is contra-indicated for obstetric use due to an enhanced risk for cardiotoxic events based on experience with bupivacaine. There is no experience of levobupivacaine 7.5 mg/ml in obstetric surgery. Precautions: Epidural anaesthesia with any local anaesthetic may cause hypotension and bradycardia. All patients must have intravenous access established. The availability of appropriate fluids, vasopressors, anaesthetics with anticonvulsant properties, myorelaxants, atropine, resuscitation equipment and expertise must be ensured. Levobupivacaine should be used with caution for regional anaesthesia in patients with impaired cardiovascular function e.g. serious cardiac arrhythmias and in patients with liver disease or with reduced liver blood flow e.g. alcoholics or cirrhotics. Interactions: Metabolism of levobupivacaine may be affected by CYP3A4 inhibitors eg: ketoconazole and CYP1A2 inhibitors eg: methylxanthines. Levobupivacaine should be used with caution in patients receiving anti-arrhythmic agents with local anaesthetic activity, e.g., mexiletine, or class III anti-arrhythmic agents since their toxic effects may be additive. No clinical studies have been completed to assess levobupivacaine in combination with adrenaline. Side-Effects: Adverse reactions with local anaesthetics of the amide type are rare, but they may occur as a result of overdosage or unintentional intravascular injection and may be serious. Accidental intrathecal injection of local anaesthetics can lead to very high spinal anaesthesia possibly with apnoea, severe hypotension and loss of consciousness. The most frequent adverse events reported in clinical trials irrespective of causality include hypotension (22%), nausea (13%), anaemia (11%), postoperative pain (8%), vomiting (8%), back pain (7%), fever (6%), dizziness (6%), foetal distress (6%) and headache (5%). Other side effects include: CNS effects: numbness of the tongue, light-headedness, dizziness, blurred vision and muscle twitch followed by drowsiness, convulsions, unconsciousness and possible respiratory arrest. CVS effects: decreased cardiac output, hypotension and ECG changes indicative of either heart block, bradycardia or ventricular tachyarrhythmias that may lead to cardiac arrest. Neurological damage is a rare but well recognised consequence of regional and particularly epidural and spinal anaesthesia. This may result in localised areas of paraesthesia or anaesthesia, motor weakness, loss of sphincter control and paraplegia. Rarely, these may be permanent. Use in Pregnancy and Lactation: Levobupivacaine should not be used during early pregnancy unless clearly necessary. The clinical experience of local anaesthetics of the amide type including bupivacaine for obstetrical surgery is extensive. The safety profile of such use is considered adequately known. There are no data available on excretion of levobupivacaine into human breast milk. However, levobupivacaine is likely to be transmitted in the mother’s milk, but the risk of affecting the child at therapeutic doses is minimal. Overdose: Accidental intravascular injection of local anaesthetics may cause immediate toxic reactions. In the event of overdose, peak plasma concentrations may not be reached until 2 hours after administration depending upon the injection site and, therefore, signs of toxicity may be delayed. Systemic adverse reactions following overdose or accidental intravascular injection reported with long acting local anaesthetic agents involve both serious CNS and CVS effects. Special Storage Conditions: No special storage precautions for the closed ampoule. Once opened, use immediately. Legal Category: POM. Marketing Authorisation Number: PL 0037/0300-0302. Basic NHS Price: 2.5 mg/ml pack: £16.60, 5.0 mg/ml pack: £19.00, 7.5mg/ml pack: £28.50. Further information is available on request from Abbott Laboratories Ltd, Abbott House, Norden Road, Maidenhead, Berkshire SL6 4XE. PI/93/1/001. References: 1. Burke D, Bannister J. Current Anaesthesia and Critical Care 1999; 10:262-269. 2. Chirocaine Summary of Product Characteristics.

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