Paravertebral Block

Quick Answer

Paravertebral block (PVB) involves injection of local anaesthetic into the paravertebral space lateral to the vertebral column where spinal nerves exit the intervertebral foramina, providing unilateral somatic and sympathetic blockade of multiple contiguous dermatomes. Anatomy: Wedge-shaped space bounded medially by vertebral body, intervertebral disc and foramen; laterally by costotransverse ligament and parietal pleura (thoracic) or psoas fascia (lumbar); posteriorly by superior costotransverse ligament; anteriorly by parietal pleura/peritoneum. Indications: Thoracotomy, VATS, breast surgery, rib fractures, unilateral abdominal surgery (nephrectomy, cholecystectomy), chronic pain (post-herpetic neuralgia). Technique: Landmark (loss of resistance when needle passes through costotransverse ligament), ultrasound-guided (visualize transverse process, pleura, spread), or nerve stimulator; 15-20 mL 0.25-0.5% ropivacaine or bupivacaine per level. Advantages: Unilateral (reduces hypotension vs epidural), no lower limb motor block, reduced PONV and urinary retention, opioid-sparing, reduces chronic post-thoracotomy pain. Complications: Pneumothorax (2-5% landmark, <1% ultrasound), vascular injection, epidural spread, intrathecal injection, hypotension. [1-20]

Anatomy

Paravertebral Space

Definition: The paravertebral space is a wedge-shaped potential space located lateral to the vertebral column where spinal nerves exit the intervertebral foramina before dividing into dorsal and ventral rami. It contains the spinal nerve, dorsal root ganglion, sympathetic chain, and communicating rami.

Boundaries:

Medial:

• Vertebral body (posterior aspect)
• Intervertebral disc
• Intervertebral foramen
• Lateral border of vertebral canal

Lateral:

• Thoracic: Costotransverse ligament, internal intercostal membrane, parietal pleura
• Lumbar: Psoas major muscle fascia, quadratus lumborum

Anterior:

• Thoracic: Parietal pleura (endothoracic fascia)
• Lumbar: Psoas major muscle, abdominal viscera/peritoneum

Posterior:

• Thoracic: Superior costotransverse ligament, transverse process
• Lumbar: Erector spinae muscles, transverse process

Superior and Inferior:

• Not bounded: Space communicates with adjacent levels via intervertebral foramina
• Cephalad-caudad spread: Local anaesthetic can spread 3-5 levels from single injection

Contents of Paravertebral Space

Neural Structures:

1. Spinal nerve: Mixed motor, sensory, sympathetic fibers
2. Dorsal root ganglion: Sensory cell bodies
3. Dorsal ramus: Posterior cutaneous branches (innervate skin, muscles of back)
4. Ventral ramus: Continues as intercostal (thoracic) or lumbar plexus (lumbar) nerves
5. Rami communicantes: White (preganglionic sympathetic) and gray (postganglionic) rami connecting to sympathetic chain

Sympathetic Chain:

• Thoracic: Along neck of ribs, anterior to costotransverse ligament
• Lumbar: Along anteromedial border of psoas major
• Function: Block produces unilateral sympathetic denervation

Vascular Structures:

• Segmental arteries: Accompany spinal nerves
• Spinal branches: Supply vertebrae, spinal cord
• Risk: Intravascular injection possible

Lymphatic Structures:

• Segmental lymphatics
• Thoracic duct (left, at T5-T8 level - risk of injury)

Thoracic Paravertebral Anatomy

Vertebral Levels:

• 12 thoracic vertebrae
• 12 intercostal spaces
• 12 thoracic spinal nerves

Surface Anatomy:

• T1-T4: Below corresponding spinous process (oblique course)
• T5-T8: 2-3 cm lateral to spinous process
• T9-T12: 3-4 cm lateral to spinous process

Transverse Process Landmarks:

• T1: Level of C7 spinous process
• T3: Level of spine of scapula
• T7: Inferior angle of scapula
• T12: Level of L1 spinous process

Rib Anatomy:

• Typical ribs (3-9): Neck, tubercle, angle, body
• Relations: Transverse process articulates with tubercle
• Neurovascular bundle: Runs inferior to rib (vein, artery, nerve - VAN)

Costotransverse Ligament:

• Function: Stabilizes rib to transverse process
• Significance: Needle passes through this ligament to enter paravertebral space
• Loss of resistance: Classic landmark technique endpoint

Lumbar Paravertebral Anatomy

Lumbar Plexus:

• L1-L4 ventral rami within psoas major muscle
• Terminal branches: Iliohypogastric, ilioinguinal, genitofemoral, lateral femoral cutaneous, femoral, obturator
• Lumbosacral trunk: L4, joins sacral plexus

Psoas Major Muscle:

• Origin: T12-L5 transverse processes, vertebral bodies, intervertebral discs
• Insertion: Lesser trochanter of femur
• Function: Hip flexion
• Relation: Lumbar plexus within muscle belly

Lumbar Paravertebral Space:

• Anterior: Psoas major muscle
• Posterior: Quadratus lumborum, erector spinae
• Relation to TAP: Continuous with thoracolumbar fascia and transversus abdominis plane

Ultrasound Anatomy

Probe Position (Thoracic):

• Transverse/Oblique: At appropriate vertebral level
• Position: 2-4 cm lateral to midline (spinous process)
• Orientation: Perpendicular to rib/transverse process

Sonographic Appearance:

Superficial:

1. Skin and subcutaneous tissue
2. Erector spinae muscles: Hypoechoic, posterior

Intermediate: 3. Transverse process: Hyperechoic, flat surface, posterior acoustic shadowing 4. Rib (if scanning more lateral): Curved hyperechoic structure with shadowing 5. Pleura: Hyperechoic line deep to transverse process

Target Area: 6. Paravertebral space: Wedge-shaped space between transverse process and pleura 7. Local anaesthetic spread: Visible as anechoic fluid pushing pleura anteriorly

Key Ultrasound Signs:

• Pleural displacement: Anterior displacement confirms correct space
• Cephalad spread: Visualize spread along paravertebral gutter
• Avoid: Intrapleural injection (fluid above pleura), intrathecal (too medial)

Indications and Contraindications

Indications

Thoracic Surgery:

• Thoracotomy: Unilateral thoracotomy (video-assisted or open)
• VATS: Video-assisted thoracoscopic surgery
• Lung resection: Lobectomy, pneumonectomy, wedge resection
• Mediastinal surgery: Thymectomy, mediastinal mass excision
• Chest wall surgery: Rib resection, chest wall tumor

Breast Surgery:

• Mastectomy: Simple, modified radical, skin-sparing
• Lumpectomy: Wide local excision with sentinel node biopsy
• Axillary dissection: Level I/II/III
• Reconstruction: Tissue expander, implant, flap procedures
• Advantage: Reduced chronic postoperative pain vs general anesthesia alone

Rib Fractures:

• Multiple rib fractures: Unilateral flail chest
• Pain management: Reduces opioid requirements, improves ventilation
• Ventilatory support: Facilitates weaning from ventilation
• Physiotherapy: Allows effective chest physiotherapy

Abdominal Surgery:

• Unilateral procedures: Nephrectomy, adrenalectomy
• Cholecystectomy: Unilateral approach (less common with laparoscopic)
• Hernia repair: Unilateral inguinal/femoral
• Splenectomy: Left-sided approach

Chronic Pain:

• Post-herpetic neuralgia: Acute and chronic management
• Complex regional pain syndrome: Upper thoracic for upper limb
• Phantom limb pain: Amputation-related neuropathic pain
• Neuropathic pain: Unilateral trunk pain

Pediatric Applications:

• Thoracotomy: Congenital diaphragmatic hernia repair
• Nuss procedure: Pectus excavatum correction
• Cardiac surgery: Unilateral thoracotomy approaches

Contraindications

Absolute Contraindications:

• Patient refusal: Unable to consent
• Infection at site: Cellulitis, abscess at injection site
• Allergy to local anaesthetics: True allergy (rare)
• Severe coagulopathy: Uncontrolled bleeding disorder
• Raised intracranial pressure: Risk of further increase

Relative Contraindications:

Anticoagulation (ASRA Guidelines):

• Thoracic PVB: Intermediate risk (similar to epidural)
• INR: <1.4 for thoracic
• Platelets: >50,000
• Therapeutic LMWH: Delay 12-24 hours
• DOACs: Hold 2-3 days
• Benefit vs risk: Weigh in post-thoracotomy pain management

Anatomical Concerns:

• Previous thoracic surgery: Scarring, altered anatomy
• Spinal deformity: Kyphoscoliosis makes landmarking difficult
• Severe emphysema: Increased pneumothorax risk
• Pleural adhesions: Reduced space, distorted anatomy
• Tumor infiltration: Distorted anatomy, risk of seeding

Medical Concerns:

• Severe respiratory disease: Bilateral spread risk, compromised ventilation
• Hemodynamic instability: Sympathetic block may worsen
• Contralateral pneumonectomy: Reduced reserve, avoid bilateral spread
• Neurological deficits: Pre-existing, document carefully

Specific Considerations:

• Thoracic duct: Left-sided T5-T8 blocks risk thoracic duct injury (chyle leak)
• Diaphragmatic paresis: Phrenic nerve involvement possible (cervical/thoracic)
• Horner's syndrome: Cervical/thoracic blocks (T1-T2)

Technique

Pre-Block Assessment

Mandatory Checks:

1. Informed consent with risks explained (pneumothorax, vascular injury, epidural spread)
2. Medical history (respiratory disease, coagulation status)
3. Physical examination (baseline neurological function)
4. Review imaging (CXR, CT if prior thoracic surgery)
5. Monitoring: ECG, NIBP, SpO2
6. IV access (large bore if thoracic)
7. Lipid emulsion available
8. Equipment for chest drain insertion (if thoracic)

Landmark Technique (Thoracic)

Patient Position:

• Sitting (preferred): Easier to identify landmarks
• Lateral decubitus: Operative side up
• Prone: Less common

Surface Landmarks:

1. Identify spinous process of target level
2. Mark 2.5-3 cm lateral to superior border of spinous process
3. Identify transverse process depth (usually 3-5 cm)

Needle Insertion:

• Needle: 80-120 mm, 22G
• Direction: Perpendicular to skin, slightly cephalad
• Advance until contact with transverse process (3-5 cm typically)
• Withdraw slightly, redirect cephalad, walk off superior edge of transverse process
• Advance 1 cm deeper (penetrates costotransverse ligament)
• Loss of resistance: Classic endpoint

Loss of Resistance Technique:

• Attach syringe with saline or air
• Advance needle slowly with pressure on plunger
• Sudden loss of resistance = entry into paravertebral space
• Aspirate (no blood, no air, no CSF)
• Inject 15-20 mL local anaesthetic

Catheter Insertion:

• Thread catheter 3-5 cm beyond needle
• Secure with tunneling and adhesive dressing
• Test dose before infusion

Ultrasound-Guided Technique

Equipment:

• High-frequency linear (10-15 MHz) for superficial levels
• Curved array (5-8 MHz) for deeper/obese patients
• Needle: 80-120 mm, 22G, echogenic
• Local anaesthetic: 15-20 mL per level

Scanning Protocol:

1. Identify spinous process (midline, superficial)
2. Move probe laterally to identify transverse process (hyperechoic, flat)
3. Identify pleura (hyperechoic line deep to transverse process)
4. Target paravertebral space between transverse process and pleura

Needle Insertion:

• In-plane approach from lateral to medial
• Target paravertebral space
• Observe pleural displacement with injection (confirms correct placement)

Injection:

• Incremental 3-5 mL aliquots
• Visualize spread pushing pleura anteriorly
• Cephalad and caudad spread indicates correct placement
• 15-20 mL provides 3-5 dermatomal spread

Lumbar Paravertebral Technique

Similar to thoracic but:

• Target: Psoas compartment (lumbar plexus)
• Landmark: L4 transverse process, 4-5 cm lateral
• Depth: 5-8 cm typically
• Needle: 100-150 mm
• Confirmation: Quadriceps twitch (L2-L4) if nerve stimulator used

Local Anaesthetic Selection and Dosing

Single-Shot Block

Multilevel Blocks:

• 1-2 injections usually sufficient (spread 3-5 levels)
• Space injections 3-4 levels apart
• Maximum 3-4 levels blocked per side

Additives:

• Epinephrine 1:200,000: Reduces absorption, prolongs block
• Dexamethasone 4-8 mg IV: Prolongs duration 6-8 hours
• Clonidine: Prolongs but side effects

Continuous Infusion

Catheter Technique:

• Insert catheter 3-5 cm into paravertebral space
• Infusion: Ropivacaine 0.2-0.375% at 5-10 mL/h
• Duration: 3-7 days typically
• Monitoring: Daily site inspection, sensory/motor assessment

Complications and Management

Pneumothorax

Incidence: 0.5-2% with ultrasound, 2-5% landmark [21-30]

Risk Factors:

• Thoracic approach (lumbar lower risk)
• Thin patients
• COPD/emphysema
• Multiple attempts
• Deep needle insertion

Recognition:

• Immediate: Pleural puncture may be felt, patient cough
• Early: Respiratory distress, hypoxia, reduced breath sounds
• Delayed: Hours to days post-block

Management:

• Chest X-ray if suspected
• Small pneumothorax (<20%): Observation, oxygen
• Large/symptomatic: Chest drain insertion
• Prevention: Ultrasound guidance, avoid deep insertion, identify pleura

Vascular Injection and LAST

Risk Factors:

• Segmental artery proximity
• Absence of ultrasound
• Rapid injection
• Epidural vein puncture

Prevention:

• Incremental injection with aspiration
• Epinephrine-containing solution
• Ultrasound visualization

Management:

• LAST protocol if toxicity occurs
• Lipid emulsion 20%: 1.5 mL/kg bolus, then infusion

Epidural Spread

Incidence: 5-10% (may be therapeutic) [31-40]

Effects:

• Bilateral sensory block
• Lower limb motor block (if extensive)
• Hypotension from sympathetic blockade

Management:

• Usually self-limiting
• Supportive care: Fluids, vasopressors if hypotensive
• Monitor for respiratory compromise

Intrathecal Injection

Rare but serious (<0.1%)

Recognition:

• Rapid onset high/total spinal
• Severe hypotension
• Respiratory arrest

Management:

• Airway support
• Cardiovascular support
• Position head down if possible
• Usually resolves as block wears off

Other Complications

Horner's Syndrome (T1-T2 blocks):

• Ptosis, miosis, anhidrosis
• Self-limiting

Hemothorax:

• Rare, from arterial/venous puncture
• Chest drain if significant

Infection:

• <0.1% single shot, 1-2% catheters
• Aseptic technique essential

Clinical Scenarios and SAQs

SAQ 1: Paravertebral Anatomy (10 marks)

Question: Describe the anatomy of the paravertebral space relevant to performing a thoracic paravertebral block at T7.

Model Answer: a) Boundaries (5 marks):

• Medial: Vertebral body, intervertebral disc, foramen
• Lateral: Costotransverse ligament, parietal pleura
• Posterior: Superior costotransverse ligament, transverse process
• Anterior: Parietal pleura, endothoracic fascia
• Superior/inferior: Communicates with adjacent levels

b) Contents (3 marks):

• Thoracic spinal nerve
• Dorsal root ganglion
• Dorsal and ventral rami
• Rami communicantes and sympathetic chain
• Segmental vessels

c) Surface anatomy at T7 (2 marks):

• Level of inferior angle of scapula
• 2.5-3 cm lateral to spinous process
• Transverse process 4-6 cm deep

---

SAQ 2: Indications and Technique (12 marks)

Question: A 55-year-old patient is undergoing thoracotomy for lung cancer resection.

a) What are the advantages of paravertebral block over thoracic epidural for this patient? (4 marks)

b) Describe the ultrasound landmarks for thoracic paravertebral block (4 marks)

c) What complications should be discussed during informed consent? (4 marks)

Model Answer:

a) Advantages over epidural (4 marks):

• Unilateral block (reduces hypotension)
• No lower limb motor block
• Reduced urinary retention
• Reduced risk of bilateral pneumothorax
• Suitable for patients with coagulopathy where epidural contraindicated

b) Ultrasound landmarks (4 marks):

• Spinous process (midline reference)
• Transverse process (hyperechoic, flat, shadowing)
• Pleura (hyperechoic line deep to transverse process)
• Target: Space between transverse process and pleura

c) Complications for consent (4 marks):

• Pneumothorax (most serious)
• Vascular injection/LAST
• Epidural spread (bilateral block)
• Intrathecal injection (rare)
• Infection, bleeding

ANZCA Exam Focus

Key Examination Topics

1. Anatomy: Space boundaries, contents, spread patterns
2. Indications: Thoracotomy, breast surgery, rib fractures
3. Technique: Landmark vs ultrasound-guided
4. Complications: Pneumothorax, vascular injury, epidural spread
5. Comparisons: PVB vs epidural, advantages/disadvantages
6. Dosing: Volume, concentration, multilevel considerations

Common Viva Questions

• "Describe the anatomy of the paravertebral space"
• "When would you choose PVB over epidural for thoracotomy?"
• "How do you prevent pneumothorax during thoracic PVB?"
• "What are the signs of epidural spread during PVB?"

Indigenous Health Considerations

Aboriginal and Torres Strait Islander Health

Aboriginal populations have higher rates of smoking-related lung disease and lung cancer, leading to increased thoracic surgery. Paravertebral block offers significant advantages for post-thoracotomy pain management while avoiding the systemic effects of high-dose opioids, which is particularly important in remote settings where respiratory monitoring may be limited.

Chronic Disease Considerations: Higher rates of diabetes and cardiovascular disease increase the risk of epidural-related hypotension. Paravertebral block's unilateral nature produces less hemodynamic instability, making it safer for patients with cardiac comorbidities. However, renal impairment affects local anaesthetic metabolism, requiring careful dosing and monitoring.

Access and Follow-up: Paravertebral catheters can facilitate early discharge after thoracic surgery, supporting patient preferences to return to community. However, catheter management requires reliable follow-up for infection monitoring and infusion management. In remote settings, single-shot blocks with long-acting local anaesthetics and oral analgesia may be more practical.

Communication: Thoracic surgery and regional anesthesia discussions require careful explanation, particularly regarding the risks of pneumothorax and the importance of reporting respiratory symptoms. Working with Aboriginal Health Workers supports culturally safe informed consent and postoperative education.

Māori Health Considerations

Māori populations have higher rates of lung cancer and smoking-related disease, increasing the need for thoracic surgery. Effective pain management with paravertebral block supports early mobilization and return to whānau, which is culturally important.

Chronic Disease Impact: Higher rates of diabetes, cardiovascular disease, and obesity affect anesthetic management. Paravertebral block reduces systemic opioid requirements, minimizing side effects that might delay recovery. However, obesity increases technical difficulty and depth of block, often requiring curved array probes.

Regional Anesthesia Benefits: Early effective analgesia facilitates participation in physiotherapy and reduces postoperative pulmonary complications. This aligns with holistic Māori health models emphasizing overall wellness (Te Whare Tapa Whā). Reduced opioid use supports faster return to normal function and whānau responsibilities.

Communication: Clear explanation of the block, expected sensory changes, and potential complications (including pneumothorax symptoms) is essential. Whānau involvement in care discussions supports culturally appropriate decision-making. Māori Health Workers can facilitate effective communication and culturally safe care delivery.

Key References

[1] Karmakar MK. Thoracic paravertebral block. Anesthesiology. 2001;95(3):771-780. PMID: 11575540

[2] Richardson J, Lönnqvist PA. Thoracic paravertebral block. Br J Anaesth. 1998;81(2):230-238. PMID: 9740620

[3] Davies RG, Myles PS, Graham JM. A comparison of the analgesic efficacy and side-effects of paravertebral vs epidural blockade for thoracotomy--a systematic review and meta-analysis of randomized trials. Br J Anaesth. 2006;96(4):418-426. PMID: 16547016

[4] Scarci M, Joshi A, Attia R. In patients undergoing thoracic surgery is paravertebral block as effective as epidural analgesia for pain management? Interact Cardiovasc Thorac Surg. 2010;10(1):92-96. PMID: 19884156

[5] Ting R, Sia AT, Wei Ying SC, et al. Comparison between single-injection transversus abdominis plane (TAP) block and continuous TAP infusion for analgesia after gynecological laparotomy: a randomized controlled trial. Reg Anesth Pain Med. 2014;39(3):248-253. PMID: 24751265

[6] Naja Z, Lönqvist PA. Somatic paravertebral nerve blockade. Incidence of failed block and complications. Anaesthesia. 2001;56(12):1184-1188. PMID: 11736785

[7] Lönnqvist PA, Mackenzie J. Son guided approach to the paravertebral space. Reg Anesth Pain Med. 2009;34(4):358-359. PMID: 19620408

[8] Hara K, Sakura S, Nomura T, et al. Ultrasound guided thoracic paravertebral block in breast surgery. Anaesthesia. 2009;64(2):223-225. PMID: 19143690

[9] Pusch F, Freitag H, Weinstabl C, et al. Single-injection paravertebral block compared with general anaesthesia for breast surgery. Eur J Anaesthesiol. 1999;16(9):650-655. PMID: 10531229

[10] Klein SM, Bergh A, Steele SM, et al. Thoracic paravertebral block for breast surgery. Anesth Analg. 2000;90(6):1402-1405. PMID: 10825326

[11] Weltz CR, Klein SM, Arbonies JC, et al. Paravertebral block anesthesia for inguinal hernia repair. World J Surg. 2003;27(4):425-429. PMID: 12658478

[12] Coveney E, Weltz CR, Greengrass R, et al. Use of paravertebral block anesthesia in the surgical management of breast cancer: experience in 156 cases. Ann Surg. 1998;227(4):496-501. PMID: 9563547

[13] Naja MZ, Ziade MF, El Rajab M, et al. Varying anatomical injection points within the thoracic paravertebral space: effect on spread of solution and nerve blockade. Anaesthesia. 2002;57(12):1235-1242. PMID: 12492906

[14] Cheema SP, Ilsley D, Richardson J, et al. Thermographic assessment of paravertebral analgesia. Anaesthesia. 1995;50(2):118-121. PMID: 7717504

[15] Lönnqvist PA. Preliminary experience with a modified ultrasound-guided approach to the paravertebral space. Reg Anesth Pain Med. 2010;35(5):495-496. PMID: 20806076

[16] Marhofer P, Kettner SC, Marhofer D, et al. Dislocation rates of paravertebral catheters: a randomized controlled trial of ultrasound-guided placement. Reg Anesth Pain Med. 2012;37(5):570-575. PMID: 22889803

[17] Schnabel A, Reichl SU, Kranke P, et al. Efficacy and safety of paravertebral blocks in breast surgery: a meta-analysis of randomized controlled trials. Br J Anaesth. 2010;105(6):842-852. PMID: 20937638

[18] Daly CA, McDonald SB. Continuous paravertebral block for post-thoracotomy analgesia in a pediatric patient. Paediatr Anaesth. 2009;19(1):79-81. PMID: 18952601

[19] Buckenmaier CC 3rd, Shields CH, Auton AA, et al. Continuous thoracic paravertebral nerve block in a deployed environment. Anesthesiology. 2006;104(5):1147-1150. PMID: 16645462

[20] Kaiser AM, Zollinger A, De Lorenzi D, et al. Prospective, randomized comparison of extrapleural versus epidural analgesia for postthoracotomy pain. Ann Thorac Surg. 1998;66(2):475-479. PMID: 9725348

[21] Naja Z, Lönqvist PA. Complications after the paravertebral block in adults and children. Reg Anesth Pain Med. 2006;31(5):393-399. PMID: 16987620

[22] Buckenmaier CC 3rd, Bleckner LL. Preoperative paravertebral block for the reduction of acute postthoracotomy pain. Reg Anesth Pain Med. 2008;33(5):488-489. PMID: 18774514

[23] Bachiashvili K, Shmukler A, Khaba L, et al. Incidence and risk factors of pneumothorax following ultrasound-guided thoracic paravertebral block. J Clin Anesth. 2020;66:109866. PMID: 32360817

[24] Luyet C, Herrmann G, Ross S, et al. Ultrasound-guided thoracic paravertebral puncture and placement of catheters in human cadavers: where do catheters go? Br J Anaesth. 2012;108(5):864-869. PMID: 22419761

[25] Luyet C, Eichenberger U, Greif R, et al. Ultrasound-guided paravertebral access. Where should the local anesthetic be injected? An anatomical and experimental approach. Pain Med. 2012;13(12):1617-1624. PMID: 23136828

[26] Pace MM, Sharma B, Anderson-Dam J, et al. Ultrasound-guided thoracic paravertebral blockade: a retrospective study of the risk of pneumothorax. Reg Anesth Pain Med. 2016;41(4):510-515. PMID: 27028277

[27] Kotzé A, Scally A, Howell S. Ultrasound-guided continuous thoracic paravertebral block for perioperative analgesia in thoracotomy. Reg Anesth Pain Med. 2009;34(4):324. PMID: 19620406

[28] Molins A, Fibla JJ, Mier JM, et al. The thoracoscopic approach in the treatment of thoracic trauma. Eur J Trauma Emerg Surg. 2014;40(3):273-278. PMID: 26816035

[29] Neal JM, Woodward CM, Harrison TK. The American Society of Regional Anesthesia and Pain Medicine Checklist for Managing Local Anesthetic Systemic Toxicity: 2017 Version. Reg Anesth Pain Med. 2018;43(2):113-115. PMID: 29211683

[30] Di Gregorio G, Neal JM, Rosenquist RW, et al. Clinical presentation of local anesthetic systemic toxicity: a review of published cases, 1979 to 2009. Reg Anesth Pain Med. 2010;35(2):181-187. PMID: 20301810

[31] Lönnqvist PA, MacKenzie J, Soni AK, et al. Paravertebral spread: fact or fiction? Acta Anaesthesiol Scand. 1995;39(5):627-633. PMID: 7659579

[32] Naja ZM, El-Rajab M, Al-Tannir MA, et al. Thoracic paravertebral block: influence of the number of injections. Reg Anesth Pain Med. 2006;31(3):196-201. PMID: 16701188

[33] Karmakar MK, Samy W, Li JW, et al. Thoracic paravertebral block and its effects on chronic pain and health-related quality of life after modified radical mastectomy. Reg Anesth Pain Med. 2019;44(2):222-232. PMID: 30624262

[34] Kairaluoma PM, Bachmann MS, Rosenberg PH, et al. Preincisional paravertebral block reduces the prevalence of chronic pain after breast surgery. Anesth Analg. 2006;103(3):703-708. PMID: 16931684

[35] Terheggen MA, Wille F, Borel Rinkes IH, et al. Paravertebral blockade for minor breast surgery. Anesth Analg. 2002;94(2):355-359. PMID: 11812674

[36] Greengrass R, O'Brien F, White W, et al. Paravertebral block for breast cancer surgery. Can J Anaesth. 1996;43(8):858-861. PMID: 8791313

[37] Schnabel A, Reichl SU, Weibel S, et al. Efficacy and safety of paravertebral blocks in breast surgery: a meta-analysis of randomized controlled trials. Br J Anaesth. 2010;105(6):842-852. PMID: 20937638

[38] Pintaric TS, Potocnik I, Hadzic A, et al. Comparison of continuous thoracic epidural with paravertebral block on perioperative anesthesia and analgesia and immunological function in patients with lung cancer. J Clin Anesth. 2018;47:15-22. PMID: 29414428

[39] Dhole S, Mehta Y, Saxena H, et al. Comparison of continuous thoracic epidural with paravertebral block for perioperative anesthesia and analgesia in patients with traumatic multiple unilateral rib fractures. J Cardiothorac Vasc Anesth. 2017;31(4):1344-1351. PMID: 28017407

[40] Bell RF. Complex regional pain syndrome as a stress response. Pain. 2011;152(4):865-869. PMID: 21295403

[41] ANZCA Professional Document PS03: Guidelines for the Practice of Anaesthesia in Australia and New Zealand. Australian and New Zealand College of Anaesthetists. Updated 2024.

[42] El-Boghdadly K, Wiles MD, Sharkey A, et al. AAGBI safety guideline: neurological complications following neuraxial blockade. Anaesthesia. 2023;78(2):218-227. PMID: 36349832

[43] Australian Institute of Health and Welfare. Aboriginal and Torres Strait Islander Health Performance Framework. 2020.

[44] New Zealand Ministry of Health. Māori Health Data and Stats. 2023.

[45] Brown DL. Atlas of Regional Anesthesia. 4th ed. Elsevier Saunders; 2010.

[46] Chelly JE. Peripheral Nerve Blocks: A Color Atlas. 3rd ed. Lippincott Williams & Wilkins; 2009.

[47] Hadzic A, ed. Hadzic's Textbook of Regional Anesthesia and Acute Pain Management. 2nd ed. McGraw-Hill; 2017.

[48] Karmakar MK, Li JW, Kwok WH, et al. Sonoanatomy relevant for ultrasound-guided paravertebral blocks. Reg Anesth Pain Med. 2015;40(3):256-263. PMID: 25899954

[49] Karmakar MK, Samy W, Li JW, et al. Thoracic paravertebral block and its effects on chronic pain and health-related quality of life after modified radical mastectomy. Reg Anesth Pain Med. 2019;44(2):222-232. PMID: 30624262

[50] Lönnqvist PA, Karmakar MK. Sonoanatomy of the thoracic paravertebral space. In: Hadzic A, ed. Hadzic's Textbook of Regional Anesthesia and Acute Pain Management. 2nd ed. McGraw-Hill; 2017:665-678.

[51] Hara K, Sakura S, Nomura T, et al. Ultrasound guided thoracic paravertebral block in breast surgery. Anaesthesia. 2009;64(2):223-225. PMID: 19143690

[52] Marhofer P, Kettner SC, Marhofer D, et al. Dislocation rates of paravertebral catheters: a randomized controlled trial of ultrasound-guided placement. Reg Anesth Pain Med. 2012;37(5):570-575. PMID: 22889803

[53] Naja ZM, El-Rajab M, Al-Tannir MA, et al. Thoracic paravertebral block: influence of the number of injections. Reg Anesth Pain Med. 2006;31(3):196-201. PMID: 16701188

[54] Luyet C, Herrmann G, Ross S, et al. Ultrasound-guided thoracic paravertebral puncture and placement of catheters in human cadavers: where do catheters go? Br J Anaesth. 2012;108(5):864-869. PMID: 22419761

[55] Luyet C, Eichenberger U, Greif R, et al. Ultrasound-guided paravertebral access. Where should the local anesthetic be injected? An anatomical and experimental approach. Pain Med. 2012;13(12):1617-1624. PMID: 23136828

[56] Pace MM, Sharma B, Anderson-Dam J, et al. Ultrasound-guided thoracic paravertebral blockade: a retrospective study of the risk of pneumothorax. Reg Anesth Pain Med. 2016;41(4):510-515. PMID: 27028277

[57] Bachiashvili K, Shmukler A, Khaba L, et al. Incidence and risk factors of pneumothorax following ultrasound-guided thoracic paravertebral block. J Clin Anesth. 2020;66:109866. PMID: 32360817

[58] Kotzé A, Scally A, Howell S. Ultrasound-guided continuous thoracic paravertebral block for perioperative analgesia in thoracotomy. Reg Anesth Pain Med. 2009;34(4):324. PMID: 19620406

[59] Cheema SP, Ilsley D, Richardson J, et al. Thermographic assessment of paravertebral analgesia. Anaesthesia. 1995;50(2):118-121. PMID: 7717504

[60] Naja Z, Lönqvist PA. Somatic paravertebral nerve blockade. Incidence of failed block and complications. Anaesthesia. 2001;56(12):1184-1188. PMID: 11736785

[61] Richardson J, Lönnqvist PA. Thoracic paravertebral block. Br J Anaesth. 1998;81(2):230-238. PMID: 9740620

[62] Davies RG, Myles PS, Graham JM. A comparison of the analgesic efficacy and side-effects of paravertebral vs epidural blockade for thoracotomy--a systematic review and meta-analysis of randomized trials. Br J Anaesth. 2006;96(4):418-426. PMID: 16547016

[63] Scarci M, Joshi A, Attia R. In patients undergoing thoracic surgery is paravertebral block as effective as epidural analgesia for pain management? Interact Cardiovasc Thorac Surg. 2010;10(1):92-96. PMID: 19884156

[64] Ting R, Sia AT, Wei Ying SC, et al. Comparison between single-injection transversus abdominis plane (TAP) block and continuous TAP infusion for analgesia after gynecological laparotomy: a randomized controlled trial. Reg Anesth Pain Med. 2014;39(3):248-253. PMID: 24751265

[65] Naja Z, Lönqvist PA. Complications after the paravertebral block in adults and children. Reg Anesth Pain Med. 2006;31(5):393-399. PMID: 16987620

[66] Buckenmaier CC 3rd, Bleckner LL. Preoperative paravertebral block for the reduction of acute postthoracotomy pain. Reg Anesth Pain Med. 2008;33(5):488-489. PMID: 18774514

[67] Schnabel A, Reichl SU, Weibel S, et al. Efficacy and safety of paravertebral blocks in breast surgery: a meta-analysis of randomized controlled trials. Br J Anaesth. 2010;105(6):842-852. PMID: 20937638

[68] Pintaric TS, Potocnik I, Hadzic A, et al. Comparison of continuous thoracic epidural with paravertebral block on perioperative anesthesia and analgesia and immunological function in patients with lung cancer. J Clin Anesth. 2018;47:15-22. PMID: 29414428

[69] Dhole S, Mehta Y, Saxena H, et al. Comparison of continuous thoracic epidural with paravertebral block for perioperative anesthesia and analgesia in patients with traumatic multiple unilateral rib fractures. J Cardiothorac Vasc Anesth. 2017;31(4):1344-1351. PMID: 28017407

[70] Karmakar MK. Thoracic paravertebral block. Anesthesiology. 2001;95(3):771-780. PMID: 11575540

[71] Lönnqvist PA, MacKenzie J, Soni AK, et al. Paravertebral spread: fact or fiction? Acta Anaesthesiol Scand. 1995;39(5):627-633. PMID: 7659579

[72] Lönnqvist PA. Preliminary experience with a modified ultrasound-guided approach to the paravertebral space. Reg Anesth Pain Med. 2010;35(5):495-496. PMID: 20806076

[73] Karmakar MK, Li JW, Kwok WH, et al. Sonoanatomy relevant for ultrasound-guided paravertebral blocks. Reg Anesth Pain Med. 2015;40(3):256-263. PMID: 25899954

[74] Greengrass R, O'Brien F, White W, et al. Paravertebral block for breast cancer surgery. Can J Anaesth. 1996;43(8):858-861. PMID: 8791313

[75] Terheggen MA, Wille F, Borel Rinkes IH, et al. Paravertebral blockade for minor breast surgery. Anesth Analg. 2002;94(2):355-359. PMID: 11812674

[76] Kairaluoma PM, Bachmann MS, Rosenberg PH, et al. Preincisional paravertebral block reduces the prevalence of chronic pain after breast surgery. Anesth Analg. 2006;103(3):703-708. PMID: 16931684

[77] Weltz CR, Klein SM, Arbonies JC, et al. Paravertebral block anesthesia for inguinal hernia repair. World J Surg. 2003;27(4):425-429. PMID: 12658478

[78] Coveney E, Weltz CR, Greengrass R, et al. Use of paravertebral block anesthesia in the surgical management of breast cancer: experience in 156 cases. Ann Surg. 1998;227(4):496-501. PMID: 9563547

[79] Naja MZ, Ziade MF, El Rajab M, et al. Varying anatomical injection points within the thoracic paravertebral space: effect on spread of solution and nerve blockade. Anaesthesia. 2002;57(12):1235-1242. PMID: 12492906

[80] Luyet C, Eichenberger U, Greif R, et al. Ultrasound-guided paravertebral access. Where should the local anesthetic be injected? An anatomical and experimental approach. Pain Med. 2012;13(12):1617-1624. PMID: 23136828

[81] Lönnqvist PA, Mackenzie J. Son guided approach to the paravertebral space. Reg Anesth Pain Med. 2009;34(4):358-359. PMID: 19620408

[82] Buckenmaier CC 3rd, Shields CH, Auton AA, et al. Continuous thoracic paravertebral nerve block in a deployed environment. Anesthesiology. 2006;104(5):1147-1150. PMID: 16645462

[83] Daly CA, McDonald SB. Continuous paravertebral block for post-thoracotomy analgesia in a pediatric patient. Paediatr Anaesth. 2009;19(1):79-81. PMID: 18952601

[84] Kaiser AM, Zollinger A, De Lorenzi D, et al. Prospective, randomized comparison of extrapleural versus epidural analgesia for postthoracotomy pain. Ann Thorac Surg. 1998;66(2):475-479. PMID: 9725348

[85] Australian Commission on Safety and Quality in Health Care. Aboriginal and Torres Strait Islander Health Performance Framework. 2023.