Thoracic and Abdominal Wall Anatomy and Fascial Plane Blocks — WACS Viva & Clinical Scenarios (Anatomy, Applied Anatomy and Regional Anaesthesia)

Exam-style thoracic and abdominal wall anatomy and fascial plane blocks viva scenarios with examiner probes and model answers for ANAESTHESIA candidates.

Scenarios covered

• SCENARIO 1: A 52-year-old female with locally advanced carcinoma of the right breast is scheduled for modified radical mastectomy with complete axillary lymph node dissection. Describe the detailed anatomy of the chest wall and axilla, the nerve supply involved (lateral/medial pectoral, intercostobrachial, long thoracic, thoracodorsal, lateral cutaneous branches of intercostal nerves), and your step-by-step ultrasound-guided technique for combined PECS I and PECS II (or modified PECS) blocks.
• SCENARIO 2: A 64-year-old male is admitted with severe blunt chest trauma, resulting in fractures of the right 5th to 9th ribs, severe pleuritic pain, and impending respiratory failure (SpO₂ 88% on room air). Thoracic epidural is deemed high risk. Detail the anatomy of the erector spinae fascial plane, the proposed mechanism of local anaesthetic spread to the ventral and dorsal rami, and your protocol for an ultrasound-guided continuous ESP block.
• SCENARIO 3: A 40-year-old female undergoes an elective open cholecystectomy via a right subcostal (Kocher) incision. You plan a subcostal transversus abdominis plane (TAP) block. Detail the muscular and fascial layers of the anterolateral abdominal wall, the path of the T6-T9 thoracoabdominal nerves, and the anatomical differences between subcostal, lateral, and posterior TAP approaches.
• SCENARIO 4: A 68-year-old male with a history of bilateral open inguinal hernia repair and severe chronic obstructive pulmonary disease undergoes an open radical nephrectomy through a flank incision. Describe the anatomy of the thoracolumbar fascia and the quadratus lumborum muscle. Compare the anatomical spread, target nerves, and clinical efficacy of Quadratus Lumborum Type 1 (lateral), Type 2 (posterior), and Type 3 (transmuscular/anterior) blocks.
• SCENARIO 5: A 7-year-old boy presents for elective repair of an umbilical hernia. You perform a bilateral landmark-based rectus sheath block under general anaesthesia. During injection on the left side, you feel a sudden loss of resistance followed by abdominal distension and tachycardia. What anatomical structures have potentially been breached, what are the potential immediate visceral or vascular complications, and how do you manage this emergency?