Obstructive Airway Diseases and Asthma — WACS Viva & Clinical Scenarios (Respiratory Medicine)

Exam-style obstructive airway diseases and asthma viva scenarios with examiner probes and model answers for Internal Medicine candidates.

Scenarios covered

• SCENARIO 1: A 26-year-old woman with a history of atopic asthma presents to the emergency centre with severe acute breathlessness, orthopnoea, and inability to complete short phrases in one breath. Vital signs reveal a pulse rate of 132 beats per minute, respiratory rate of 38 breaths per minute, blood pressure of 115/75 mmHg, and SpO₂ of 88 percent on room air. Chest auscultation reveals marked hyperinflation with quiet breath sounds and faint expiratory wheeze bilaterally. Arterial blood gas on room air demonstrates: pH 7.39, PaCO₂ 42 mmHg (5.6 kPa), PaO₂ 56 mmHg (7.5 kPa), and HCO₃⁻ 24 mmol/L. Outline
• SCENARIO 2: A 64-year-old non-smoking woman living in a peri-urban community presents with a 4-year history of progressive exertional dyspnoea, chronic cough, and early morning mucoid sputum production. She gives a 35-year history of daily domestic cooking with firewood and charcoal in poorly ventilated spaces. Physical examination reveals an increased anteroposterior chest diameter and diminished breath sounds. Post-bronchodilator spirometry shows FEV₁/FVC 0.56 and FEV₁ 48 percent of predicted with no significant reversibility. Formulate a comprehensive evaluation and management plan, including the patho
• SCENARIO 3: A 42-year-old man who successfully completed category 1 anti-tuberculosis therapy six years ago presents with recurrent lower respiratory tract infections, daily expectoration of copious foul-smelling purulent sputum, and three episodes of frank haemoptysis over the preceding fortnight. High-resolution computed tomography (HRCT) confirms extensive bilateral cylindrical and cystic bronchiectasis. Discuss the microbiological investigation protocol, long-term airway clearance and pharmacological strategies, and the systematic clinical approach to the management of massive haemoptysis in this pati
• SCENARIO 4: A 70-year-old male with established severe COPD is admitted with acute deterioration in dyspnoea, increased sputum volume, and purulence. Arterial blood gas analysis on 28 percent Venturi mask oxygen shows: pH 7.27, PaCO₂ 62 mmHg (8.3 kPa), PaO₂ 58 mmHg (7.7 kPa), and HCO₃⁻ 30 mmol/L. Describe the immediate medical management, the precise indications and initial machine parameter settings for bi-level non-invasive positive pressure ventilation (NIV), your schedule for arterial blood gas reassessment, and the parameters defining non-invasive ventilation failure.
• SCENARIO 5: At an objective structured clinical examination station, demonstrate the proper technique for performing and interpreting diagnostic spirometry in a patient undergoing evaluation for airflow limitation. Explain the physiological criteria defining reversibility, detail the correct technique for administering aerosolised medication using a metered-dose inhaler with a spacer, and counsel the patient on maintaining a peak expiratory flow diary.