COPD Viva

Long Case Viva Defence

Candidate's opening statement (model answer)

"Mr Hayes is a 70-year-old retired boilermaker and 50 pack-year smoker who presents with a 4-day history of worsening dyspnoea, purulent sputum, and drowsiness. He has severe COPD (GOLD 3, Group E), cor pulmonale, osteoporosis, and depression. [1]

His background medications are tiotropium, salmeterol/fluticasone, salbutamol PRN, frusemide, sertraline, and alendronate. [1]

On arrival he was cyanosed with a respiratory rate of 28, SpO2 82% on room air. His ABG on 28% oxygen showed pH 7.27, PaCO2 75, PaO2 56 — acute-on-chronic hypercapnic respiratory failure. His CXR showed hyperinflation only. [1]

His main problems are:

1. Acute exacerbation of COPD with acute hypercapnic respiratory failure requiring NIV
2. Severe COPD (GOLD 3, Group E) with a frequent-exacerbator phenotype
3. Cor pulmonale with pulmonary hypertension
4. Possible inappropriate ICS use — his blood eosinophils are low, predicting poor response and pneumonia risk
5. Osteoporosis and depression
6. Ongoing tobacco dependence" [1]

Examiner probing questions and model answers

Q1: "Walk me through your immediate management of this patient." [1]

"My priorities are controlled oxygen, bronchodilation, corticosteroids, antibiotics, and non-invasive ventilation. First, I confirm he is on controlled oxygen via a 28% Venturi mask targeting SpO2 88-92% — I would never give high-flow oxygen to a CO2-retaining COPD patient because excess oxygen worsens hypercapnia through the Haldane effect and increased V/Q shunt. Second, I start nebulised salbutamol 5 mg and ipratropium 500 mcg, repeating every 4-6 hours. Third, prednisone 40 mg orally daily for 5 days — the REDUCE trial showed 5 days is non-inferior to 14. Fourth, amoxicillin-clavulanate 875/125 mg BID for 5 days, because he has an Anthonisen Type 1 exacerbation with purulent sputum and a raised CRP. Fifth — and most importantly — I commence non-invasive ventilation with BiPAP, because his pH is 7.27 and PaCO2 is 75 after standard therapy, which is the established indication for NIV. Plant et al. showed NIV halves intubation and mortality in this setting. I would set IPAP at 10-12, EPAP at 4-5, and titrate FiO2 to keep SpO2 88-92%, then recheck the ABG at 1-2 hours." [1]

Q2: "Why did you choose BiPAP over intubation?" [1]

"NIV is first-line for acute hypercapnic respiratory failure in COPD because it avoids the complications of invasive ventilation — ventilator-associated pneumonia, sedation, delirium — and has proven mortality benefit. The Plant trial randomised patients exactly like him to standard therapy versus early ward-based NIV, and NIV reduced intubation from 27% to 15% and in-hospital mortality from 20% to 10%. I would reserve intubation for NIV failure — persisting or worsening acidosis (pH less than 7.25) despite optimised NIV over 1-4 hours, deterioration in consciousness, respiratory arrest, or haemodynamic instability. He is cooperative and rousable, has no contraindications, so NIV is appropriate. I would escalate to ICU if he fails to improve." [1]

Q3: "He is on salmeterol/fluticasone and his eosinophils are 0.08. Would you continue the inhaled steroid?" [1]

"His blood eosinophils are low, which predicts a poor response to inhaled corticosteroids and a real risk of pneumonia. ICS is not first-line in COPD — the cornerstone is bronchodilation. In an ideal world, once he has recovered from this acute episode, I would trial withdrawal of the fluticasone component and switch him to a LAMA/LABA dual bronchodilator combination, keeping him on tiotropium plus a LABA. I would withdraw the ICS gradually and monitor for exacerbation frequency. I would only re-introduce ICS — as triple therapy — if his exacerbations increase, especially if his eosinophils rise. The IMPACT trial supports triple therapy for frequent exacerbators, but it is not for every patient, and his low eosinophils put him in the group most likely to suffer pneumonia without deriving benefit." [1]

Q4: "What is the role of roflumilast in this patient?" [1]

"Roflumilast is an oral phosphodiesterase-4 inhibitor indicated for severe COPD — GOLD 3 or 4 — with a chronic bronchitis phenotype and a history of frequent exacerbations. He fits those criteria. It is added ON TOP of maximal inhaled therapy, not instead of it. The Calverley trials showed it reduces moderate-to-severe exacerbations in this specific group. Its main adverse effects are nausea, diarrhoea, and weight loss — relevant given his low BMI — so I would counsel him and monitor. It is a second-line add-on if his exacerbations persist despite optimised inhaled therapy." [1]

Q5: "How would you manage his cor pulmonale?" [1]

"Cor pulmonale is right heart failure secondary to a pulmonary cause — here, pulmonary hypertension from chronic hypoxic vasoconstriction in COPD. The primary treatment is the underlying disease: oxygen therapy to reverse chronic hypoxaemia, which is what drives the pulmonary vasoconstriction. Once he is stable, I would assess him for long-term oxygen therapy — if his PaO2 is less than 55, or 55-59 with evidence of end-organ effects such as the cor pulmonale he already has, he qualifies for LTOT at least 15 hours per day. For the right heart failure itself, diuretics (he is already on frusemide) relieve congestion, but I would monitor electrolytes and renal function. I would not routinely use pulmonary vasodilators such as sildenafil or bosentan for COPD-related pulmonary hypertension unless a pulmonary hypertension specialist confirms it is disproportionate to the lung disease — the evidence is weaker than for Group 1 pulmonary arterial hypertension." [1]

Q6: "What is his prognosis and how would you discuss it?" [1]

"He has severe COPD with a frequent-exacerbation phenotype, cor pulmonale, and now a hospitalising exacerbation with respiratory failure. I would calculate his BODE index to give a structured estimate — it is a better predictor of mortality than FEV1 alone because it captures the systemic burden: BMI, obstruction, dyspnoea, and exercise capacity. A BODE score of 7 or above carries an approximate 4-year mortality of 80%. I would discuss prognosis honestly but constructively — emphasising that smoking cessation and long-term oxygen (if he qualifies) are the two interventions that improve survival, that pulmonary rehabilitation improves quality of life and reduces readmission, and that advance care planning is appropriate. I would frame the conversation around maximising the quality of his remaining life, preventing admissions, and agreeing on a ceiling of treatment — for example, whether he would want invasive ventilation or ICU in a future exacerbation." [1]

Short Case Discussion

Scenario: "Examine this patient's respiratory system"

Candidate presentation (model): [1]

"I examined Mr Jones's respiratory system. He is a thin, cachectic man who is breathless at rest, using accessory muscles and pursed-lip breathing, sitting forward in a tripod position. There is central cyanosis. He is not clubbed. There is a fine tremor. The respiratory rate is 24 per minute. [1]

The chest is barrel-shaped with an increased anteroposterior diameter. Cricosternal distance is reduced. Chest expansion is diminished and symmetrical at 3 cm. The percussion note is hyper-resonant throughout. On auscultation, breath sounds are globally reduced with a prolonged expiratory phase and widespread expiratory polyphonic wheeze. [1]

The JVP is elevated 4 cm with a prominent V wave. There is a right ventricular heave at the left sternal edge. The pulmonary component of the second heart sound is loud. There is a pansystolic murmur at the lower left sternal edge that is louder on inspiration. There is pitting oedema to the mid-shin bilaterally. [1]

In summary, these findings are consistent with severe chronic obstructive pulmonary disease with hyperinflation and cor pulmonale secondary to pulmonary hypertension." [1]

Examiner: "Why is he not clubbed?" [1]

"Clubbing is not a feature of uncomplicated COPD. If I found clubbing in a patient who otherwise looked like COPD, I would actively seek an alternative or coexisting diagnosis — lung cancer is the commonest cause in a smoker, followed by bronchiectasis and idiopathic pulmonary fibrosis. The absence of clubbing here is therefore consistent with COPD alone." [1]

Examiner: "Explain the loud P2." [1]

"The pulmonary component of the second heart sound is produced by closure of the pulmonary valve. It becomes loud when pulmonary artery pressure is elevated — the valve closes more forcefully against high pressure. In this patient, chronic hypoxic pulmonary vasoconstriction from COPD has caused pulmonary hypertension, producing the loud P2. Combined with the right ventricular heave, elevated JVP with a prominent V wave of tricuspid regurgitation, and peripheral oedema, this is cor pulmonale — right heart failure due to a pulmonary cause." [1]

Examiner: "Why does he use pursed-lip breathing?" [1]

"Pursed-lip breathing is a learned compensatory behaviour. By exhaling against partially closed lips, the patient creates positive pressure in the airways during expiration. This splints the small airways open — which in COPD tend to collapse prematurely due to loss of elastic recoil from emphysema — reducing gas trapping and dynamic hyperinflation. It allows more complete emptying of the lungs before the next breath, lowering the work of breathing. It is a sign of advanced obstructive disease and reflects the patient's adaptive effort to overcome the mechanical disadvantage of hyperinflation." [1]