COPD
COPD, TB and PCP cause secondary pneumothorax: a pneumothorax is more dangerous in lung disease.
Treatment at a glance
- Stop smoking
- Short-acting bronchodilator as needed
- Long-acting antimuscarinic (tiotropium) ± long-acting beta-agonist
What our notes say
- COPD, TB and PCP cause secondary pneumothorax: a pneumothorax is more dangerous in lung disease. (Pneumothorax)
- Consider if the patient is systemically unwell, very frail, has comorbidity (COPD, heart failure), or pertussis is suspected (macrolide). (Bronchitis (Acute and Chronic))
- Smoking cessation slows the decline in lung function and is the main intervention that alters the course of COPD. (Respiratory Medicine Question Bank: 15 Clinical MCQs)
- | Secondary spontaneous | Underlying lung disease: COPD (commonest), TB, PCP (HIV), cystic fibrosis, asthma, lung cancer, ILD, Marfan syndrome, catamenial (menstrual) | (Pneumothorax)
- Differential: COPD, heart failure ("cardiac asthma"), GORD, vocal cord dysfunction, bronchiectasis, foreign body, PE. (Asthma)
- Spirometry (post-bronchodilator FEV1/FVC below 0.7 = COPD); chest X-ray (increased bronchovascular markings, to exclude other causes); sputum culture in exacerbations; FBC (polycythaemia), ABG. (Bronchitis (Acute and Chronic))
Study material on COPD
- Chronic Obstructive Pulmonary Disease (COPD)
- Examination of Respiratory system
- High-Yield Clinical Exam Notes: Cranial Nerves, Respiratory, Cardio
- Bronchitis (Acute and Chronic)
- Internal Medicine Respiratory CAT 1: 30 MCQs and 5 short answer questions
- Lung Pathology — Must-Know
- Cranial Nerves, Eye Exam & Vital Signs: MBChB Clinical Revision
- Occupational Lung Disease
- Respiratory Medicine Question Bank: 15 Clinical MCQs
- Chemical Pathology MCQs: Clinical Chemistry, Endocrine & Renal
- ACID-BASE DISORDERS - CLINICAL CASE MCQs
- Chemical Pathology MCQs
- Weekly Pathology Exam - June 19, 2026 (Section A: MCQs)
Practice questions on COPD
A 70-year-old man with severe COPD has increasing drowsiness. ABG shows pH 7.28, PaO2 55 mmHg, PaCO2 72 mmHg, and HCO3 32 mEq/L. What is the most likely type of respiratory failure?
- Type I (hypoxemic)
- Type II (hypercapnic)
- Type III (perfusion defect)
- Type IV (pump failure)
Answer: B. This ABG demonstrates respiratory acidosis (pH 7.28) with significant hypercapnia (PaCO2 72 mmHg) and hypoxemia (PaO2 55 mmHg). This is characteristic of Type II respiratory failure, often seen in severe COPD due to alveolar hypoventilation.
A 70-year-old man with severe COPD has increasing drowsiness. ABG shows pH 7.28, PaO2 55 mmHg, PaCO2 72 mmHg, and HCO3 32 mEq/L. Most likely type of respiratory failure?
- Type 2 respiratory failure (hypercapnic)
- Type 1 respiratory failure (hypoxemic)
- Combined type 1 and 2 respiratory failure
- Cardiogenic pulmonary edema
Answer: A. The ABG shows significant hypoxemia (PaO2 55 mmHg) and hypercapnia (PaCO2 72 mmHg), with a compensated metabolic alkalosis (HCO3 32 mEq/L, indicating chronic retention of CO2). This pattern, especially with drowsiness, signifies Type 2 (hypercapnic) respiratory failure, often superimposed on underlying hypoxemia in severe COPD.
A 70-year-old man with severe COPD has increasing drowsiness. ABG shows pH 7.28, PaO2 55 mmHg, PaCO2 72 mmHg, and HCO3 32 mEq/L. Most likely type of respiratory failure?
- Type 1 (hypoxemic)
- Type 2 (hypercapnic)
- Type 3 (peroperative)
- Type 4 (ischemic)
Answer: B. The ABG demonstrates significant hypoxemia (PaO2 55 mmHg) and hypercapnia (PaCO2 72 mmHg) with a resultant respiratory acidosis (pH 7.28). This combination, especially with the elevated PaCO2 and decreased pH, indicates Type 2 (hypercapnic) respiratory failure, common in severe COPD exacerbations.
A 70-year-old man with severe COPD has increasing drowsiness. ABG shows pH 7.28, PaO2 55 mmHg, PaCO2 72 mmHg, and HCO3 32 mEq/L. What is the most likely type of respiratory failure?
- Type I (Hypoxemic)
- Type II (Hypercapnic)
- Type III (Perfusion defect)
- Type IV (Pump failure)
Answer: B. This ABG shows both hypoxemia (PaO2 55 mmHg) and hypercapnia (PaCO2 72 mmHg) with a compensated metabolic alkalosis (HCO3 32 mEq/L). While hypercapnia is present, the severe hypoxemia is the most life-threatening abnormality driving the clinical picture and leading to drowsiness. This combination defines Type II respiratory failure, which can also have hypoxemic components in severe cases of COPD.
A 70-year-old man with severe COPD has increasing drowsiness. ABG shows pH 7.28, PaO2 55 mmHg, PaCO2 72 mmHg, and HCO3 32 mEq/L. Most likely type of respiratory failure?
- Type 2 (hypercapnic)
- Type 1 (hypoxemic)
- Mixed Type 1 and Type 2
- Cardiogenic shock
Answer: A. This ABG demonstrates severe hypercapnia (PaCO2 72 mmHg) with a corresponding respiratory acidosis (pH 7.28). While hypoxemia is also present (PaO2 55 mmHg), the primary driver of the patient's drowsiness and acidosis is the elevated CO2, indicative of Type 2 respiratory failure.
A 70-year-old man with severe COPD has increasing drowsiness. ABG shows pH 7.28, PaO2 55 mmHg, PaCO2 72 mmHg, and HCO3 32 mEq/L. Most likely type of respiratory failure?
- Type I (hypoxemic)
- Type II (hypercapnic)
- Type III (perfusion defect)
- Type IV (shock)
Answer: B. The ABG shows both hypoxemia (PaO2 55 mmHg) and hypercapnia (PaCO2 72 mmHg) with respiratory acidosis (pH 7.28). However, the defining feature for Type II respiratory failure is the elevated PaCO2 leading to respiratory acidosis. While hypoxemia is present, it is a consequence of the impaired ventilation. The presence of significant hypercapnia and acidosis indicates Type II (hypercapnic) respiratory failure. The ele