COPD (RESP) Flashcards
Define chronic obstructive pulmonary disease.
Heterogeneous progressive lung disease characterised by chronic respiratory symptoms and airflow limitation that is not fully reversible
What does COPD encompass? (3)
- chronic bronchitis - chronic narrowing of airways defined clinically as a productive cough on most days for at least 3 months per year for 2 consecutive years
- emphysema - permanent destructive enlargement of air spaces distal to the terminal bronchioles
- bronchiolitis (small airways disease)
Define chronic bronchitis (COPD).
Chronic narrowing of airways defined clinically as a productive cough on most days for at least 3 months per year for 2 consecutive years
(Exposure to irritants –> hypertrophy and hyperplasia + increased mucus production –> obstruction)
Define emphysema (COPD).
Permanent destructive enlargement of air spaces distal to the terminal bronchioles
(Inflammatory reaction to irritants –> enzymes break down collagen and elastin –> alveoli enlarge and lose recoil elasticity that keeps them open)
What is the bronchial and alveolar damage in COPD caused by?
Environmental toxins (cigarette smoke, dust, NO2) –> activates innate and adaptive immune responses to long term exposure to noxious particles and gases
Describe compliance and resistance of the lungs in COPD.
- increased resistance to airflow in small conducting airways
- increased compliance of lungs
- progressive airflow obstruction
Describe the epidemiology of COPD. (3)
- M>F
- age >65
- smokers
What are the main causes of COPD? (3)
- smoking - most common
- exposure to air pollution
- alpha-1-antitrypsin deficiency (in younger non-smoker patients)
How can alpha-1-antitrypsin deficiency cause COPD?
- inhibited action of neutrophil elastase –> emphysema
- may be accompanied by symptoms of cirrhosis
What condition, other than COPD, is alpha-1-antitrypsin deficiency a risk factor for?
Hepatocellular carcinoma
What management can be done in late stage alpha-1-antitrypsin deficiency?
Lung volume reduction surgery
What are some signs and symptoms of COPD?
- progressive SOB
- wheeze
- chronic cough
- productive, white/clear sputum (yellow = exacerbation/infection)
- sputum production
- reduced exercise tolerance
- dyspnoea and tachypnoea
- cyanosis
- low oxygen sats <92%
- late stage - raised JVP, peripheral oedema
What are some clinical findings on inspection of a COPD patient? (6)
- respiratory distress
- use of accessory muscles (tripod position)
- pursed lip breathing
- barrel-shaped, over-inflated chest
- decreased cricosternal distance
- cyanosis
What are some clinical findings on palpation of a COPD patient?
Reduced chest expansion bilaterally
What are some clinical findings on percussion of a COPD patient? (2)
- hyper-resonant chest
- loss of liver and cardiac dullness
What are some clinical findings on auscultation of a COPD patient? (6)
- distant (quiet) breath sounds
- prolonged expiration
- wheeze
- rhonchi - rattling, continuous and low-pitched breath sounds (like snoring) due to secretions/obstructions
- crepitations
- coarse crackles
What are some signs of CO2 retention in COPD? (3)
- bounding pulse
- warm peripheries
- asterixis (hand flap)
What are some signs of late stage COPD (Cor Pulmonale)? (3)
- right ventricular haeve
- raised JVP
- ankle oedema
What are some non-modifiable risk factors for COPD? (4)
- male sex
- advanced age
- white ancestry
- genetic factors / developmentally abnormal lung
What are some modifiable risk factors for COPD? (4)
- smoking - makes cilia short and less mobile
- occupational exposure (dust, chemicals, vapours, fumes, gases)
- environmental (tobacco smoke, air pollution, indoor solid fuel burning)
- Fx or PMHx of chronic lung disease
What are the gold standard investigations for COPD?
Spirometry and pulmonary function tests
What are the first-line investigations for COPD?
- spirometry
- standardised symptoms score
- pulse oximetry
- ABG
- CXR
- FBC
What does (post-bronchodilator) spirometry + pulmonary function tests show for COPD?
- FEV1/FVC ratio <0.7
- no bronchodilator reversibility (unlike asthma)
- significantly reduced FEV1 (<80% predicted), slightly reduced/normal FVC
- TLC normal/high
How can COPD be classified by severity based on FEV1?
(FEV1/FVC<0.7 for all)
- GOLD 1 (mild): FEV1>80% predicted + symptoms
- GOLD 2 (moderate): 50%<FEV1<79% predicted
- GOLD 3 (severe): 30%<FEV1<49% predicted
- GOLD 4 (very severe): FEV1<30% predicted