what is COPD?
- preventable and treatable disease characterised persistent, progressive airflow limitation (not fully reversible)
- enhanced chronic inflammatory response in the lungs to noxious gases/particles
what happens with large airways inflammation?
airways narrowing due to chronic irritation of the bronchi causing inflammation and changes to the mucociliary escalator often results in a chronic cough
what happens with the small airways?
airways narrowing due to bronchoconstriction and inflammation; duration and severity are risk factors for development or airway remodelling and COPD
what happens with emphysema?
airways collapse due to destruction of alveolar walls - may lead to bullae
what happens to the airways with COPD?
- chronic inflammation
- increased number of goblet cells
- mucus hyperplasia
- fibrosis
- narrowing and reduction in the number of small airways
- airway collapse due to alveolar wall destruction in emphysema
what are the symptoms for chronic bronchitis (large airways)?
- chronic productive cough for 3 months in 2 successive years
- exclude other causes of chronic cough
what are the symptoms of emphysema (alveolar)?
- abnormal and permanent enlargement of the airspace due to destruction of the alveolar airspace walls
- effects gas exchange
what are the symptoms of small airways disease?
wheeze
what are the risk factors of COPD?
- cigarette smoke
- occupational dust and chemicals
- environmental tobacco smoke (ETS)
- indoor and outdoor air pollution
- genes
- infections
- socio-economic status
- ageing population
what smoking history do you need to take?
- age started
- calculate pack-year history
- times stopped and why failed quit attempt
- recreational drugs smoked (or other substances)
how do you diagnose COPD?
symptoms + risk factors + spirometry
what is the impact of grade 1 COPD?
not troubled by breathlessness except on vigorous exertion
what is the impact of grade 2 COPD?
short of breath when hurrying or walking up inclines
what is the impact of grade 3 COPD?
walks slower than contemporaries because of breathlessness or has to stop for breath when walking at own pace
what is the impact of grade 4 COPD?
stops for breath after walking about 100m or stops after a few minutes walking on the level
what is the impact of grade 5 COPD?
too breathless to leave the house or breathless on dressing or undressing
what are the physical signs of COPD?
- barrel shaped chest
- hyperresonant percussion
- accessory muscles
- prolonged expiration
- pursed-lip breathing
- tripod position
- low BMI
- nicotine staining
what are the physiological effects of COPD?
- increased work of breathing
- reduced exercise tolerance
- impaired gas exchange: hypoxia, hypercapnia, raised pulmonary artery pressure, RV dilatation, cor pulmonale
- loss of fat-free mass
how do you manage chronic COPD?
- stop smoking
- if symptomatic LABA/LAMA combined inhaler
- lots of inhalers
- flu vaccination
- educate and empower
- treat exacerbations
- pulmonary rehabilitation
- think about the whole patient (bones, nutrition, mental health)
- LTOT
what happens with pulmonary rehabilitation?
- 2x supervised sessions for 6 weeks
- supervised exercise
- education
- psychosocial support/group work
what are the other possible treatments for COPD?
- theophylline (oral phosphodiesterase inhibitor)
- azithromycin 3x a week (anti-inflammatory antibiotic prophylaxi)
- lung volume reduction surgery
- lung transplantation
what is acute exacerbation?
acute deterioration in symptoms requiring additional therapy
- mild (SABA)
- moderate (SABA +/- steroids +/- antibiotics)
- severe (hospital admission) or ED attendance
what happens with severe exacerbation of COPD?
ED attendance due to progressive dyspnoea/hypoxia or signs of infection or signs of right heart failure
- antibiotics in signs of infection
- oral steroids
- target saturation 88-92%
- nebulisers
- consider diruetics
- nicotine replacement therapy/refer for smoking cessation
why do you use non-invasive ventilation for COPD?
decompensated hypercapnic respiratory failure despite controlled oxygen and nebuliser treatments
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mechanisms of breathing, pressures & work29
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measuring lung function17
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gas exchange & gas transport21
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arterial blood gas32
-
respiratory failure33
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oxygen therapy & sleep apnoea44
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asthma23
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respiratory infection42
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imaging the thorax19
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COPD27
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clinical consequences of respiratory infection21
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tuberculosis25
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HIV & respiratory infections11
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interstitial lung diseases30
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pleural & chest wall diseases30
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respiratory pharmacology49
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cough & breathlessness10
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lung cancer12
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occupational lung disease25
