COPD Flashcards
Define COPD
Chronic progressive irreversible lung disorder characterised by airflow obstruction, chronic bronchitis and emphysema
Chronic Bronchitis: Chronic cough and sputum production on most days for at least 3 months per year over 2 consecutive years
Emphysema: permanent destructive enlargement of air spaces distal to the terminal bronchioles
Aetiology of COPD
Bronchial and alveolar damage due to environmental toxins i.e. smoking
May be caused by alpha-1 antitrypsin deficiency (<1%)
May overlap and co-present with asthma
Aetiology of chronic bronchitis and emphysema
Bronchitis: narrowed airways due to inflammation and mucosal oedema, hypersecretion and squamous metaplasia
Emphysema: destruction and enlargement of alveoli -> loss of elastic traction that keeps them open -> collapse -> bullae formation
Risk factors for COPD
Cigarette smoking, >65, genetic factors, exposure to air pollution, occupation, Male, RA
Epidemiology of COPD
Common in elder people >65
Global prevalence 17.5% M and 9.3% F
Deaths from COPD increasing
Prevalence in never-smokers is 12.2%
Symptoms of COPD
Cough (productive, continuous, chronic) SOB Fatigue Wheeze Weight or muscle loss Headache Reduced exercise tolerance
Signs of COPD on exam
Tar staining Hyperexpanded chest Reduced expansion Asterixis Tachypnoea/resp. distress Tripod position, use of accessory muscles, pursed lip breathing
Reduced breath sounds
Hyperresonance
Wheeze
Coarse crackles
Signs of RHF (Cor Pulmonale)
Investigations for COPD
Spirometry and PFTs - FEV1/FVC ratio <0.7
Modified British Medical Research Council questionnaire
CXR - hyperexpanded chest, hyperlucent, flattened diaphragm
Bloods - assess the severity
ABG - PaCO2 >50, PaO2 <60
ECG and echo - Assess for cor pulmonale (R ventricular hypertrophy, arrhythmias, ischaemia)
Sputum and blood cultures
Alpha-1 antitrypsin levels
PEFR - rule out asthma
CT chest - hyperinflammation, bullae formation
How FEV1/FVC ratio correlates to severity
Mild: >80% predicted
Moderate: 50-80% predicted
Severe: 30-50% predicted
Very severe: <30% predicted
Features of an acute exacerbation of COPD
Worsening breathlessness with increased sputum volume and purulence Cough Wheeze Fever URTI in past 5 days
Admission criteria for COPD
Severe breathlessness
Inability to cope at home
Rapid onset of symptoms
Acute confusion or impaired consciousness
Cyanosis
SpO2 <90
Worsening peripheral oedema or new arrhythmia
Management for an acute exacerbation
- ABCDE
- 24% oxygen through venturi mask
- Salbutamol nebs 5mg AND ipratropium nebs 0.5mg
- Oral prednisolone 30mg
- Severe - ABx e.g. amoxicillin, co-amoxiclav
- NO response -> theophylline IV
Management for an acute exacerbation with decompensated T2RF
- ABCDE
- Refer to ITU
- Aim oxygen 98%
- salbutamol nebs 5mg and ipratropium nebs 0.5mg
- oral prednisolone 30mg
- CPAP or BiPAP
Conservative management for chronic COPD
STOP smoking
influenza and pneumococcal vaccines
Pulmonary rehab (aerobic exercise, strength training)
Breathing and chest physio
± mucolytics e.g. carbocysteine
± long-term oxygen therapy (LTOT) if PaO2 <7.3 despite maximal treatment | PaO2 7.3-8.0 + pulmonary HTN, peripheral oedema, polycythaemia, nocturnal hypoxia | terminally ill
± home news
± BiPAP
Medical management for chronic COPD
- SABA or SAMA
- No asthmatic features - LABA or LAMA
- Asthmatic features - LABA + ICS
- LABA + LAMA + ICS
Long term oxygen, lung volume reduction surgery
Asthmatic/steroid-responsive: Any previous diagnosis of asthma or atopy Higher eosinophil count Substantial variation in FEV1 over time Substantial diurnal variation in PEFR
