Chronic Obstructive Pulmonary Disease (COPD) is a long term lung disease characterised by poor airflow. Emphysema and chronic bronchitis are the two conditions that fall beneath the COPD umbrella.
Presentation
Breathlessness
Chronic cough
Regular sputum production
Frequent 'winter bronchitis'
Wheeze
Weight loss
Fatigue
Key Differentials- Shortness of breath
Heart Failure
Asthma
PE
Pneumonia
Pneumothorax
History
Duration of symptoms?- COPD tends to be persistent and progressive
Level of breathlessness?- MRC dyspnoea scale (see table below)
Diurnal variation of symptoms?- more common in asthma
Smoking history- the primary cause of COPD in the UK
Occupation?- workplace dusts, chemicals and fumes increase the risk of COPD
Known Alpha 1 Antitrypsin Deficiency?- an inherited risk factor
Family History
| Grade | Degree of breathlessness |
|---|---|
| 1 | Only troubled by breathlessness on strenuous activity |
| 2 | Short of breath when hurrying or up a slight hill |
| 3 | Walks slower than someone of the same age on level ground OR has to stop to catch breath when walking at their own pace |
| 4 | Has to stop for breath after walking 100m or after a few minutes on level ground |
| 5 | Too breathless to leave the house or becomes breathless during activities such as washing or dressing |
Investigations
Spirometry
Used to measure the FEV1 (Forced expiratory volume in 1 second) and FVC (forced vital capacity- volume of air foricbly exhaled in one breath)
FEV1/FVC ratio <70% diagnostic of COPD
Chest Radiograph
Used mainly to exclude other differentials
Common COPD signs:
- Hyperinflated lungs
- Flattened diaphragm
- Bullae (if very emphysematous lungs)
FBC
Used to identity anaemia or polycythaemia
BMI
Should be calculated at time of diagnosis
ABG and pulse oximetry
Used to determine whether or not Oxygen therapy will be suitable
Sputum culture
If persistently purulent sputum
Other Investigations
Serial peak flow measurements- if asthma still a potential diagnosis
Alpha-1 antitrypsin testing- if presenting patient is young, has minimal smoking history or family history
Transfer factor for carbon monoxide (TLCO)- If symptoms seem disproportionate to the spirometric impairment
CT scan of thorax- To assess symptoms disproportionate to the spirometric impairment; to investigate abnormalities seen on radiograph; to assess suitability for surgery
ECG +/- Echocardiogram- if features of cor pulmonale
Assessing severity of COPD
FEV1 does not always fully reflect the extent of disability that COPD is causing a patient.
To fully assess severity take into account- degree of airflow obstruction, the frequency of exacerbations, and the following prognostic factors:
- FEV1
- TLCO
- breathlessness (MRC scale)
- health status
- exercise capacity (for example, 6-minute walk test)
- BMI
- partial pressure of oxygen in arterial blood (PaO2)
- cor pulmonale
GOLD STAGING
| Severity | FEV1% predicted |
|---|---|
| Mild (GOLD 1) | ≥80 |
| Moderate (GOLD 2) | 50-79 |
| Severe (GOLD 3) | 30-49 |
| Very severe (GOLD 4) | <30 |
Management
COPD patients are normally managed in the community by their GP unless they have an acute exacerbation which may result in admission to hospital
SMOKING CESSATION
The most important change a patient can make which will improve their symptoms and dramatically slow disease progression
Short acting bronchodilators
Short-acting beta2 agonists (SABA)
Inhaled agents
Short term relief of breathlessness and exercise limitation- can be taken up to 4 times a day
Regular use can improve FEV1
LABA's and LAMA's are preferred over short-acting agents except for patients with only occasional dysponoea
Long-acting bronchodilators
Combination of long-acting beta2 agonist (LABA) and long-acting muscarinic antagonist (LAMA) have been shown to significantly improve lung function and decrease exacerbation rates
e.g. Formoterol+glycopyrronium
Used once daily
Theophylline
Not recommended unless other long-term bronchodilators are unavailable or unaffordable
Inhaled corticosteroids (ICS)
Should be given to patients with moderate to very severe COPD or patients who are exacerbating
Give in combination with LABA
e.g. Budesonide/eformoterol (Symbicort)
Normal dosage is 2 puffs twice daily
Side effects:
Oral candidiasis, hoarse voice- inform patient to rinse mouth out after use
Triple Therapy
LABA+ ICS+ LAMA
Current evidence shows improved lung function compared to dual therapy however not conclusive
Oxygen therapy
Arterial hypoxaemia= PaO2 <55mmHG (8kPa) or SaO2 <88%
Long term administration of oxygen (> 15 hours per day) to patients with chronic respiratory failure has been shown to increase survival in patients with severe resting hypoxemia
Not shown to have health benefits in those with stable COPD and moderate resting/exercise-induced arterial desaturation
Aim to keep SaO2 >90%
Patients who are hypercapnic should be on very low oxygen levels if on it at all. It is not recommended COPD patients are given >2L oxygen. Monitor CO2 levels closely.
Antibiotics
Consider regular Macrolides in non-smokers with regular exacerbations despite appropriate therapy
PDE4 Inhibitor
Considered in patients with exacerbations despite LABA/ICS or LABA/LAMA/ICS therapy, chronic bronchitis and severe to very severe airflow obstruction
e.g. Roflumilast 500mcg po OD
Pulmonary Rehabilitation
A multidisciplinary programme that educates patients on how to manage their COPD and optimises patients physical and social performance
This should be offered and encouraged to all patients
