What is Chronic Obstructive Pulmonary Disease (COPD)?
COPD is a common progressive disorder
characterised by irreversible airway obstruction (FEV1 <80% ; FEV1/FVC < 0.7).
Both emphysema and chronic bronchitis eventually leads to: => airflow limitation, => destruction of lung parenchyma => resultant hyperinflation of lungs, => ventilation/perfusion mis-match, => increased work of breathing => breathlessness
What is emphysema and bronchitis?
- Emphysema is permanent loss of parenchymal lung tissue
=> loss of alveoli decreases capacity for gas transfer
=> loss of lung elastic recoil results in an increased total lung volume
=> expiratory airflow limitation and air trapping
- Chronic Bronchitis clinically defined as cough and sputum production on most days for 3 months of 2 successive years.
What are the causes for COPD?
- Smoking cigarettes = 90% of COPD in developed countries
* 10-20% smokers develop COPD - suggests there is an underlying susceptibility.
=> risk of COPD also increases with pipe, water pipe and marijuana smoking
=> risk also increases with passive smoking
- Occupational exposure to
=> Dust i.e. coal, grains and silica
=> Certain fumes or chemicals i.e. welding fume, isocyanates, and polycyclic aromatic hydrocarbons
- around 20-30% of COPD due to occupational exposure
3. Air pollution - exposure to high levels of indoor air pollutants from burning wood and biomass materials i.e coal
4. Alpha1 anti-trypsin deficiency
5. Maternal smoking, pre-term birth, childhood passive smoking
6. Asthma ?
What are the symptoms of COPD?
Breathlessness - typically persistent, progressive over time, and worse on exertion.
Chronic/recurrent cough.
Regular sputum production.
Frequent lower respiratory tract infections.
Wheeze.
Other symptoms:
Weight loss, anorexia and fatigue — common in severe COPD but other causes must be considered.
Waking at night with breathlessness.
Ankle swelling – consider cor pulmonale.
Reduced exercise tolerance.
*severe cases = right sided heart failure may develop
What are the signs of COPD?
Cyanosis.
Raised jugular venous pressure
Peripheral oedema (may indicate cor pulmonale).
Cachexia.
Hyperinflation of the chest.
Use of accessory muscles and/or pursed lip breathing.
Wheeze and/or crackles on auscultation of the chest.
How is COPD diagnosed?
- Spirometry is required for confirmation of diagnosis:
=> A post bronchodilator FEV1/FVC less than 0.7 confirms persistent airflow obstruction
- Chest x-ray
=> hyperinflation
=> bullae: if large, may sometimes mimic a pneumothorax
=> flat hemidiaphragm
- also important to exclude lung cancer, TB, bronchiectasis, heart failure
3. Full blood count: exclude secondary polycythaemia or anaemia
4. BMI
Additional tests depending on clinical situation:
=> Sputum culture – if sputum is purulent and persistent
=> Serial home peak flow measurements – to exclude asthma if diagnosis is in doubt.
=> ECG and serum natriuretic peptides – if cardiac disease or pulmonary hypertension are suspected.
Echocardiogram may also be indicated.
=> CT thorax – if symptoms seem disproportionate to spirometry measurements; another diagnosis (such as fibrosis or bronchiectasis) is suspected, or an abnormality on chest x-ray.
=> Serum alpha-1-antitrypsin.
Consider alpha-1-antitrypsin deficiency in people with early onset of symptoms, minimal smoking history or a positive family history.
*Referral to a specialist for management and screening of family members is required if alpha-1-antitrypsin deficiency is identified.
How is COPD categorised / staged?
Severity of COPD is categorised using FEV1
Stage 1: Mild COPD**
=> Post bronchodilator FEV1/FVC <0.7
=> FEV1 (of predicted) >80%
**symptoms should be present to diagnose mild copd
Stage 2: Moderate COPD
=> Post bronchodilator FEV1/FVC <0.7
=> FEV1 (of predicted) 50 - 79%
Stage 3: Severe COPD
=> Post bronchodilator FEV1/FVC <0.7
=> FEV1 (of predicted) 30-49%
Stage 4: Very severe COPD
=> Post bronchodilator FEV1/FVC <0.7
=> FEV1 (of predicted) <30%
How can COPD be prevented / lifestyle managements?
- Smoking cessation advice: including offering nicotine replacement therapy, varenicline or bupropion
=> end passive smoking (occupation therapist / social services help with setting) - Moderate exercise regularly
- Eat a healthy diet
- Vaccinations:
=> Annual influenza vaccination
=> One-off pneumococcal vaccination
*helps prevent exacerbation of COPD - Avoid close contact with people who have respiratory infections
- Avoid excessive heat, cold or high altitudes
- Avoid exposure to environmental irritants
- Learn breathing techniques and relaxation techniques
Withdrawal symptoms (irritability, aggression, depression, restlessness, poor concentration, increased appetite, light headedness, disturbed sleep, nicotine cravings) experienced within 48 hours to 4 weeks of stopping smoking.
What is smoking cessation and how does this help?
Patients should be offered:
- Nicotine replacement therapy (NRT) OR
- Varenicline OR
- Bupropion
TARGET STOP DATE => NRT, varenicline or bupropion should normally be prescribed as part of a commitment to stop smoking on or before a particular date
Prescription of NRT, varenicline or bupropion should be sufficient to last only until 2 weeks after the target stop date.
Normally, this will be after 2 weeks of NRT therapy, and 3-4 weeks for Varenicline and Bupropion.
Further prescriptions should be given only to people who have demonstrated that their quit attempt is continuing
if unsuccessful using NRT, varenicline or bupropion, do not offer a repeat prescription within 6 months
- Nicotine Replacement Therapy
=> Adverse effects: nausea & vomiting, headaches, flu-like symptoms
=> NICE recommend offering a combination of nicotine patches and another form of NRT (such as gum, inhalator, lozenge or nasal spray) to people who show a high level of dependence on nicotine or who have found single forms of NRT inadequate in the past
- Bupropion
=> Norepinephrine and dopamine reuptake inhibitor, and nicotinic antagonist
should be started 1 to 2 weeks before the patients target date to stop
small risk of seizures
=> Contraindicated in epilepsy, pregnancy and breast feeding
- Varenicline
=> Nicotinic receptor partial agonist
=> Should be started 1 week before the patients target date to stop
=> The recommended course of treatment is 12 weeks (but patients should be monitored regularly and treatment only continued if not smoking)
=> Adverse effect: Nausea (most common), headache, insomnia, abnormal dreams
=> Varenicline should be used with caution in patients with a history of depression or self-harm.
=> Contraindicated in pregnancy and breast feeding
NICE recommended that all pregnant women should be tested for smoking using carbon monoxide detectors.
=> All women who smoke, or have stopped smoking within the last 2 weeks, or those with a CO reading of 7 ppm or above should be referred to NHS Stop Smoking Services.
Interventions:
=> First-line interventions in pregnancy is CBT, motivational interviewing or structured self-help and support from NHS Stop Smoking Services
=> NRT is used if the above measures fail - little evidence for use in pregnancy.
=> Varenicline and Bupropion are contraindicated
What is pulmonary rehabilitation?
Pulmonary rehab is a exercise & education programme that helps patients with COPD stay active; made up of two components:
=> a physical exercise programme
=> information on looking after your body and your lungs, and advice on managing your condition and your symptoms, including feeling short of breath
PR helps to:
=> improve your muscle strength so you can use O2 more efficiently and become less breathless
=> cope better with feeling of breathlessness
=> improve your fitness so you feel confident with everyday tasks
=> feel better mentally
=> understand your condition and how to manage it better
EVIDENCE: helps people walk further, helps them feel less tired and breathless when carrying out day-to-day activities => higher activity & exercise levels
*won’t improve your lung function / breathing tests / disease
Anyone who needs it (functionally disabled by COPD) can be referred by GP
Team of different HCP including physiotherapists, nurses, occupational therapists to help you exercise safely and at the right level for you. Most enjoy the course and it helps build confidence. It’s a great fun meeting others in a similar situation.
Pulmonary rehab course lasts 6-8 weeks, with 2 sessions about 2 hours each week. Group of 8-16 people.
=> First hour = exercise
=> Second hour = discussion
- why exercise is so important for people with lung conditions
- ways to be more positive about exercise
- how to use breathing techniques during physical activity or when you feel anxious
- how to manage anxiety and low mood
- how to use your inhalers and other medicines
- how to eat healthily
- how to stop smoking
- what to do when you’re unwell
What is the management for stable COPD
- First line: SABA or SAMA (short acting muscurinic antagonist) as required
- Second step is dependent on presence of asthmatic features / features suggesting steroid responsiveness. The criteria is:
=> previous diagnosis of asthma or atopy
=> higher blood eosinophil count (FBC during investigation)
=> substantial variation in FEV1 over time (at least 400ml)
=> substantial diurnal variation in peak expiratory flow (at least 20%)
2b. No asthmatic features/ features suggesting steroid responsiveness
=> Add a LABA + LAMA *if already on SAMA, stop & switch to SABA as required
2c. Asthmatic features/ features suggesting steroid responsiveness
=> LABA + ICS + SABA or SAMA as required
=> Triple therapy i.e. LAMA, LABA, ICS if patient remains breathless or has exacerbations *if on SAMA, stop and switch to SABA as required
- NICE recommends combined inhalers where possible
3. Oral theoplylline - after trials of short and long acting bronchodilators or people who can’t use inhaled therapy.
- Oral prophylactic antibiotics therapy:
=> Azithromycin prophylaxis is recommended in select patients
=> Patients should not smoke, have optimised standard treatments and continue to have exacerbations
=> CT thorax (to exclude bronchiectasis) and sputum culture (to exclude atypical infections and tuberculosis)
=> LFTs and ECG to exclude QT prolongation (azithromycin can prolong the QT interval) - Mucolytics - considered in patients with chronic productive cough + continued if symptoms improve.
Examples of SAMA: Ipratropium, Oxytropium
Examples of LAMA: Tiotropium, Glycopyrrolate, Umeclidium
Examples of SABA: Abuterol, Salbutamol, Terbutaline, Bitolterol, Levabuterol
Examples of LABA: Salmeterol, Formoterol, Olodaterol
Examples of ICS: Fluticasone, Budesonide, Mometasone, Beclomethasone, Ciclesonide, Flunisolide
How is Cor Pulmonale as a complication of COPD managed?
- Features: Peripheral oedema, raised jugular venous pressure, systolic parasternal heave, loud P2
- Loop diuretic for oedema, consider long term O2 therapy
- ACE-i, CCB, alpha blockers not recommended
Which factors may improve survival in patients with stable COPD?
- Smoking cessation - the single most important intervention in patients who are still smoking
- Long term oxygen therapy in selected patients
- Lung volume reduction surgery in selected patients
What are the features of acute COPD exacerbation and what is the most common causative organism?
Features:
=> increase in dyspnoea, cough, wheeze
=> increase in sputum suggestive of an infective cause
=> patients may be hypoxic and sometimes have acute confusion
The most common bacterial organisms that cause infective exacerbations of COPD are:
- Haemophilus influenzae (most common cause)
- Streptococcus pneumoniae
- Moraxella catarrhalis
Respiratory viruses account for around 30% of exacerbations, with the human rhinovirus being the most important pathogen
How is COPD exacerbation managed?
- Increase frequency of bronchodilator use and consider giving via a nebuliser
- Prednisolone 30 mg daily for 5 days
(It is common practice for all patients with an exacerbation of COPD to receive antibiotics.
NICE do not support this approach. They recommend giving oral antibiotics ‘if sputum is purulent or there are clinical signs of pneumonia’)
=> the BNF recommends oral antibiotics first-line: amoxicillin or clarithromycin or doxycycline.
When to refer a person with COPD?
Lung cancer suspected
Very severe / rapidly worsening COPD i.e. FEV1 less than 30% predicted
Cor pulmonale
<40 years old and/or family hx of alpha-1 anitrypsin deficiency
Others:
=> Oxygen therapy.
=> Long-term non-invasive ventilation.
=> Nebulizer therapy or long-term oral corticosteroids.
What are the complications of COPD?
Reduced quality of life and increased morbidity and mortality
Depression and anxiety
Cor pulmonale — right heart failure secondary to lung disease caused by pulmonary hypertension as a consequence of chronic hypoxia.
Frequent chest infections (including pneumonia).
Secondary polycythaemia — overproduction of red blood cells as a result of hypoxia.
Respiratory failure — due to increased airway resistance.
Pneumothorax — due to abnormal lung parenchyma and formation of bulla.
Lung cancer — COPD may increase the risk of lung cancer.
Muscle wasting and cachexia — due to multiple factors including effects of disease (such as breathlessness and anorexia), increased nutritional requirements and psychological factors.
=> Muscle wasting and cachexia are associated with reduced exercise tolerance, poor health status and increased risk of mortality in people with COPD.
Medical Research Council (MRC) dyspnoea scale
Grade 1: Not troubled by breathlessness except during strenuous exercise
Grade 2: Short of breath when hurrying or walking up a small hill
Grade 3: Walks slower than contemporaries on the level because of breathlessness, or has to stop for breath when walking at own pace
Grade 4: Stops for breath after walking 100m or a few minutes on the level
Grade 5: Too breathless to leave the house, or breathless when dressing / undressing
Differentials for COPD
Asthma — COPD and asthma can be difficult to distinguish clinically and may co-exist.
Bronchiectasis — clinical features include copious sputum, frequent chest infections, a history of childhood pneumonia, and coarse lung crepitations.
Heart failure — clinical features include breathlessness when lying flat, a history of ischaemic heart disease, and fine lung crepitations.
Lung cancer — consider if the person has a persistent cough, haemoptysis, weight loss, or persistent hoarse voice.
Interstitial lung disease (such as asbestosis, pneumoconiosis, fibrosing alveolitis, or sarcoidosis) — clinical features include a dry cough and fine lung crepitations.
Anaemia — clinical features include fatigue, breathlessness, and palpitations.
Anaemia - B12 and folate deficiency.
Tuberculosis (TB) — clinical features include persistent productive cough, which may be associated with breathlessness and haemoptysis. May co-exist with COPD.
Cystic fibrosis
Upper airway obstruction
When is Long-term Oxygen Therapy needed in COPD?
Assess patients if any of the following:
=> Very severe airflow obstruction (FEV1 < 30% predicted). Assessment should be ‘considered’ for patients with severe airflow obstruction (FEV1 30-49% predicted)
=> cyanosis
=> polycythaemia
=> peripheral oedema
=> raised jugular venous pressure
=> oxygen saturations less than or equal to 92% on room air
Assessment is done by measuring ABG on 2 occasions at least 3 weeks apart in patients with stable COPD on optimal management.
Offer LTOT to patients with a pO2 of < 7.3 kPa or to those with a pO2 of 7.3 - 8 kPa and one of the following:
- secondary polycythaemia
- peripheral oedema
- pulmonary hypertension
Patients who receive LTOT should breathe supplementary oxygen for at least 15 hours a day
Acutely unwell patients: COPD oxygen management
Prior to availability of blood gases, use a 28% Venturi mask at 4 l/min and aim for an oxygen saturation of 88-92% for patients with risk factors for hypercapnia but no prior history of respiratory acidosis
Adjust target range to 94-98% if the pCO2 is normal
Patients at risk of hypercapnia e.g. COPD => 88-92%
