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
What does a chest x-ray show for COPD? (7)
- hyperinflation (>6 anterior ribs seen above diaphragm)
- flat hemidiaphragm
- reduced peripheral lung markings
- large central pulmonary arteries
- bullae (if large may mimic pneumothorax)
- hyperlucent lung fields
- elongated cardiac silhouette
When do we do ECG and echocardiogram for COPD?
Check for Cor Pulmonale - right atrial and ventricular hypertrophy
When do we test alpha-1-antitrypsin levels in COPD?
In young patients who have never smoked
What would we see on CT for A1AT deficiency compared to COPD?
- A1AT deficiency - emphysema in lower lobes
- COPD - emphysema in upper lobes
Why do we do FBC for COPD?
- assess severity of exacerbation
- may show: polycythaemia (haematocrit >55%), anaemia and leukocytosis
When do we do ABG for COPD?
- if acute exacerbation to check O2 and CO2 levels
- COPD causes CO2 retention –> type 2 respiratory failure
- PaCO2>50mmHg and/or PaO2<60mmHg = respiratory insufficiency
What are some differential diagnoses for COPD?
- asthma
- congestive heart failure - orthopnoea, bibasilar inspiratory crackles, BNP
- bronchiectasis - recurrent childhood infections, sputum, bronchial dilation
- TB - fever, night sweats, weight loss
- bronchiolitis - PFTs restrictive/mixed, younger
- upper airway dysfunction
- chronic sinusitis/postnasal drip - sinus pressure, rhinorrhoea, headache
- GORD
- ACEi induced chronic cough
- lung cancer (do CXR)
Describe the GOLD group method for categorising risk of exacerbations of COPD.
- GOLD group A: low risk (0-1 exacerbations per year, not requiring hospitalisation) and fewer symptoms (CAT<10)
- GOLD group B: low risk (0-1 exacerbations per year, not requiring hospitalisation) and more symptoms (CAT>=10)
- GOLD group E: high risk (>/=2 exacerbations per year or >/=1 requiring hospitalisation) and any level of symptoms
What is the first step of management for any patient with COPD?
Smoking cessation
- NRT (especially in pregnant women as varenicline and bupropion contraindicated)
- varenicline
- bupropion (contraindicated in epilepsy patients)
What are some non-pharmacological management methods for COPD? (3)
- annual influenza vaccine
- one-off pneumococcal vaccine
- pulmonary rehabilitation in patients who view themselves as functionally disabled by COPD
What is an example of a SABA (COPD)?
Salbutamol sulfate
What is an example of a SAMA (COPD)?
Ipratropium bromide
What is an example of a LABA (COPD)?
Salmeterol, Olodaterol (ultra long-lasting)
What is an example of a LAMA (COPD)?
Tiotropium bromide
What are some examples of a ICS (COPD), and when do we use these?
- budesonide, beclomethasone, fluticasone, mometasone
- consider if Hx of asthma, or blood eosinophils >300
What is the first-line treatment for GOLD group A, B and E COPD?
- GOLD group A: SABA/SAMA/LABA/LAMA
- GOLD group B: LABA+LAMA plus SABA/SAMA
- GOLD group E: LABA+LAMA or LABA+LAMA+ICS plus SABA/SAMA
What is the first-line treatment for GOLD group A/B/E COPD if persistent dyspnoea/exercise limitation after initial therapy?
- LABA+LAMA
- plus SABA/SAMA
- consider O2 therapy/ventilatory support
- consider mucolytic (e.g. acetylcysteine if chronic bronchitis)
- consider theophylline
- consider bronchoscopic intervention/surgery
- supportive care + pulmonary rehabilitation + palliative care
What is the first-line treatment for GOLD group A/B/E COPD if persistent exacerbations after initial therapy?
- LABA+LAMA or LABA+LAMA+ICS
- plus SABA/SAMA
- consider O2 therapy/ventilatory support
- consider roflumilast (oral phosphodiesterase-4 inhibitor if FEV1<50% and chronic bronchitis)
- consider azithromycin
- consider mucolytic
What are the 4 asthmatic features of COPD?
- Hx of asthma or atopy
- eosinophilia
- FEV1 variability min. 400ml
- diurnal variation in peak flow min. 20%
Describe the general first-line treatment algorithm for COPD.
- 1st line: bronchodilators - SABA or SAMA
- 2nd line if no asthmatic features/steroid responsiveness: add LABA+LAMA (if on SAMA, change to SABA)
- 2nd line if asthmatic features/steroid responsiveness: add LABA+ICS, have SABA/SAMA as required
- 3rd line final step: LABA+LAMA+ICS triple therapy if patients remain breathless/exacerbations (if already taking SAMA, discontinue and switch to SABA)
How do we manage an acute exacerbation of COPD?
- controlled O2 therapy: 24% Venturi mask
- aim for sats 88-92% for hypercapnia, 94-98% if pCO2 normal, PaO2>8kPa
- nebulised bronchodilators (salbutamol + ipratropium bromide)
- corticosteroids (oral prednisolone for 5 days or IV hydrocortisone if clinically unstable)
- IV theophylline
- Abx - if evidence of infection e.g. green sputum, signs of pneumonia –> amoxicillin, doxycycline or clarithromycin
- NIV (BiPAP) - if respiratory acidosis with high CO2 despite maximum medical treatment, pH 7.25-7.35
When is clarithromycin contraindicated?
Prolonged QT interval
What oral prophylactic Abx therapy is there for COPD and when do we use this?
Azithromycin, if they meet criteria for recurrent infections:
- patient should not smoke
- have optimised standard treatments
- continue to have exacerbations (3+ requiring steroids, and 1+ requiring hospital in past year)
- (CT thorax - exclude bronchiectasis)
- (sputum culture - exclude atypical infections and TB)
What should you be careful of when giving azithromycin?
Can cause QT interval prolongation –> request ECG
What is the most common cause of an acute exacerbation of COPD?
Haemophilus influenzae
What do you give to critically ill (including CO2 retaining) COPD patients?
High flow oxygen –> reservoir mask at 15L/min
Who do we offer long term oxygen therapy to (LTOT) for COPD?
- assess ABG on two occasions at least 3 weeks apart to show:
- pO2 <7.3kPa
- OR pO2 7.3-8kPa AND secondary polycythaemia/peripheral oedema/pulmonary hypertension
Why can supplemental oxygen be harmful to COPD patients?
- reduces respiratory drive –> hypoventilation –> CO2 retention
- patient will often already have chronic respiratory acidosis indicated by raised HCO3-
When is oral theophylline recommended for COPD and what should we check first?
- NICE only recommends theophylline after trials of short and long-acting bronchodilators or to people who cannot used inhaled therapy
- check U&Es and LFTs before starting
- dose should be reduced if macrolide or fluoroquinolone antibiotics are co-prescribed
When should mucolytics be considered for COPD?
In patients with a chronic productive cough and continued if symptoms improve
When should PDE-4 inhibitors be considered for COPD?
- oral PDE-4 inhibitors such as roflumilast reduce the risk of COPD exacerbations in patients with severe COPD and a history of frequent COPD exacerbations
- NICE recommend if:
- the disease is severe, defined as a forced expiratory volume in 1 second (FEV1<50%) after a bronchodilator of less than 50% of predicted normal, and
- the person has had 2 or more exacerbations in the previous 12 months despite triple inhaled therapy with a long-acting muscarinic antagonist, a long-acting beta-2 agonist and an inhaled corticosteroid (LABA+LAMA+ICS)
What do we give COPD patients with frequent exacerbations to take home? (2)
- antibiotics
- prednisolone
What are some complications of COPD?
- Cor Pulmonale (right-sided heart failure)
- recurrent pneumonia
- depression
- lung cancer
- pneumothorax (secondary to bullae rupture)
- respiratory failure
- anaemia
- polycythaemia
- receiving too much O2 –> acute respiratory acidosis on top of chronic acidosis with compensatory metabolic alkalosis (= elevated HCO3-)
How do we manage Cor Pulmonale (right-sided heart failure) due to COPD? (2)
- loop diuretic for oedema
- consider long-term oxygen therapy
- NOT recommended: ACEi, calcium channel blockers, alpha blockers
What is the reported prognosis of COPD based on?
FEV1 - significant correlation between increased FEV1 and lower risk of COPD exacerbation
How do we manage a non-severe COPD exacerbation?
- increase the frequency of bronchodilator use and consider giving via a nebuliser
- give 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 one of the following oral antibiotics first-line: amoxicillin or clarithromycin or doxycycline.
How do we manage a COPD exacerbation requiring secondary care?
- O2 therapy: 28% Venturi mask at 4 l/min and aim for an oxygen saturation of 88-92%
- nebulised bronchodilator
- steroid therapy - oral prednisolone/IV hydrocortisone
- IV theophylline if bronchodilators do not work
- if type 2 respiratory failure occurs –> non-invasive ventilation –> BiPAP (EPAP 4-5cm H2O, IPAP 10-15cm H2O)
