GP/ Medicine - COPD Flashcards
What is COPD?
Persistent respiratory symptoms + airflow obstruction that is progressive and irreversible
Limited reversibility after bronchodilators
An umbrella term for emphysema + chronic bronchitis
Give 5 risk factors/ causes for COPD
Smoking
Air pollution
Occupational exposure to coal, dusts, fumes, and chemicals
Alpha-1 antitrypsin deficiency
Developmental problems i.e. prematurity or low birth weight
What is the MOST COMMON CAUSE of COPD?
Smoking
What is the pathopathysiology of COPD?
- Emphysema - Destruction of alveolar wall leading to abnormal enlargement of air sacs –> reduced surface area for gaseous exchange; Loss of elastin causes reduced elastic recoil of the lungs and increased lung compliance
- Chronic bronchitis - Mucous gland hyperplasia –> mucus hypersecretion; Loss of ciliary function –> impaired mucus clearance
Give 3 complications of COPD
Cor pulmonale (COPD –> hypoxia –> hypoxic vasoconstriction of pulmonary capillaries –> pulmonary hypertension –> Cor pulmonale)
Type 2 respiratory failure
Lung cancer (think about smoking of the BIG CAUSE)
Frequent respiratory infections (e.g. pneumonia)
Secondaru pneumothorax
How do you diagnose COPD?
Clincal features + post-bronchodilator spirometry
What symptoms would a patient with COPD present with?
Symptoms:
- Chronic productive cough with sputum
- Dyspnoea - progressive and worse on exertion
- Wheeze
- Reduced exercise tolerance
- Weight loss, fatigue
- Frequent lower respiratory tract infections
What signs would a patient with COPD present with?
Hyperinflated lungs (barrel chest) - anteroposterior: lateral diameter = 1:1
Hyperresonant percussion (due to air being trapped inside lungs)
Reduced lung expansion
Decreased cricosternal distance
Purse lip breathing
Use of accessory muscles of respiration
Central and peripheral cyanosis
Flapping tremour suggestive of CO2 retention - Type 2 resp failure
Raised JVP, ankle swelling, hepatomegaly, parasternal heave suggestive of Cor Pulmonale
What score do you we use to grade the severity of SOB in COPD?
MRC dyspnoea score
What are the different categories in MRC dyspnoea score?
Grade Level of activity
1 Breathlessness only on strenuous exercises
2 Breathlessness when hurrying or walking up a slight hill
3 Walks slower than normal on level ground due to breathlessness, or has to
stop for breath when walking at own pace
4 Stops for breath after walking 100 m or after a few minutes on level ground
5 Too breathless to leave the house; breathless when dressing or undressing
What examinations would you carry out in a GP practice?
- Respiratory and Cardiovascular examinations
- Including checking for signs of cor pulmonale - raised JVP, ankle swelling, hepatomegaly, parasternal heave
Basic obs:
- HR, BP, SaO2 (pulse oximetry), Temperature
- Check BMI (can compare this with previous readings to determine the amount of weight loss)
What findings on a spirometry would help confirm a diagnosis of COPD?
Post-bronchodilator spirometry:
FEV1 < 80% predicted, OR
FEV1/ FVC < 0.7
Other than FEV1 and FEV1/ FVC readings, what other measurements on a spirometry will reinforce the diagnosis of COPD?
Increased FRC, RV, TLC, but decreased IRV
In SHx, the impact of symptoms on daily life and occupation is often asked. What is a more objective way of assessing this?
COPD assessment test (CAT)
What differential diagnosis must you consider if a young patient presents with symptoms of COPD?
Alpha-1 antitrypsin deficiency
Pneumonia
Asthma
What questions would you ask about cough and sputum production?
Onset, duration, frequency, diurnal variation of cough
Colour and volume of sputum
Any blood in it?
What in the PMHx would you ask in someone with suspected COPD?
Asthma
Other lung or liver diseases
Cardiovascular disease
Any previous acute hospital admissions or exacerbations
What investigations would you do for COPD patients in a primary care setting?
Blood tests - FBC shows anaemia or polycythaemia, and to rule out infection
Post-bronchodilator spirometry showing FEV1 < 80% predicted, or FEV1/FVC < 0.7
Request CXR shows hyperinflated lungs (> 6 anterior ribs or > 10 posterior ribs at MCL at diaphragm level) and hyperlucent lungs (bullae), flat hemidiaphragm; it also helps to rule out complications of COPD e.g. pneumonia, secondary pneumothorax, lung cancer, and cardiomegaly in cor pulmonale
Request ECG for cor pulmonale
BMI
What other investigations can you also do?
ABG - may show type 1 or 2 respiratory failure
Sputum culture
ECG, Echo, BNP - may show RV hypertrophy (Cor pulmonale)
Alpha-1 antitrypsin deficiency if young patient with early onset of COPD symptoms
Where post-bronchodilator FEV1/FVC ratio is less than 0.7, severity of airflow obstruction is graded according to reduction in FEV1 compared to appropriate reference values (based on age, sex, height and ethnicity). What are the gradings?
Stage 1 (mild) - FEV1 < 80% predicted
Stage 2 (moderate) - FEV1 < 50-79% predicted
Stage 3 (severe) - FEV1 < 30-49% predicted
Stage 4 (very severe) - FEV1 < 30% predicted or FEV1 < 50% with respiratory failure
What are the differential diagnoses?
Asthma
Lung cancer
Heart failure
Bronchiectasis
Compare and contrast Asthma vs COPD
Asthma COPD
Good reversibility after bronchodilators Limited reversibility after bronchodilators
Dry cough Productive cough with sputum
Symptoms worse at night Symptoms constant throughout day and night
Acute onset Chronic onset and progressive
First onset usually at young age First onset usually elderly patients who smoke
Hx of atopy Hx of smoking
Spirometry shows obstructive pattern Spirometry shows mixed obstructive and
restrictive pattern
What is the management for stable COPD?
Non-pharmacological management:
- Lifestyle changes - smoking cessation (offer nicotine replacement therapy), more exercises, healthy diet
- Pneumonoccoal and influenza vaccinations
- Pulmonary rehabilitation- if functionally disabled by COPD or MRC grade >/= 3) or a recent acute exacerbation requiring hospitalisation
- Optimise treatment for comorbidities e.g. asthma, other lung conditions, cardiovascular disease, diabetes, HTN
Pharmacological mangement:
- 1st line: SABA/ SAMA
- If patients remain breathless or have exacerbations despite using SABA/ SAMA, the next step is determined by whether the patient has ‘asthmatic features/ features suggesting steroid responsiveness’
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If no asthmatic features/ features suggestive of steroid responsiveness:
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Add LABA + LAMA
- If patient already taking a SAMA, discontinue and switch to a SABA
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Add LABA + LAMA
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If they have asthmatic features/ features suggestive of steroid responsiveness:
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Add LABA + ICS (these two can be given as a single combination inhaler called Fostair)
- If patients remain breathless or have exacerbations, add LAMA (triple therapy)
- If already taking a SAMA, discontinue and switch to a SABA
- If patients remain breathless or have exacerbations, add LAMA (triple therapy)
-
Add LABA + ICS (these two can be given as a single combination inhaler called Fostair)
-
If no asthmatic features/ features suggestive of steroid responsiveness:
- If patients remain breathless or have exacerbations despite using SABA/ SAMA, the next step is determined by whether the patient has ‘asthmatic features/ features suggesting steroid responsiveness’
- Other add-on treatments in COPD:
- Oral theophylline - only recommended after trials of short and long-acting bronchodilators or to people who cannot use inhalers
- Oral prophylactic Abx (azithromycin)
- Discuss with a respiratory specialist first
- CT thorax (to exclude bronchiectasis) and sputum culture (to exclude TB and atypical infections) must be done prior to prescribing
- An ECG is needed to exclude prolonged QT
- Oral mucolytics - if a patient develops chronic productive cough with sputum
- If Cor pulmonale, give loop diuretics + LTOT
(Note that Oral corticosteroids should NEVER be offered for maintenance treatment of COPD in primary care)
Long-term oxygen therapy (LTOT)
- Need to be used for at least 15 hrs/ day
- Offer LTOT if pO2 < 7.3 kPa, or < 8 kPa with cor pulmonale, peripheral oedema, or polycythaemia
- Patients must be non-smokers (due to risk of fire and explosion) and do not have CO2 retention
- NIV (BIPAP) if hypercapnic on LTOT
Lung volume reduction surgery to treat hyperinflated lungs
What are the criteria that suggest the presence of asthmatic features or features of steroid responsiveness?
Previous diagnosis of asthma or atopy
High blood eosinophil count
Substantial variation in FEV1 over time (at least 400 mL)
Substantial diurnal variation in PEFR (at least 20%)
What are the names of the drugs for SABA, SAMA, LABA, and LAMA?
SABA = Salbutamol
SAMA = Ipratropium bromide
LABA = Salmeterol / formoterol
LAMA = Tiotropium
ICS = Inhaled corticosteroids
What do you want to check if a patient is on an inhaler? And What do you want to minimise in someone with 2 or more inhalers?
Check inhaler technique
Check patient compliance/ adherence
Minimise the number and type of inhalers used by each person as much as possible, e.g. use a combination inhaler (Fostair)
What is Fostair inhaler?
LABA + ICS
It’s usually given when patients are already on 2 inhaler medications, and a third one needs to be given.
When would you NOT refer the patient for pulmonary rehabilitation?
Cannot walk
Unstable angina or recent MI
When should you refer a patient with COPD to a respiratory specialist?
Lung cancer is suspected
Cor pulmonale is suspected
Very severe COPD (FEV1 < 30% predicted)
Frequent chest infections
Diagnostic uncertainty
What advice would you give to the patient with stable COPD?
Advice:
- Stops smoking
- Encourage exercises
- Check inhaler techniques
- Advise to carry inhalers and other appropriate medication wherever they go
- Educate on symptoms of acute exacerbation of COPD
- Advise them about the side effects of each medication
- SABA - tachycardia, palpitations, hypokalaemia, tremor
- SAMA - dry mouth, cough, constipation, N&V
- Safety netting: If their conditions deteriorate e.g. medications no longer effective or if there is development of new symptoms, arrange to see their GP or call 999
What are the clinical features suggestive of an acute exacerbation of COPD?
Worsening dyspnoea
Worsening cough with increased sputum volume and purulence
Worsening wheeze
Chest tightness, reduced exercise tolerance
Fever
URTI in the past 5 days
Increased RR or HR 20% above baseline
Acute confusion, cyanosis, peripheral oedema
What examinations would you do for AECOPD?
Respiratory and cardiovascular examinations
Check BP, HR, SaO2 and Temperature
Assess for confusion
What investigations would you do in AECOPD?
Blood tests
ABG
CXR
ECG, Echo
Sputum culture if purulent
Blood culture if fever
What is the acute management for AECOPD?
- ABCDE
- Controlled oxygen via Venturi mask (24 or 28%), aim at SaO2 88-92%
- Nebulised bronchodilators - salbutamol and ipratropium bromide
- Steroids - oral prednisolone 30 mg STAT and then OD for 7 days
- Antibiotics ONLY if raised CRP/ WCC or purulent sputum - give amoxicillin (if no underlying lung disease) or co-amoxiclav (if respiratory failure or cor pulmonale)
- If penicillin allergic, give doxycycline or clarithromycin (avoid in long QT)
- CXR
- If not improving, consider:
- IV aminophylline
- NIV if type 2 respiratory failure and acidotic (pH 7.25-7.35)
- ITU referral for invasive ventilation if pH < 7.25
What are the two most common microorganisms that cause AECOPD?
Haemophilus influenza (that’s why patient have yearly influenza vaccine)
Streptococcus pneumoniae
Moraxella Catarrhalis
Rhinovirus
