COPD Flashcards
define COPD?
chronic progressive lung disorder characterized by airflow obstruction often accompanied with chronic bronchitis and emphysema
what is chronic bronchitis?
- chronic cough and sputum production on most days for at least 3 months per year for over 2 consecutive years
what is emphysema?
- pathological diagnosis of permanent destructive enlargement of air spaces distal to the terminal bronchioles.
what is the aetiology of COPD?
two main causes: environmental damage and a-antitrypsin deficiency.
how does environmental damage cause COPD?
environmental toxins such as cigarette smoke can cause bronchial and alveolar damage.
this is common
when should 1antitrypsin deficiencybe considered?
in young patients who have never smoked before and present with COPD type symptoms
what is the pathophysiology of chronic bronchitis?
- the narrowing of the airways results in bronchiole inflammation, bronchial mucosal oedema, mucous hyper-secretion and squamous cell metaplasia
what is the pathophysiology of emphysema?
- it is the destruction and enlargment of the alveoli
- it leads to loss of elasticity which keeps the airways open in expiration
- larger spaces keep developing they are called bullae
epidemiology of COPD?
- it is really common
- presents in the middle age
- more common in males
presenting symptoms of COPD?
- chronic cough
- sputum production
- breathlessness
- wheeze
- reduced exercise tolerance
what are the signs of COPD on examination?
inspection
- respiratory distress
- use of accessory muscles
- barrel shaped over-inflated chest
- decreased cricosternal distance
- cyanosis
what are the signs of COPD on examination?
percussion
- hyper-resonant chest
- loss of liver and cardiac dullness
what are the signs of COPD on examination?
auscultation
- quiet breath sounds
- prolonged expiration
- wheeze
- rhonchi
- crepitations
what is rhonchi?
- it is rattling, continuous and low pitched breath sounds that sound like snoring
what are early signs of CO2 retention?
- bounding pulse
- warm peripheries
- asterixis
what are late signs of CO2 retention?
- cor pulmonale signs
- right ventricular heave
- raised JVP
- ankle oedema
what investigations should be carried out for COPD?
- spirometry
- CXR
- bloods
- ECG
- sputum and blood cultures
- a-antitrypsin levels
what might spirometry show?
- will show reduced PEFR
- will show reduced FEV1
- increased lung volumes
what might the CXR show?
- it may appear normal
- could show hyperinflation
- there are reduced peripheral lung markings
what might the bloods show?
- the FBC will show increased Hb and haematocrit
- this is due to secondary polycythaemia
- an ABG can show hypoxia
what might the ecg show?
- cor pulmonale
what might the sputum and blood cultures show?
- these are useful in acute infective exacerbations
what might measuring the x antitrypsin levels show?
- useful in checking in checking young patients who have never previously smoked
what is the overall management plan for COPD?
- stop smoking
- bronchodilators
- steroids
- pulmonary rehabilitation
- oxygen therapy
which bronchodilators should be used?
- short acting beta 2 agonists
- anticholinergics
- long acting beta 2 agonists
which steroids should be used?
- Inhaled beclamethasone
this should be considered in all patients with an FEV1 <50% or greater than 2 exacerbations each year - steroids should be avoided
when should oxygen therapy be used?
- if the patient has stopped smoking
when is oxygen therapy indicated?|
- when the PaO2 < 7.3 kPa on air during a period of clinical stability
- OR when PaO2 is between 7.3 - 8 but there are signs of secondary polycythemia or nocturnal hypoxaemia, peripheral oedema or pulmonary hypertension.
how should acute exacerbations be treated?
- 24% oxygen via a venturi mask
- percentage to be increased if there is hypoxia persists and there is no hypercapnia
- start antibiotics therapy if there is infection
- non invasive ventilation is sometimes necessary
- prevention of infective exacerbations using vaccines
what are the complications of COPD?
- acute respiratory failure
- infection
- pulmonary hypertension
- right heart failure
- pneumothorax (when the bullae rupture)
- secondary polycythaemia
what is the prognosis of patients with COPD?
- high morbidity
- 3 year survival of 90% if <60 and FEV1>50
- 3 year survival of 75 if >60 and FEV 40-49
