Condition- COPD Flashcards
What is COPD?
A chronic progressive lung disorder characterised by airflow obstruction with little or no reversibility. It encompasses chronic bronchitis and emphysema
What are the values for the FEV1/FVC ratio and % FEV1 which can be used to characterise COPD?
- FEV1/FVC post bronchodilator of <0.7
- FEV1 (of predicted) <80%
What is the main risk factor for COPD? List some other risk factors too
- SMOKING
- Air pollution
- Occupational Exposures
- Genetics- a1 antitrypsin deficiency
What happens to the airways in chronic bronchitis?
- Inflammation (-> hypertrophy + hyperplasia of goblet cells)
- Excess mucus production in the small and large airways
- Shorter cilia + less motile => mucus congestion
==> Airway obstruction
How is chronic bronchitis defined?
Defined CLINICALLY as chronic cough and sputum production on most days for at least 3 months per year over 2 consecutive years.
This means inspired air becomes trapped in the lungs which leads to hyperexpansion of the chest
How is emphysema defined?
Defined HISTOLOGICALLY as permanent enlarged air spaces distal to the terminal bronchioles, with destruction of alveolar walls.
In a young patient who has never smoked and comes in presenting with symptoms of COPD what might they have?
a1-antitrypsin deficiency
Why do you get right heart failure in COPD pts?
- Low ventilation in some areas of the lungs
- Blood vessels vasoconstrict in these areas to redirect blood to better ventilated areas
- Since this happens in large areas of lung => increased vascular resistance => Pulmonary hypertension
- Right heart must work harder to pump blood to lungs => COR PULMONALE + RHF
List some of the presenting symptoms of COPD
- Chronic productive cough
- SOBOE
- Wheeze
List some of the signs of COPD on clinical examination
GENERAL INSPECTION:
- Tripod stance
- Resp distress
HANDS:
- Peripheral cyanosis
- Hepatic flap
FACE:
- Pursed lips breathing
NECK:
- Reduced cricosternal distance
- May have elevated JVP if RHF (+ peripheral oedema + Heaves)
CHEST:
- I: Barrel chest, use of accessory muscles to breathe
- P: Bilaterally reduced chest expansion
- P: Hyper-resonant, loss of liver dullness
- A: Expiratory wheeze, quiet breath sounds, prolonged expiration
Why do patients with COPD have prolonged expiration times?
Prolonged expiration due to loss of elastic recoil of alveoli due to emphysematous changes where enzymes break down alveolar elastins and collagens.
What is the gold standard test for diagnosing COPD- what would the positive results be?
SPIROMETRY
- FEV1/FVC: reduced because reduction in FEV1 is more notable than FVC
- Post bronchodilator FEV1/FVC <0.7
- Increased lung volumes
What might you see on a CXR of someone with COPD?
- Hyperinflation (> 6 anterior ribs, flattened hemidiaphragm)
- Bullae
- Large central pulmonary arteries
- Elongated cardiac silhouette
Why might you conduct a blood test in pts with COPD?
Might check FBC to check for secondary polycythaemia due to hypoxia
Why might you conduct an ECG in patients with COPD?
To check for Cor Pulmonale and RHF