Clinical Features of COPD Flashcards
Define COPD
A chronic slowly progressive airflow obstruction that shows little change over months. Most impairment is fixed but some can be reversed with bronchodilators
How does COPD relate to Chronic Bronchitis & emphysema?
Most people with COPD have it as a result of chronic bronchitis & emphsema. Some also have Asthma.
What obstructs the airways in COPD?
- Fibrosis thickens the airway walls
- Mucuous & inflammatory exudate blocks the airway
- Lymphoid follicles in severe disease
- Loss of eleasticity due to broken alveolar attachments.
Why defines chronic bronchitis?
Coughing up sputum almost every day for 4 or more months of the year for 2 or more years
What are the common causes for COPD?
- Smoking ~85%
- Chronic Asthma
- Maternal Smoking
- Air pollution
- Occupation
- Genetics
What occupations can lead to COPD?
Mining/tunneling
Construciton
Work with plastics, leather, textiels
What genetic conditions can lead to COPD?
Enzyme deficiencies,
Specifically Alpha1-antitrypsin deficiency results in emphysema.
What does alpha1-antitrypsin normally do?
Neutralises the enzymes released by neutrophils so they dont damage the tissue or cause inflammation
What level of smokin is indicative of COPD?
> 20 pack years
How does FEV1 decline in a normal person and a smoker?
~30ml/yr
In a smoker more like 50-80ml/yr
How do we rule out asthma when diagnosisng a patient?
If the symptoms are constant then its not asthma
When would we consider lung cancer or bronchiecstasis over COPD?
If there is harmoptysis
What is smoker’s cough?
Coughing up clear or mucoi sputum, gradually becomes more regular over time.
(almost all resolve if they stop smoking)
What are the common symptoms of COPD?
Wheeze Weight loss in severe disease Peripheral Oedema (due to cor pulmonale via respiratory failure) SOBOE Cough
What illnesses do you look for in a history when diagnosing COPD?
Childhood Asthma
Respiratory Disease
Ischaemic heart failure
Why would you ask about the effect of previous breathing meds?
To see if theyre effects correlate with what youd expect form COPD. As opposed to asthma etc
What signs might you see in the clinic?
Breathless with pursed lips and accessory muscle involvement. Cyanosis CO2 tremor Hyperinflated chest Larygeal descent Slow expiration Palapable Liver
How do we treat a CO2 trmor?
With a B-agonist
How far can the larynx descend?
As far as the manubrium
What FEV1 & FEV1/FVC valuse are expected in COPD?
- FEV1 < 80% of predicted
- FEV1/FVC < 70% of predicted
What are the grades of airflow obstruction as measured by FEV1?
80% or above - Fine
50-79% - Moderate AFO
30-49% - Severe AFO
<30% - Very Severe AFO
What is the point of pulmonary function tests?
To detect evidence of emphysema
