COPD Flashcards
1
Q
What is COPD?
A
- A lung disease characterised by airflow limitation, not fully reversible
- FEV1/FVC ratio less than 70%
- Chronic bronchitis
- Emphysema
2
Q
What is chronic bronchitis?
A
- Disease of mucus blocking the airways
- Productive cough for 3 months in 2 successive years
3
Q
What is emphysema?
A
- Disease of loss of elastic tissue around acini and terminal bronchioles
- Airspaces are enlarged
4
Q
What are the risk factors of COPD?
A
- Smoking
- Age
- Urban environment
- Occupation
- Low birth weight
5
Q
What is the pathogenesis of chronic bronchitis?
A
Irritants induce:
- hypersecretion of mucus + hypertrophy of mucus glands
- metaplasia of ciliated epithelium → squamous epithelium
- CD8+ T-cells, macrophages and neutrophils
6
Q
What is the gross appearance of CB?
A
- Swollen + erythmatous airways
- Covered in layer of mucin
7
Q
What are the hallmarks of CB?
A
- Mucus gland hypertrophy
- Increase in goblet cells
- Loss of ciliated cells
- +/- squamous metaplasia
8
Q
What are the complications of CB?
A
- Severe airway obstruction: hypercapnia, hypoxemia, cyanosis
- pulmonary hypertension → right HF
- recurrent infections
9
Q
What is the respiratory acinus?
A
- Portion of lung tissue formed by branching of a single terminal bronchiole
- Includes respiratory bronchiole, alveolar ducts and alveoli
10
Q
What is a lung lobule?
A
- Hexagonal area of lung parenchyma, consisits of 3-5 respiratory acini
11
Q
What is centriacinar emphysema?
A
- Central/proximal part of acinus affected
- Seen mostly in apical lobes
12
Q
What is panacinar?
A
- Acini uniformly enlarged
- More common in lower lobes
- Occurs in A1AT deficiency
13
Q
What is distal acinar?
A
- Predominantly affects the distal part of acinus
- Mostly associated with pneumothorax
14
Q
What is the pathogenesis of emphysema?
A
- Elastase: protease present in macrophages + neutrophils, released during inflammatory response
- Antiproteases: Alpha 1 antitrypsin (A1AT) counteract elastase effect
- People with deficiency of A1AT have higher incidence of emphysema
15
Q
How does tobbaco affect capillaries?
A
- Nicotine
- IL-8, LTB4, TNF
- Stimulate neutrophils to release elastase