Pathophys of Chronic Airflow Obstruction Flashcards
4 chronic obstructive airway diseases
Asthma
COPD
Bronchiectasis
Bronchiolitis
Difference between bronchus and bronchiole
Bronchus has cartilage
Bronchiole does not
4 general symptoms of chronic obstructive airway diseases
Cough
Sputum
Dyspnea
Wheeze
Cough reflex
Afferent: stimulation of irritant receptors in airway
Efferent: activation of inspiratory muscles (including diaphragm)
Activation of expiratory muscles and the larynx
Sputum definition
A mixture of saliva, airway lining mucus, and pus that is expelled during coughing
Phlegm is airway mucus
2 sources of mucus
Goblet cells
Bronchial mucus gland
Both increase in obstructive lung diseases
3 general causes of dyspnea in obstructive lung diseases
Increases work of breathing due to increased airway resistance
Hypoxemia
Hyperinflation
5 ways you can get increased airway resistance
Smooth muscle contraction Wall thickening Lumenal occlusion Decreased lung elasticity Obliteration
Obliteration
Inflammation-induced proteolytic damage to the CT framework of the lung and death of alveolar epithelial cells
Can occur in COPD, bronchiectasis, and bronchiolitis
Inflammatory triggers for
- Asthma
- COPD
- Bronchiectasis
- Bronchiolitis
- Primarily allergen driven Th2 response (but also viruses and pollutants)
- Cigarette and biomass smoke (oxidant damage)
- Bacteria
- Various (inhaled fumes, immune rejection, etc)
5 histological features of asthma
Mucus plug containing inflammatory and desquamated epithelial cells Smooth muscle hypertrophy/hyperplasia Thickened basement membrane Goblet cell metaplasia Inflammatory cell infiltration
Emphysema
Proteolytic destruction of alveolar walls
Decreased surface area for gas exchange
Loss of lung elasticity
2 types of emphysema
Centriacinar
Panacinar
Bronchiectasis definition
Irreversible dilation of the bronchial tree
Obliteration of peripheral small airways
Repetitive or persistent infection of proximal airways
Causes of bronchiectasis
CF Ciliary dysfunction syndromes Foreign bodies Tracheomalacia Inhalation of noxious fumes/gases Infection