Week 12 - Respiratory System Problems Flashcards
What are the 3 types of respiratory disease?
- obstruction (airway resistance increased, outflow pressure reduced)
- restriction (reduced compliance)
- infection & inflammation
What are some features of Chronic Obstructive Pulmonary Diseases? COPD)
- narrowing of airways - increased airway resistance
- elastic recoil of lungs lost - decreased outflow pressure
- increase in residual volume
Main diseases :
- chronic bronitis (narrowing)
- emphysema (recoil)
What are some features of chronic bronchitis?
- due to smoking or irritants
- causes airway obstruction, shortness of breath, chest pain
How is chronic bronchitis treated?
- stop smoking
- bronchodilators
- antibiotics
How is emphysema caused?
- smoking leads to neutrophils and macrophages releasing elastase
- elastase destroys alveolar walls
- causes emphysema
What are some features of emphysema?
- compliance significantly above normal
- residual volume increased - increased FRC - chronically overinflated lung
- causes shortness of breath, hyperventilation, and expanded chest
How is emphysema treated?
- stop smoking
- supplemental O2
- lung transplant
What are some features of Asthma?
Symptoms
- bronchoconstriction
- oedema of airway mucosa
- mucus secretion
Causes
- air pollution
- genetics
- exercise & cold air
What is the mechanism for asthma?
- mast cells activated
- histamines + cytokines released
- causes oedema, mucus, bronchconstriction from smooth muscle contraction
What is the treatment for asthma?
- bronchodilators
- anti-inflammatories
What are the main disorders within the restrictive lung diseases category?
- Fibrosis - development of excessive connective tissue
- respiratory distress syndrome (IRDS, ARDS, SARS)
What happens as a result of Restrictive lung disease?
- alveolar walls become rigid
Acute disease - sepsis or trauma
- protein exudation
- oedema
Chronic disease - Industrial dust, drugs, rheumatism
- inflammation
- fibrosis
What is the difference between upper and lower respiratory tract infection?
- upper RTI’s are common but minor
- lower RTI’s are rarer but more serious (e.g. bronchitis, pneumonia, tuberculosis)
What are some features of pneumonia?
- caused by bacteria streptococcus pneumoniae, staphlyococcus aureus, or klebsiella pneumoniae
- affects bronchi + alveoli
- causes inflammatory exudate to fill alveoli
- leads to consolidation - lung tissue becomes firm + airless
What are some features of Tuberculosis?
- caused by Mycobacterium tuberculosis (highly contagious)
- 2 phases - latent vs active
Latent - asymptomatic, non-infectious, granuloma in lung tissue
Active (~10%) - spreads to bronchioles + circulation - destroys alveoli
