RESPIRATORY: 604 - 605 Flashcards
What is the main problem in obstructive lung disease?
Obstruction of air flow - can’t get air out of the lungs
What happens to the residual volume and forced vital capacity in obstructive lung disease?
RV increases and FVC decreases
What is forced vital capacity (FVC)?
Maximal expiration
What are the significant PFT’s in obstructive lung disease?
Extremely decreased FEV1
Decreased FVC
Decreased FEV1/FVC ratio (hallmark)
V/Q mismatch
Name the major complication in obstructive lung disease.
Chronic, hypoxic pulmonary vasoconstriction can lead to cor pulmonale
What is cor pulmonale?
Enlargement and failure of the right ventricle of the heart as a response to pulmonary hypertension
What are the 4 types of obstructive lung disease?
- Chronic bronchitis
- Emphysema
- Asthma
- Bronchiectasis
Describe the pathophysiology of chronic bronchitis.
Hyperplasia of mucus-secreting glands in the bronchi leads to mucus plugs obstructing the airway
What is the classic description of a patient with chronic bronchitis?
Blue bloater
What clinical findings are associated with chronic bronchitis?
- Productive cough
- Wheezing
- Crackles
- Cyanosis
- Late-onset dyspnea
- CO2 retention
What type of cough is diagnostic for chronic bronchitis?
Productive cough for > 3 months per year (not necessarily consecutive) for > 2 years
Which airways are primarily affected in chronic bronchitis?
Small airways
What is the Reid index?
Thickness of gland layer/total thickness of bronchial wall
What complications are patients with chronic bronchitis at risk for?
Infection and cor pulmonale
What is the Reid index in patients with chronic bronchitis?
> 50%
Describe the pathologic changes in emphysema.
Destruction of alveolar walls leads to enlargement of air spaces, decreased recoil, and increased compliance
Why do emphysema patients exhale through pursed lips?
To increase airway pressure and prevent airway collapse during respiration
What are the two types of emphysema and what are they associated with?
- Centriacinar - smoking
2. Panacinar - alpha1-antitrypsin deficiency
What is chronic bronchitis usually linked to?
Smoking
What are two mechanisms by which emphysema leads to air trapping?
- Loss of elastic recoil and subsequent collapse of small airways
- Imbalance of proteases and antiproteases
Is emphysema more a physical or physiologic obstruction?
Physiologic