Resp - Path (Obstructive & Restrictive lung diseases) Flashcards
Pg. 604-605 in First Aid 2014 Sections include: -Obstructive lung diseases -Asthma -Bronchiectasis -Restrictive lung disease
In general, what is the pathogenesis of obstructive lung disease?
Obstruction of air flow resulting in air trapping in the lungs. Airways close prematurely at high lung volumes –> high RV and low FVC. PFTs: very decreased FEV1, decreased FVC –> low FEV1/FVC ratio (hallmark). Chronic, hypoxic pulmonary vasoconstriction can lead to cor pulmonale.
In general, how are lung volumes affected in obstructive lung disease?
Obstruction of air flow resulting in air trapping the lungs. Airways close prematurely at high lung volumes –> high RV and low FVC.
In general, what are the PFT findings associated with obstructive lung disease? Which is its hallmark?
PFTs: very decreased FEV1, decreased FVC –> low FEV1/FVC ratio (hallmark).
What is a complication of obstructive lung disease, and what causes it?
Chronic, hypoxic pulmonary vasoconstriction can lead to cor pulmonale
What are the 2 main forms of COPD? What terms/nicknames help to distinguish them?
(1) Chronic bronchitis - “blue bloater” (2) Emphysema - “pink puffer,” barrel-shaped chest
What type of disease is Chronic bronchitis? What is its pathogenesis?
A form of COPD along with emphysema; Hyperplasia of mucus-secreting glands in the bronchi –> Reid index (thickness of gland layer/total thickness of bronchial wall) > 50%
Describe the cough of patients with Chronic bronchitis.
Productive cough for > 3 months per year (not necessarily consecutive) for > 2 years.
What kind of airways are affected in Chronic bronchitis?
Disease of small airways
What are 5 physical exam findings associated with Chronic bronchitis?
Findings: (1) wheezing (2) crackles (3) cyanosis (early-onset hypoxemia due to shunting) (4) late-onset dyspnea (5) CO2 retention
What is the pathogenesis of Emphysema, and how does it affect the lung’s properties?
Enlargement of air spaces, decreased recoil, increased compliance, low DLCO resulting from destruction of alveolar walls
What are the 2 types of Emphysema? With what is each associated?
Two types: (1) Centriacinar - associated with smoking (2) Panacinar - associated with alpha1-antitrypsin deficiency
How does Emphysema affect compliance, and why?
Increase elastase activity –> loss of elastic fibers –> increased lung compliance
What mechanism is used by Emphysema patients to prevent airway collapse during respiration?
Exhalation through pursed lips to increase airway pressure and prevent airway collapse during respiration
What is asthma, and what effect does it have?
Bronchial hyperresponsiveness causes reversible bronchoconstriction.
What are 3 histological findings associated with asthma?
(1) Smooth muscle hypertrophy (2) Curschmann spirals (shed epithelium forms mucus plugs) (3) Charcot-Leyden crystals (formed from breakdown of eosinophils in sputum)
What are 3 triggers of asthma?
Can be triggered by viral URIs, allergens, and stress
What is the test for asthma?
Test with methacholine challenge
What are 8 physical/lab findings associated with asthma?
Findings: (1) cough (2) wheezing (3) tachypnea (4) dyspnea (5) hypoxemia (6) low I/E ratio (7) pulsus paradoxus (8) mucus plugging
What causes bronchiectasis? What are its 4 main effects?
Chronic necrotizing infection of bronchi –> permanently dilated airways, purulent sputum, recurrent infections, hemoptysis
What are 5 conditions/factors associated with bronchiectasis?
Associated with (1) bronchial obstruction (2) poor ciliary motility (smoking) (3) Kartagener syndrome (4) cystic fibrosis (5) allergic bronchopulmonary aspergillosis
In general, what effect does restrictive lung disease have on lung volumes?
Restricted lung expansion causes decreased lung volumes (decreased FVC and TLC)
What PFT finding is associated with restrictive lung disease?
PFTs: FEV1/FVC ratio >= 80%
What are the 2 major types/mechanisms of Restrictive lung disease? Give a few characteristics that distinguish each of these major types.
(1) Poor breathing mechanics (extrapulmonary, peripheral hypoventilation, normal A-a gradient) (2) Interstitial lung diseases (pulmonary decreased diffusing capacity, increased A-a gradient)
What are 2 ways that poor breathing mechanics can lead to restrictive lung disease? Give 2 specific examples of conditions for each of these ways.
(1) Poor muscular effort - polio, myasthenia gravis (2) Poor structural apparatus - scoliosis, morbid obesity
What are 10 examples of interstitial disease types of restrictive lung disease?
(1) Acute respiratory distress syndrome (ARDS) (2) Neonatal respiratory distress syndrome (hyaline membrane disease) (3) Pneumoconioses (anthracosis, silicosis, asbestosis) (4) Sarcoidosis: bilateral hilar lymphadenopathy, noncaseating granuloma; high ACE and Ca2+ (5) Idiopathic pulmonary fibrosis (repeated cycles of lung injury and wound healing with increased collagen deposition) (6) Goodpasture syndrome (7) Granulomatosis with polyangitis (Wegener) (8) Langerhands cell histiocytosis (eosionophilic granuloma) (9) Hypersensitivity pneumonitis (10) Drug toxicity (bleomycin, busulfan, amiodarone, methotrexate)
What is another name for neonatal respiratory distress syndrome? What type of restrictive lung disease does it cause?
Neonatal respiratory distress syndrome (Hyaline membrane disease); Interstitial lung disease (pulmonary decreased diffusing capacity, increased A-a gradient)
What are 3 examples of Pneumoconioses? What type of restrictive lung disease do they cause?
Pneumoconioses (anthracosis, silicosis, asbestosis); Interstitial lung disease (pulmonary decreased diffusing capacity, increased A-a gradient)
What type of restrictive lung disease does Sarcoidosis cause? What 2 physical/histological findings characterize Sarcoidosis? What are 2 substances that it increases?
Interstitial lung disease (pulmonary decreased diffusing capacity, increased A-a gradient); Sarcoidosis: bilateral hilar lymphadenopathy, noncaseating granuloma; increased ACE and Ca2+
What characterizes idiopathic pulmonary fibrosis? What type of restrictive lung disease does it cause?
Idiopathic pulmonary fibrosis (repeated cycles of lung injury and would healing with high collagen deposition); Interstitial lung disease (pulmonary decreased diffusing capacity, increased A-a gradient)
What type of granuloma is associated with Langerhans cell histiocytosis? What type of restrictive lung disease does it cause?
Langerhans cell histiocytosis (eosionophilic granuloma); Interstitial lung disease (pulmonary decreased diffusing capacity, increased A-a gradient)
What type of restrictive lung disease does drug toxicity cause? Give 4 examples of drugs that have this toxicity.
Interstitial lung disease (pulmonary decreased diffusing capacity, increased A-a gradient); Drug toxicity (bleomycin, busulfan, amiodarone, methotrexate)
