Obstructive pulmonary diseases Flashcards
What do obstructive lung diseases cause?
Obstructive lung diseases decrease the flow of air through airways during expiration
What are the obstructive lung diseases?
(1) Asthma
(2) COPD - (a) emphysema and (b) chronic bronchitis
(3) Bronchiectasis
(4) Cystic fibrosis
What is asthma?
(1) Bronchoconstriction
(2) Airway inflammation - narrowing through edema, basement membrane enlargement, mucus production, and vasodilatation
What is the pathogenesis of asthma?
(1) Inflammatory trigger (stimulating TH2 cells) leads to release of leukotrienes, histamine, prostaglandins, interleukins, proteases, and adhesion molecules
(2) Airway narrowing occurs
(3) Symptoms: cough, wheeze, dyspnea
What is the pathophysiology of asthma?
(5)
(1) Smooth muscle hypertrophy
(2) Enlarged basement membrane
(3) Sloughing of ciliated columnar epithelium
(4) Inflammatory infiltrate
(5) Increased mucus production (mucus plugs)
What are the clinical manifestations of asthma?
(6)
(1) Wheezing
(2) Intermittent dyspnea
(3) Cough
(4) Chest tightness
(5) Hyperexpansion of the thorax during exacerbation
(6) Atopic dermatitis, eczema
What are causes of wheezing that are not asthma? Extrathoracic upper airway
(3) Intrathoracic upper airway
(2) Lower airway
(3)
(8 total)
Extrathoracic upper airway:
(1) Hypertrophied tonsils
(2) Laryngeal edema
(3) Bilateral vocal cord paralysis
Intrathoracic upper airway
(4) Tracheal stenosis
(5) Intrathoracic goiter
Lower airway:
(6) COPD
(7) Aspiration
(8) Bronchiectasis
What is peak flow?
The highest flow rate of air through the airway
Decreased in asthmatics with diurnal variation - elevated peak flow in the evening, depressed peak flow in the morning
What does a pulmonary function test show in asthmatics?
Decreased FEV1/FVC ratio
Spirometry graph will show scooped line, indicating decreased airflow during expiration
What are some asthma triggers?
(5)
(1) Cigarette smoke
(2) Pollution
(3) Mites
(4) Pet dander
(5) Stress
How effective is home-based environmental intervention among urban children with asthma?
Somewhat effective - reduction in days with symptoms but still symptomatic
What are two types of asthma treatments?
(1) Relievers - taken as needed for quick relief of symptoms
(2) Controllers - taken on a daily basis to prevent symptoms long-term
What are two types of asthma reliever-type meds?
(2)
(1) Short-acting β2 agonists - fast-acting, can cause tremor and tachycardia, sometimes used with anti-cholinergics
(2) Sub-Q epinephrine
Which patients get controller meds over relievers?
(6)
(1) 2 doses of beta agonist/week
(2) 2 days of symptoms/week
(3) 2 nocturnal awakenings/month
(4) 2 beta agonist canisters/year
(5) two unscheduled visits/year
(6) Two prednisone bursts/year
What are the asthma controller-type meds?
(6)
(1) Inhaled corticosteroids (ICS) - most common
(2) Long-acting β2 agonists (LABAs)
(3) Leukotriene modifiers (LTM)
(4) Anti-IgE therapy
(5) Methylxanthines
(6) Cromolyn/Nedocromil
What are the inhaled steroids used as asthma controllers?
(6)
(1) Budesonide
(2) Ciclesonide
(3) Flunisolide
(4) Fluticasone
(5) Mometasone
(6) Triamcinolone
How do treatments differ for varying levels of asthma severity in adults?
(3)
(1) Mild - low-dose inhaled corticosteroids
(2) Moderate - low/medium-dose inhaled corticosteroids and LABA
(3) Severe - high dose inhaled corticosteroids and LABAs or LTM and/or anti-IgE, oral steroids if needed
What is important about the administration of long-acting β agonists (LABAs)?
Must be administered with corticosteroids or patients will have increased risk of death
What is COPD?
(1) Airflow limitation that is not fully reversible (2) Usually progressive (3) Associated with inflammatory response in the lungs
What is chronic bronchitis?
Chronic productive cough for 3 months in 3 successive years when other causes of chronic cough have been excluded
What is emphysema?
Abnormal permanent enlargement of airspaces distal to the terminal bronchioles
What are the risk factors for COPD?
(1) Exposures: cigarette (a) smoking, (b) pollution, (c) occupational dusts and chemicals (2) Genetic: α1 antitrypsin deficiency
What are the clinical features of COPD?
(1) Occurs typically in smokers (avg 20 pack year history) (2) Gradually progressive dyspnea with exertion (3) Chronic cough, usually productive (4) Wheezing and chest tightness (5) Frequent respiratory infections (6) Extrapulmonary symptoms: osteoporosis, cachexia (body weakness), depression
How do emphysema and chronic bronchitis compare in pathophysiology?
(1) Emphysema: (a) Mildly decreased airflow (b) PaO2 - 65-75 (c) PaCO2 - 35-40 (d) Diffusing capacity decreased (2) Chronic bronchitis (a) Markedly decreased airflow (b) PaO2 - 45-60 (c) PaCO2 - 50-60 (d) Diffusing capacity normal
What is the effect of COPD on lung volumes?
hmm
How does smoking lead to emphysema?
(1) Harmful particles get trapped in alveoli (2) Inflammatory response is triggered (3) Inflammatory chemicals dissolve alveolar septum
What is therapy for COPD?
(1) Smoking cessation (2) Immunizations (3) Relief of symptoms with bronchodilators and anti-inflammatory agents (4) Treatment that improves survival: supplemental O2 to hypoxemic patients and smoking cessation
What is the time delay between smoking and COPD death?
hmm
How can patients stop smoking?
(1) Behavioral interventions (2) Pharmacotherapy (a) nicotine replacement therapy (b) bupropion (c) varenicline
What is the FEV1 in stages I-IV of COPD?
(1) Stage I: FEV1 >80% predicted (2) Stage II: 50%
What is therapy in stages I-IV of COPD?
(1) Stage I: vaccination to reduce risk factors and short-acting bronchodilator as needed (albuterol or ipratropium) (2) Stage II: Add regular treatment with one or more long-acting bronchodilators (3) Stage III: Add inhaled glucocorticosteroids if repeated exacerbations (4) Stage IV: Add long-term O2 as indicated and consider surgical treatments
What improves survival in severe COPD?
Chronic oxygen therapy
What is lung volume reduction surgery?
Surgical procedure in which parts of the lung are resected to reduce hyperinflation
