Obstructive lung disease

Question 1

two major causes of airflow obstruction

Answer 1

Intrinsic airway narrowing (bronchospasm, plugging, inflammation/edema) or “Floppy” airways – decreased radial tethering or decreased airway integrity
Intrinsic airway narrowing (bronchospasm, plugging, inflammation/edema) or “Floppy” airways – decreased radial tethering or decreased airway integrity
Intrinsic airway narrowing (bronchospasm, plugging, inflammation/edema) or “Floppy” airways – decreased radial tethering or decreased airway integrity

Question 2

Total work of breathing = ?

Answer 2

work done against resistance to airflow (resistive work)vPLUS work done against the elastic recoil of the respiratory system (elastic work).

Question 3

How do obstructive diseases affect airflow and lung volumes and diaphragm

Answer 3

Airflow is decreased and lung volumes increase (due to incomplete emptying of alveoli causing air trapping). Diaphragm is flattened to allow hyperventilation which then reduces inspiratory pressure and inspiratory capacity

Question 4

What location of airway does bronchitis, asthma, bronchiectasis, bronchiolitis and emphysema affect?

Answer 4

Bronchitis: Bronchi. Asthma and bronchiectasis: bronchi/bronchioles. Bronchiolitis: respiratory bronchioles. Emphysema: alveolar sacs

Question 5

Asthma definition

Answer 5

Asthma is a chronic, reversible inflammatory disorder of the airways associated with airway hyperresponsiveness that leads to recurrent episodes of wheezing, breathlessness, chest tightness, and coughing particularly at night or in the early morning

Question 6

Two types of asthma

Answer 6

Extrinsic (type I hypersensitivity rxn to outside agent) and intrinsic (non immune rxn to aspirin, infection, stress, exercise).

Question 7

Subtypes of extrinsic asthma

Answer 7

atopic or allergic asthma, occupational asthma, and allergic bronchopulmonary aspergillosis.

Question 8

Factors that influence asthma development

Answer 8

–genetic predisposition to atopy or airway hyper responsiveness, obesity, and sex. Exposure to allergens, infection, occupational exposures, smoke, pollution, diet

Question 9

Describe airway inflammation in asthma and cells involved

Answer 9

airway inflammation in asthma is persistent even though symptoms may be intermittent. Involves mast cells (histamine, prostaglandin), Eosinophils, Th2 (cytokine release), dendritic cells, macrophage, neutrophils

Question 10

Structural changes in asthma

Answer 10

Increase in airway smooth muscle cells due to hypertrophy and hyperplasia, Blood vessel proliferation, Mucus hyper-secretion in the context of increased number of goblet cells and increase size of submucosal glands.

Question 11

Key clinical features of asthma

Answer 11

Intermittent (PFTs can be normal btw), reversibility of obstruction, cough, dyspnea, wheezing, exacerbations to exercise, cold air, allergens, nl to increased DLCO

Question 12

Test used to detect asthma

Answer 12

Bronchoprovocation with methacholine (or exercise alone) will show decreased FEV at lower conc than healthy people. The PC20 is the concentration required to lower airflow FEV by 20%

Question 13

Signs of acute asthma

Answer 13

hyperinflation, decreased tension and pressure from diaphragm, Breathing at flatter part of P-V curve so more pressure required to get similar change in volume, accessory muscles, increased work of breathing

Question 14

Asthma severity levels

Answer 14

intermittent (2X/ week), moderate persistent (daily symptoms, multiple exacerbations per week), severe persistent (continual symptoms, frequent exacerbations)

Question 15

Vocal cord dysfunction

Answer 15

•Inappropriate vocal cord adduction during inspiration results in airflow obstruction. Symptoms mimic asthma

Question 16

Stridor

Answer 16

Wheezing sound upon inhalation (seen in vocal cord dysfunction)

Question 17

Vocal cord dysfunction bronchoprovocation

Answer 17

FEV and the 20% change concentration will not change in VCD, but VCD may worsen

Question 18

COPD definition

Answer 18

fixed airflow limitation- includes emphysema and chronic bronchitis

Question 19

Chronic bronchitis defn

Answer 19

•Productive cough at least 3 months over the past 2 years without other cause. Increased airway resistance due to changes in airway structure (edema, mucus, fibrosis). May have overlapping features with asthma. Impaired ventilation

Question 20

chronic bronchitis airways

Answer 20

hypertrophied submucosal glands and increased in number, with increased ratio of glands to bronchial wall thickness. Goblet cells increased in number. Airway lumen is narrowed

Question 21

P-V curve in chronic bronchitis

Answer 21

shifted upwards

Question 22

Chronic bronchitis is a disease of ________________ while emphysema is a disease of _____________________

Answer 22

airways, parenchymal disease (loss of tissue elastic recoil)

Question 23

Emphysema pathogenesis

Answer 23

Loss of normal alveolar spaces with enlargement of distal airspaces. Increased lung compliance (lung is less stiff due to decreased elastic tissue, alpha-1-antitrypsin deficit, apoptosis of alveolar cells, impaired repair). Impaired gas exchange

Question 24

types of distal airspace enlargement in emphysema

Answer 24

pan-acinar involves entire distal airspace (acinus), seen in older patients and alpha1 antitrypsin deficiency. Centri-acinar involves respiratory bronchioles and is smoking related

Question 25

What causes airflow obstruction in emphysema

Answer 25

dynamic airway collapse- loss of elasticity in surrounding tissue of airways

Question 26

P-V curve in emphysema

Answer 26

Curve is steeper and shifted upwards

Question 27

Distinguish chronic bronchitis and emphysema on physical exam

Answer 27

Chronic Bronchitis: Cough, Rhonchi, Wheezing. Emphysema: diminished breath sounds, hyper-resonant. Common: Prolonged expiratory phase, Pursed-lip breathing, Tri-pod position

Question 28

COPD acute exacerbation -signs, precipitated by, treatment

Answer 28

increased cough, Sputum volume and purulence
Increased wheezing. Worsening obstruction on PFTs, Unchanged CXR. Precipitated by infection, pollution, PE, unknown factors. Increased work of breathing due to hyperinflation, increased airway resistance. Treated with bronchodilators, steroids, antibiotics
increased cough, Sputum volume and purulence
Increased wheezing. Worsening obstruction on PFTs, Unchanged CXR. Precipitated by infection, pollution, PE, unknown factors. Increased work of breathing due to hyperinflation, increased airway resistance. Treated with bronchodilators, steroids, antibiotics

Question 29

Causes of death from COPD

Answer 29

Respiratory failure, Right ventricular failure, Pneumonia, Spontaneous pneumothorax, Pulmonary embolism

Question 30

compare DLCO in asthma, chronic bronchitis and emphysema

Answer 30

asthma: nl to increased. Chronic bronchitis: nl to increased. Emphysema: decreased b/c alveolar capillary bed is destroyed

Question 31

Chronic bronchitis and emphysema response to bronchodilators

Answer 31

bronchitis: minimally reversible. Emphysema: not reversible

Question 32

Bronchiectasis

Answer 32

Abnormal Dilation of Proximal Bronchi due to destruction of muscular and elastic components of their walls

Question 33

Presentation of bronchiectasis

Answer 33

cough with purulent sputum (often copious), wheezing, hemoptysis(bronchial arteries enlarge to supply the inflamed airway), mild airflow limitation

Question 34

Pathophys of bronchiectasis

Answer 34

Combo of infectious insult and impaired drainage, obstruction or immunodeficiency. Loss of airway wall integrity with dilation. Recurrent infections worsen bronchiectasis (CF, PCD, immunodeficiency).Dilated, collapsible airways result in obstruction that May be compounded by inflammation

Question 35

Management of bronchiectasis

Answer 35

Airway clearance (promote secretion clearance), antibiotics, treat reactive airway disease

Question 36

Bronchiolitis signs and causes

Answer 36

inspiratory squeaks on exam. Caused by infection (RSV in kids, mycoplasma in adults), toxins, collagen vascular disease, etc