Pulmonary- Obstructive disease

Question 1

What is COPD?

Answer 1

• Airflow obstruction due to chronic bronchitis or emphysema
• airflow obstruction is generally progressive
• may be accompanied by airway hyper-reactivity
• may be partially reversible in asthma, but NOT in progressive COPD
• Obstruction is worse on expiration

Question 2

What are the common obstructive disorders?

Signs and symptoms?

Answer 2

• common disorders:
  
  • asthma
  • emphysema
  • chronic bronchitis
• Signs/Symptoms
  
  • Dyspnea
  • wheezing

Question 3

What is Asthma?

Answer 3

• Chronic inflammatory disorder of the airways
• The inflammation causes:
  
  • recurrent episodes of wheezing
  • breathlessness
  • chest tightness, cough (especially at night an in early morning)
  • hyper-responsive to stimuli
• Widespread but variable obstruction that is often reversible
• **A. normal, B. emphysema, C. bronchitis, D. Asthma

Question 4

Asthma is an atopic disorder. What does this mean?

Answer 4

• Atopy- a genetic predisposition for the development of an IgE mediated response to common aeroallergens
• This is the strongest identifiable predisposing factor for developing asthma

Question 5

What are some stimuli that provoke asthma?

Answer 5

Question 6

What are the risk factors for asthma?

Answer 6

• Atopy
  
  • increased serum IgE
• Family history of allergic diseases
• maternal smoking during pregnancy
• viral infections
  
  • especially RSV and rhino as an infant

Question 7

How is Asthma diagnosed?

What are the differences in severity?

What dictates how the asthma is managed?

Answer 7

• Diagnosis based on flow-volume curves
• FEV₁ and FEV₁/FVC ratio decreased
• Management dictated by FEV₁

Question 8

What is the pathophysiology of Asthma?

(chart)

Answer 8

Question 9

What are the characteristics of COPD?

Answer 9

• deterioration in elasticity or recoil which normally maintains the airways in open position
• decreased rigidity of bronchiolar wall
  
  • collapse during exhalation
• Increase in gas flow velocity in the narrowed bronchioli, which lowers the pressure inside the bronchioli and favors collapse
• Increased secretions that cause bronchospasm
• destruction of lung parenchyma, causing enlarged air sacs and developing into emphysema
• **A. normal, B. emphysema, C. bronchitis, D. Asthma

Question 10

What are the risk factors of COPD

Answer 10

• Cigarette smoking
• passive smoking- increases airway reactivity
• chronic infections
• occupational factors
  
  • coal mining, textile factories, dentists?
• Genetic
  
  • Alpha-1-antitrypsin deficiency
  • only known genetic abnormality that leads to COPD
    
    • Accounts for less than 1% of cases

Question 11

What causes air trapping?

Answer 11

• During inspiration the airways are pulled open so air is able to enter
• Upon expiration, due to loss of recoil in the airways, they will collapse and prevent normal expiratory flow

Question 12

How is COPD diagnosed?

Answer 12

• Chronic productive cough
• airflow obstruction
• pulmonary function tests
  
  • FEV₁/FVC ratio decreased
  • significant decrease in FEF 25-75%

Question 13

How do the lung volumes compare between a person with COPD and a person with healthy lungs?

Answer 13

• COPD
  
  • Larger total lung capacity (TLC)
  • Larger residual volume (RV) because they cannot get as much air out of their lungs
  • decreased expiratory reserve volume (ERV)

Question 14

How is COPD staged?

Answer 14

• **All stages have FEV₁:FEV ratio <70%
• 0: At risk
  
  • normal spirometry but chronic cough or sputum
• 1: Mild COPD
  
  • FEV₁ >80%
• 2: Moderate COPD
  
  • 50% 1 <80%
• 3: Severe COPD
  
  • 30% < FEV₁ <50%
• 4: Very severe COPD
  
  • FEV₁ < 30%

Question 15

What is chronic bronchitis?

Answer 15

• Hypersecretion of mucus and chronic productive cough that lasts for at least 3 months of the year and for at least 2 consecutive years
• inspired irritants increase mucus production as well as the size and number of mucus glands
• mucus is thicker than normal

Question 16

What is emphysema?

What are the different classifications of emphysema?

Answer 16

• abnormal permanent enlargement of the gas exchange airways with destruction of alveolar walls but no obvious fibrosis
• loss of elastic recoil
• Classifications
  
  • Centriacinar- dilation initially affects the respiratory bronchioles
  • Panacinar- dilation initially affects the alveolus and alveolar duct

Question 17

What is the difference between pure chronic bronchitis and pure emphysema?

(pic)

Answer 17

Question 18

What do anti-proteases do?

Answer 18

• Antiproteases prevent the breakdown of tissue proteins
• alpha1- anti-trypsin deficiency is a genetic disorder where the person doesnt have the anti-proteases so their tissue proteins get broken down faster than normal

Question 19

How does smoking cause emphysema?

Answer 19

• Tobacco introduces free radicals into lungs
• the free radicals inactivate the antiproteases
  
  • causing a “functional” alpha-1 antitrypsin deficiency
• This increases neutrophil response and neutrophil elastase
  
  • neutrophil and macrophage elastases cause damage to the tissue

Question 20

What is the pathophysiology of COPD?

(Chart)

Answer 20

Question 21

What is absorption atelectasis?

Answer 21

• Caused when inhaled volumes are not big enough to open the pores of kohn
  
  • make sure TV is set large enough
  • encourage post op deep breathing

Question 22

What is Bronchiectasis?

How is it diagnosed?

Answer 22

• Localized irreversible dilation of the bronchus caused by bacterial infections (air polutants too?)
• Destroys airways leading to airway collapse, airflow obstruction, and inability to clear secretions
  
  • pooling mucus
  • bacterial superinfection is tough to eradicate
• Diagnosis-
  
  • chronic purulent cough
  • clubbing of fingers (not characteristic of COPD)
  • hemoptysis
  • dyspnea/wheezing

Question 23

What is cystic fibrosis?

Answer 23

• Caused by mutation in a single gene on chromosome 7
  
  • with this mutation, they lack a protein that helps move Na and H2O in and out of cells (Cl- is affected too)
• Decreased Cl- transport results in
  
  • results in an abnormally thick mucus outside of epithelial cells
  • destruction and scarring of various glands and tissues, causing damage to lungs, pancreas, liver, GI, & reproductive organs
• Primary cause of M&M of pts with CF is chronic pulmonary infection

Question 24

How id CF diagnosed?

Answer 24

• diagnosed by sweat Cl higher than 70 mEq/L