1st Walter

Question 1

Obstructive Lung Diseases

Answer 1

• Decrease flow through airways during expiration
  
  • due to increased resistance
  • SCALLOPING
• Decrease:
  
  • FEV₁/FVC
  • FEV₁
  • FEF_25-75
• affects 15%. of population
• Tests: Forced expiration
  
  • asthma and COPD
• Diseases:
  
  • Asthma
    
    • reversible airway obstruction
    • Beta-agonist=Shift right
      
      • improves FEV₁
  • COPD
    
    • Chronic Bronchitis
    • Emphysema (Also diffusion abnormality)
  • Bronchiectasis
  • Cystic Fibrosis

Question 2

Restrictive Lung Disease

Answer 2

• Decreased volume of air that alveoli can hold
• reduced volumes:
  
  • RV, FVC, FRC, TLC
  • Reduced FVC, but NORMAL OR HIGH FEV₁/FVC
• effects 5.5% of population
• Diseases: PAINT
  
  • Pulmonary Fibrosis
  • ARDS (edema)
  • MS
  • ALS
  • Obesity
  • Scoliosis
• Tests: For volume and capacities
  
  • spiromtry
  • gas dilution
  • Plethysmography

Question 3

What do restrictive and Obstructive lung diseases have in common?

Answer 3

• Both decrease:
  
  • peak airflow
  • FEV₁
  • FVC

Question 4

Tests: Diffusion Abnormalities

Answer 4

• gas transfer from alveoli to pulmonary capillaries
• Edema
  
  • restrictive
• Emphysema
  
  • obstructive

Question 5

Other types of obstruction

Answer 5

• Variable Intrathoracic Obstruction
• Variable Extrathoracic Obstruction
• Fixed Large Airway Obstruction

Question 6

Variable Intrathoracic Obstruction

Answer 6

• Most severe during expiration (Trachea)
  
  • Positive Pleural (thoracic) pressure causes partial obstruction of bronchi
  • Flatten expiratory part of F/V loop
• Relieved during inspiration
• Ex:
  
  • Emphysema
  • asthma
  • Chronic Bronchitis

Question 7

Variable Extrathoracic Obstruction

Answer 7

• Increased during Inspiration
  
  • Partial obstruction due to atmospheric pressure compresing the trachea below site of obstruction
  • Air can’t get in
  • Flattened Inspiratory part of F/V loop
• Expiration:
  
  • might be lower due to reduced inspiratory volume
  • normal shape
• Ex:
  
  • vocal cord paralysis
  • Extrathoracic goiter
  • Laryngeal tumors

Question 8

Fixed Large Airway Obstruction

Answer 8

• Either intrathoracic or extrathoracic obstruction
• Affects both inhale and exhale
  
  • air can’t get in or out
  • F/V loop flattened during inspiraiton and expiration
• Fixed=obstruction doesn’t change during inhale or exhale
• Ex:
  
  • tracheal stenosis caused by intubation
  • Circular tracheal tumor

Question 9

PAINT

Answer 9

Restrictive lung diseases

• Pleural Space disease
• Alveolar Filling processes
• Interstitial Lung Disease
• Neuromuscular Weakness
• Thoracic Cage Abnormalities

Question 10

FEV₁

Answer 10

• Forced Expiratory Volume in 1 second
• Estimates airflow through large airways
• dependent on effort

Question 11

FEF_25-75

Answer 11

• Forced Expiratory flow between 25-75% FVC
• measures smaller airways
  
  • bronchioles
• Independent of effert
• related to intrinsic recoil and dynamic compression