Emphysema Flashcards
What is emphysema?
A breakdown of the collagen and elastase causing alveolar wall destruction.
What structural changes occur in emphysema?
Bullae - permanent air filled spaces (at least 1cm)
Fusion of adjacent alveoli (breakdown of septa).
What is the function of elastase in the lung?
It helps the lung to recoil and keeps strength in the alveolar walls.
What happens when elastase is destroyed?
Exhalation - the walls collapse, trapping air inside the lungs.
Inhalation - the walls expand very easily causing a massive increase in gas inhaled
What is the pathophysiology behind pink puffers?
By pursing their lips, COPD patients manage to increase the pressure inside their lungs.
This allows the alveolar walls to remain open, allowing more air to be exhaled.
What is seen on X-ray of emphysema patients?
Increased anterior-posterior distance
Flattened diaphragm
Increased lucency of lung field
In which conditions are the lungs hyper lucent?
Emphysema
Pneumothorax
Why do emphysema and chronic bronchitis occur together?
They share the same common cause/risk - smoking.
What is the hallmark sign of COPD?
Reduced FEV1:FVC ratio.
How does emphysema affect the total lung capacity?
Increased - more air is taken in (and trapped).
What is the pathophysiology behind smoking and emphysema?
Smoke irritates the lungs - lungs release inflammatory markers - proteases (elastase and colleganase) - destroy elation and collagen.
What are the types of emphysema?
- Centriacinar - most common
- Panacinar
- Paraseptal
What are other signs and symptoms associated with emphysema?
- Weight loss
- Cough (with small amount of sputum - NOT as much as chronic bronchitis)
- Barrel chest
What is centriacinar emphysema?
Central damage affecting the proximal alveolar - because its the first alveoli the smoke can damage.
Affects the upper lobes most.
What is panacinar emphysema?
Affects all of the alveoli
Associated with alpha-1-antitrypsin deficiency.
Mostly affects lower lobes.
