EXAM #1: OBSTRUCTIVE DISEASE Flashcards
What is atelectasis?
Incomplete expansion of the lung
What are the four types of atelectasis?
1) Resorption= airway obstruction leading to incomplete expansion
2) Compression= excess matter in lung space preventing expansion
3) Patchy=microatelectasis/ loss of surfactant (post-op)
4) Contraction= fibrosis around the lung preventing full expansion
What is the difference between the direction of medisatinum shift in resorption and compression atelectasis?
Resorption= mediastinal shift TOWARD affected lung
Compression= mediastinal shift AWAY from affected lung
What are the two major types of pulmonary edema?
1) Hemodynamic distrubance
2) Microvascular injury
What is the most common cause of hemodyamic pulmonary edema?
Increased hydrostatic pressure e.g. left-sided CHF
What are heart failure cells?
Hemosiderin-laden macrophages
What is the mechanism of edema caused by microvascular injury?
1) Injury to capillaries in alveolar septa
2) Leakage of fluid and proteins
What is the major difference between restrictive and obstructive lung disease?
Obstructive= can’t get air OUT
Restrictive= can’t get air IN
What are the major obstructive lung diseases?
1) COPD
2) Asthma
3) Bronchiectasis
What happens to FEV1 and FVC in obstructive disease?
- FEV1= decreased b/c difficulty getting air OUT
- FVC= normal or slightly decreased
FEV1/FVC is LOW
What happens to FEV1 and FVC in restrictive disease?
Can’t get air IN, but what you do get in can go OUT
Thus, FVC is low and TLC are low–BUT, FEV1/FVC is normal
When does one see the sx. of emphysema i.e. how bad does the disease have to be for there to be clinical significance?
1/3 of pulmonary capacity impaired
What airways are affected in emphysema?
Airways DISTAL to the terminal bronchiole
Destruction of the airway WITHOUT obvious fibrosis
Describe the pathogenesis of emphysema.
1) Smoking is proinflammatory increase neutrophil recruitment and alveolar macrophage activity
2) Neutrophils/ alveolar macrophages increase elastase/protease secretion that induces tissue damage
3) Furthermore, smoking inhibits antielastase
What cytokines are induced by smoking to attract neutrophils to the lungs?
1) IL-8
2) LTB4
3) TNF
What is the normal alpha-1 antitrypsin phenotype?
PiMM
What is the phenotype associated with severe alpha-1 antitrypsin disease?
PiZZ
What are the different types of emphysema?
1) Centriacinar= center of the acinus
2) Panacinar= entire acinus
3) Paraseptal
4) Irregular
What type of emphysema is most associated with smoking?
Centriacinar
*Inhalation of smoke affects the center of the acinus the most
Where is centriacinar emphysema most severe in the lung?
Apex
*Remember that smoke rises–mnemonic to remember the apex is most affected
What type of emphysema is most assocaited with alpha-1 antitrypsin deficiency?
Panacinar
*Lack of anti-protease causes damage to the entire acinus vs. just the central portion that is most exposed to smoke
What part of the lung is most affected by panacinar emphysema?
Base
What kind of emphysema is associated with bullae and pneumothorax?
Paraseptal/ distal acinar emphysema
What is the surgical procedure that can aid patients with very severe emphysema?
Volume reduction surgery
