Intro Path

Question 1

2 causes of lung hypoplasia (or agenesis).

Answer 1

1. Oligohydramnios

2. Decreased Intrathoracic space (commonly due to space occupying lesion like diaphragmatic hernia)

Question 2

What is a tracheoesophageal fistula?

Answer 2

Communication between esophagus and trachea

Question 3

Cause of a foregut cyst.

Answer 3

Detachment of a fragment of primitive gut that can migrate anywhere.
(in this system we worry about the ones that migrate to the lungs: bronchogenic cysts)

Question 4

What are pulmonary sequestrations?

Answer 4

Presence of a mass of lung tissue without normal connection to the airway system

Question 5

Most common side for extralobar sequestrations.

Answer 5

Left side (90%)
-most associated with other congenital anomalies

Question 6

Major complications of intralobar sequestrations.

Answer 6

Located in the lung tissue and often get infected or cause bronchiectasis (dilation of the bronchial tree due to smooth muscle destruction)

Question 7

What is atelectasis?

Answer 7

Congenital incomplete expansion of a lung
or
Collapse of a previously inflated lung

Question 8

What are the 3 types of atelectasis in non neonates?

Answer 8

1. Resorptive (Obstructive) - most common
2. Compressive
3. Contraction

Question 9

Cause and direction of shift of the mediastinum in resorptive atelectasis.

Answer 9

Caused by complete obstruction of a part of the airway. Mediastinum shifts TOWARD the atelectatic lung.

Question 10

Cause and direction of shift of the mediastinum in compression atelectasis.

Answer 10

Caused by compressive force within the pleural cavity: tumor, fluid, blood, or air.

Mediastinum shifts AWAY from atelectatic lung.

Question 11

Cause of contraction atelectasis.

Answer 11

Fibrotic changes to the lungs or pleura decrease the compliance and prevent full expansion of the lung.

Question 12

Unique characteristic of contraction atelectasis.

Answer 12

IRREVERSIBLE

Question 13

3 classifications of pulmonary edema.

Answer 13

1. Hemodynamic (most common)
2. Microvascular Injury
3. Undetermined Etiology

Question 14

General cause of hydrostatic pulmonary edema.

Answer 14

Increased capillary hydrostatic pressure

• common in left sided heart failure, hypervolemia
• blood/fluid pools in the base of the lungs

Question 15

General cause of microvascular injury pulmonary edema.

Answer 15

Capillary endothelial injury

• infection, toxic gas, drugs, shock, trauma
• protein and fluid leak from capillaries

Question 16

Main two causes of idiopathic pulmonary edema.

Answer 16

1. High Altitude

2. CNS injury

Question 17

How do alveoli appear on histology slide during pulmonary edema?

Answer 17

1. Capillaries dilated
2. If chronic walls thicken
3. Macrophages present (contain hemosiderin due to hemorrhaged or lysed RBCs)

Question 18

What is acute lung injury?

Answer 18

ALI is an abrupt onset of significant hypoxia. If severe enough it can be considered ARDS.

Question 19

What histologic pattern shows up with ALI?

Answer 19

Alveolar wall thickening with dark hyaline cartilage staining preventing diffusion across the respiratory membrane. Termed Diffuse Alveolar Damage (DAD)

Question 20

What is Hamman Rich Syndrome?

Answer 20

Acute Interstitial Pneumonia

• no known cause, however, there are 3 predisposing factors: shock, O2 therapy, sepsis
• often results in non-pulmonary organ dysfunction