Developmental aspects of lung disease

Question 1

During growth and development of the lung, what processes/systems are needed for healthy lungs?

Answer 1

Morphogenesis
Surfactant system
Postnatal lung growth

Question 2

Abnormalities of growth and development of the lung leads to…

Answer 2

Congenital lung disease

Hyeline membrane disease

Question 3

The stages of lung morphogenisis are?

Answer 3

Embryonic
Pseudo-glandular
Canalicular
Saccular
Alveolar

Question 4

Embryonic stage happens when?

Answer 4

3-8 weeks into gestation

Question 5

Pseudo-glandular stage happens when?

Answer 5

5-17 weeks

Question 6

Canalicular stage happens when?

Answer 6

16-26 weeks

Question 7

Saccular stage happens when?

Answer 7

24-38 weeks

Question 8

Alveolar stage happens when?

Answer 8

36 weeks and continues on for roughly 2 to 3 years

Question 9

In what stage of lung morphogenesis does the larygo-tracheal groove grow forward to form the primitive trachea?

Answer 9

Embryonic

Question 10

Gas exchange becomes possible towards the end of the BLANK stage.

Answer 10

Canalicular

Question 11

What can be seen in the pseudo-glandular stage?

Answer 11

Major airway abnormalities

Small airways

Increased branching

Blood vessels a large distance from airways

Question 12

What happens to the blood vessels in the Canalicular stage?

Answer 12

Move closer to allow gas exchange

Question 13

As the alveolar stage of lung morphogenesis continues, the number of alveoli…

Answer 13

Increases

Question 14

The continuation of alveolar separation in postnatal lung growth allows for…

Answer 14

A larger surface area to allow gas exchange

Question 15

Expansion of air spaces occurs in which stage?

Answer 15

Saccular

Question 16

When is surfactant detectable in amnionic fluid?

Answer 16

Saccular stage - ~24 weeks

Question 17

In the embryonic stage, what structural abnormalities can be seen that point to congenital lung disease?

Answer 17

Stenosis (narrowing) of the tracheal/laryngeal
Pulmonary agenesis
Tracheo-oesophageal fistula

Question 18

What does agenesis mean?

Answer 18

The failure of an organ to develop during embryonic growth due to the absence of primordial tissue.

Question 19

What is a fistula?

Answer 19

An abnormal passage between a hollow or tubular organ and the body surface, or between two hollow or tubular organs.

Question 20

What abnormalities can be seen in the pseudoglandular stage that point to congenital lung disease?

Answer 20

Pulmonary sequestration

Cystic-Adenomatoid malformation

Cyst formation

Question 21

What does congenital mean?

Answer 21

A condition existing at or before birth

Question 22

What is a pulmonary sequestration?

Answer 22

When a piece of lung tissue isn’t attached to the pulmonary arterial blood supply, so isn’t connected to the normal bronchial airway architecture, and fails to contribute to respiration

Question 23

What are the two common diaphragmatic abnormalities?

Answer 23

A diaphragmatic hernia 
A eventration (where most of diaphragm is raised)

Question 24

What functional changes occur in the lungs at birth?

Answer 24

Change from fluid secretion to fluid absorption Pulmonary vasodilatation

Question 25

What can happen in a newborn baby whose lungs haven’t transitioned from fluid secretion to absorption?

Answer 25

Tachypnoea (rapid breathing)

Question 26

Function of surfactant in the lungs?

Answer 26

Stabilises alveoli

Promotes gas exchange

Question 27

What does surfactant deficiency cause?

Answer 27

Neonatal lung disease - hyeline membrane disease

Question 28

Chronic neonatal lung disease is suspected to lead to what diease in children in adult life?

Answer 28

COPD

Question 29

What can lead to adult COPD in the antenatal stage of a childs life?

Answer 29

In utero nicotine exposure Low nutrition
Micronutrients and vitamins
Low birth weight/prematurity

Question 30

What can lead to adult COPD in the post-natal stage of a childs life?

Answer 30

Infection (Barker hypothesis)
Growth
ETS (+/- 1 AT deficiency)
Environmental pollution
Micronutrients/vitamins

x

Question 31

People with normal, healthy lungs will experience decreased lung function when?

Answer 31

With age

Question 32

Accelerated decline in lung function can be seen in what type of patient?

Answer 32

Smokers
Premature babies
Children exposed to second hand smoke Children who have experienced lung insult

Question 33

If long term smokers quit smoking, will there be any effect on their lung function?

Answer 33

Lung function will still decrease faster than that of a non-smoker, but will improve compared to those who keep smoking

Question 34

COPDs main cause is?

Answer 34

Heavy smoking

Question 35

Low lung function at birth increases the risk of developing what?

Answer 35

COPD