Stevens- Lung Development

Question 1

normal human development is ____ weeks

Answer 1

38 weeks

Question 2

chance of survival increases with each additional what

Answer 2

week

Question 3

most common cause of death in extremely preterm babies

Answer 3

acute respiratory failure

Question 4

phase of development weeks 1-4

Answer 4

embryonic

Question 5

main events that happen in embryonic phase

Answer 5

primary main bronchi buds form

Question 6

responsible for developing epithelial airway and tubes

Answer 6

endoderm

Question 7

responsible for mesenchyme development

Answer 7

mesoderm

Question 8

5 stages of lung development

Answer 8

embryonic
pseudoglandular
canalicular
saccular
alveolar

Question 9

4-16 weeks

Answer 9

Pseudoglandular stage

Question 10

-bronchioles and terminal bronchioles form
-vascular network in mesenchyme

Answer 10

pseudoglandular stage

Question 11

16-26 weeks

Answer 11

Canalicular stage

Question 12

respiratory bronchioles form
gas exchange can happen at the end of this stage

Answer 12

canalicular stage

Question 13

babies born before saccular stage need what to survive

Answer 13

O2
steroids (to make surfactant)

Question 14

26-36 weeks

Answer 14

Saccular stage

Question 15

terminal sacs
type II cells secrete surfactant

Answer 15

Saccular stage

Question 16

cell that produces surfactant (lowering surface tension)

Answer 16

type II pneumocytes

Question 17

composed of proteins and lipids (DPPC)

Answer 17

surfactant

Question 18

lowers alveolar surface tension
has antimicrobial properties

Answer 18

surfactant

Question 19

too little surfactant can lead to what in infants

Answer 19

respiratory distress syndrome (restrictive physiology)

Question 20

too much surfactant

Answer 20

pulmonary alveolar proteinosis

Question 21

supplement ___ in preterm infants for air breathing life

Answer 21

surfactant

Question 22

36 weeks-8 years

Answer 22

Alveolar stage

Question 23

alveoli increase
type II cell proliferation

Answer 23

Alveolar stage

Question 24

formed by a process known as secondary septation

Answer 24

alveoli

Question 25

2 types of cells (interstitial cells) that play a role in septation

Answer 25

lipid fibroblasts myofibroblasts

Question 26

make lipids for type II cells so they can make surfactant

Answer 26

lipid fibroblast

Question 27

essential for secondary septation (important for increasing surface area for gas exchange)

Answer 27

myofibroblast

Question 28

____develops and aligns with the airways

Answer 28

circulation

Question 29

Rapid expansion of functional circulation beginning in the _____stage; and circulation becomes continuous here

Answer 29

pseudoglandular stage

Question 30

development of lung bud relies on communication of what 2 things

Answer 30

epithelium (airways) and mesenchyme (circulation)

Question 31

fetal O2 is ____ compared to adults

Answer 31

low

Question 32

low fetal oxygen levels (hypoxia) will promote what

Answer 32

lung development

Question 33

Babies born prematurely will be exposed to oxygen supplementation and while its necessary to have the O2 supplementation to meet metabolic demands of the body; the high level of O2 can cause impairment of normal vascular development-----this is seen in _____ due to preterm birth

Answer 33

broncho-alveolar dysplasia (broncho-pulmonary dysplasia---BPD)

Question 34

this is defined as the need for supplemental oxygen beyond 30 days of life

Answer 34

BPD

Question 35

alveolar simplification capillary hypoplasia interstitial cellularity

Answer 35

BPD

Question 36

hypoxia conditions in the fetus contribute to high ________ in utero

Answer 36

pulmonary vascular tone

Question 37

fetal circulation has high ___ and low ___

Answer 37

high resistance low blood flow

Question 38

the reason the blood is shunted in utero

Answer 38

the resistance in the pulmonary circulation is high and the path of least resistance is to shunt blood from pulmonary to systemic circulation (and lungs not developed)

Question 39

_____ ventricle is unusually large in fetus compared to adult

Answer 39

R ventricle

Question 40

____ artery is highly muscularized in fetal circulation compared to adult

Answer 40

pulmonary artery

Question 41

what decreases minutes after birth

Answer 41

pulmonary vascular resistance (and pressure)

Question 42

retention of medial hypertrophy of pulmonary a. can lead to what of neonate

Answer 42

pulmonary HTN