Crr Week 1: Embryology Of The Respiratory System

Front 1

What is the embryologic origin of the lung?

Back 1

Ventral foregut

Front 2

The primitive lung bud forms from which two embryonic layers?

Back 2

Endoderm and splanchnic mesoderm

Front 3

What is the cause of esophageal atresia?

Back 3

Tracheoesophageal septum is deviated posteriorly.

*Tracheoesophageal fistula occurs concurrently

Front 4

When does the formation of the lung bud begin?

Back 4

At the end of the 4th week of development.

Front 5

The lung bud forms as a caudal extension of which diverticulum?

Back 5

Laryngotracheal diverticulum

Front 6

During which week of development do the secondary bronchi appear?

Back 6

6th week

Front 7

Which secondary bronchi (right or left) consists of 3 lobe?

Back 7

RIGHT
(Superior, middle, and inferior lobes)

*The left secondary bronchi consist of superior and inferior lobes

Front 8

The formation of the tertiary bronchi occurs during which week of development?

Back 8

7th week

Front 9

How many bronchopulmonary segments do the right and left lungs have?

Back 9

Right lung = 10 segmental bronchi

Left lung = 8 - 9 segmental bronchi

Front 10

Which bronchioles subdivide to form terminal sacs?

Back 10

Respiratory bronchioles

Front 11

Which two structures are contained in the pleuropericardial folds?

Back 11

1. Common cardial veins
2. Phrenic N

Front 12

Which membranes separate the pleural and peritoneal cavities?

Back 12

Pleuroperitoneal membranes

Front 13

Which structures do the pleuroperitoneal membranes fuse with?

Back 13

Dorsal mesentary of the esophagus and the septum transversum

Front 14

During which week of development does fetal breathing occur?

Back 14

12 - 14 weeks

Front 15

For proper respiration, which 3 events must occur?

Back 15

1. Vascularization
2. Thin membrane for gas exchange
3. Low surface tension for inflation/deflation

Front 16

:List the 5 stages of lung development.

Back 16

1. Embryonic
2. Pseudoglandular
3. Canalicular
4. Saccular
5. Alveolar

Front 17

Which stage of lung development occurs during the timeline of 26 days to 6 weeks?

Back 17

Embryonic

Front 18

Which stage of lung development occurs during the timeline of 6 weeks to 16 weeks?

Back 18

Pseudoglandular

Front 19

Which stage of lung development occurs during the timeline of 16 to 28 weeks?

Back 19

Canalicular

Front 20

Which stage of lung development occurs during the timeline of 28 to 36 weeks?

Back 20

Saccular

Front 21

Which stage of lung development occurs during the late fetal stage until 8 years of age?

Back 21

Alveolar

Front 22

Differentiation of conducting airway epithelium occurs during which stage of lung development?

Is respiration possible during this stage?

Back 22

Pseudoglandular

*Respiration is not possible

Front 23

Congenital diaphragmatic hernia results in abnormalities during which stage of lung development?

Back 23

Pseudoglandular stage

Front 24

During which stage of lung development do the terminal bronchioles divide into respiratory bronchioles?

Back 24

Canalicular stage

Front 25

During which stage of lung development do respiratory brionchioles divide into terminal sacs (primitive alveoli)?

Back 25

Canalicular stage

Front 26

During which stage of lung development is fetal breathing first detected?

Back 26

Canalicular

Front 27

Initial development of the pulmonary capillary network occurs during which stage of lung development?

Back 27

Canalicular

Front 28

During which stage of lung development does surfactant production begin?

Back 28

Canalicular

Front 29

Hypertrophy of the capillary bed occurs during which stage of lung development?

Back 29

Saccular

Front 30

Multiplication of alveoli and capillaries occurs during which stage of lung development?

Back 30

Alveolar

Front 31

During which weeks of development do surfactant levels reach those necessary for survival?

Back 31

26 - 28 weeks

Front 32

What is the primary cause of respiratory distress sydrome?

Back 32

Deficiency of surfactant
(Occurs in premature infants-- babies born before 28 weeks-- due to undeveloped lungs. Type II pneumocytes have not produced suffience surfactant)

Front 33

How can surfactant production be stimulated prior to birth?

Back 33

Administration of glucocorticoids to mother

Front 34

List some causes of hypoplastic lungs that can lead to RDS.

Back 34

1. Oligohydramnios due to bilateral renal agenesis or urinary tract obstruction
2. Congenital diaphragmatic hernia

Front 35

Congenital diaphragmatic hernias typically occur in which portion of the diaphragm?

Back 35

Always in the dorsal aspect, usually on the left side

Front 36

Closure of the ductus arteriosus is dependent on what 3 factors?

Back 36

1. High oxygen passing through ductus arteriosus
2. Release of bradykinin upon lung expansion
3. Decreased production of PGE1 and PGE2 in region of ductus arteriosus

Front 37

List 3 causes for PDA?

Back 37

1. Premature birth
2. Rubella viral infection during first trimester
3. Associated with other heart defects