Questions and CORRECT Answers
How many stages of lung development are there? - CORRECT ANSWER - 5 stages
what happens in the embryonic stage of lung development (4-7 weeks)? - CORRECT
ANSWER - lung bud differentiation
trachea and bronchi
pulmonary vein and artery
what happens in the pseudoglandular stage of lung development (7-17 weeks)? - CORRECT
ANSWER - conducting airways
terminal bronchioles
immature neural networks
pre-acinar blood vessels
what happens in the canalicular stage of lung development (17-26 weeks)? - CORRECT
ANSWER - primitive alveoli
type II cells
surfactant synthesis
what happens in the saccular stage of lung development (27-36 weeks)? - CORRECT
ANSWER - alveoli saccules
extracellular matrix
neural network maturation
what happens in the alveolar stage of lung development (36 weeks-2 years)? - CORRECT
ANSWER - expansion of gas exchange areas, nerves and capillaries
, what does fetal lung fluid do? - CORRECT ANSWER - distends the alveoli, gives
configuration to the chest, and contains SURFACTANT (later in gestation)
prior to a spontaneous TERM delivery, what happens to the fetal lung fluid? - CORRECT
ANSWER - production of the fluid is stopped and the fluid is moved into circulation,
capillaries, and to the interstitial and lymphatic system areas
ONLY A SMALL AMOUNT OF FETAL LUNG FLUID IS EXPELLED VIA THE AIRWAYS
IN A NORMAL TERM SPONTANEOUS VAGINAL BIRTH
adaptation to extrauterine life (respiratory) - CORRECT ANSWER - -decrease in PVR
with an increase in pulmonary blood flow
-increase in pulmonary perfusion and oxygenation
-transition of O2 and CO2 exchange to the lungs
-fetal shunts through the ductus arteriosus and foramen ovale gradually close
antenatal steroids (dexamethasone or betamethasone) - CORRECT ANSWER - 24.0 to
33.6 at risk of delivery within 7 days should receive a single course
Repeat course for <34 weeks if it has been >7-14 days since last dose and infant is at risk for
delivery within 7 days
Betamethasone at 34-36.6 weeks if never received steroids
what do antenatal steroids do? - CORRECT ANSWER - They help with fetal lung
development and prevent RDS
Antenatal administration of corticosteroids accelerate lung maturation. The normal thinning of
the double capillary loops, to form the thin gas exchanging walls of alveoli, is accelerated,
resulting in fast alveolisation. The maturation of surfactant producing type II pneumocytes is also
sped up
apnea of prematurity overview - CORRECT ANSWER - -cessation of respirations for at
least 20 seconds (or less if accompanied by cyanosis, pallor, bradycardia, and/or hypotonia)
-common in preemies
-appears in 1st week of life