Developmental aspects of lung disease Flashcards
when does embryonic lung morphogenesis take place? is it part of organogenesis or lung differentiation?
3-8 weeks of gestation
when does pseudo-glandular lung morphogenesis take place? is it part of organogenesis or lung differentiation?
5-17 weeks of gestation
when does canalicular lung morphogenesis take place? is it part of organogenesis or lung differentiation?
16-26 weeks of gestation
when does saccular lung morphogenesis take place? is it part of organogenesis or lung differentiation?
24-38 weeks of gestation
when does alveolar lung morphogenesis take place? is it part of organogenesis or lung differentiation?
36 weeks of gestation -2/3 years after birth
what happens during embryonic lung morphogenesis?
formation of major airways (appearance of trachea and main bronchi), formation of bronchial tree and portions of respiratory parenchyma, birth of the acinus (appearance of lung buds), appearance of main pulmonary arteries
what happens during pseudo-glandular lung morphogenesis?
same as embryonic lung morphogenesis + all conducting airways and accompanying blood vessels form, wall structure and epithelial cells differentiate, bronchi 8-13 generation, bronchioli 3-10 generation
what happens during canalicular lung morphogenesis?
last generations of the lung periphery formed (respiratory airways form), epithelial differentiation, air-blood barrier formed and thins, surfactant appears, bronchioli 3-5 generation, alveolar ducts 2-3 generation
what happens during alveolar lung morphogenesis?
secondary septation (cysts are divided in segments)
how do alveoli/airways keep developing after birth? how many are there at birth/ after development?
increased alveolar dimensions, increased alveolar separation (100-150 million at birth to 200-600 million at 3/8 years), airways double in size
when does the embryonic period end and the fetal period starts?
8 weeks
what happens during saccular lung morphogenesis?
expansion of air spaces (= saccules), surfactant detectable in amnionic fluid,
what congenital lung diseases can appear in the embryonic sage of lung morphogenesis?
tracheal stenosis, laryngeal stenosis, pulmonary agenesis, tracheo-oesophageal fistula
what pseudoglandular lung diseases can appear in the embryonic sage of lung morphogenesis?
pulmonary sequestration, cystadenomatoid malformation, cyst formation
diaphragm development- when does the diaphragm close?
about 18 weeks
diaphragm development- which primitive tissues (membranes) combine to form closed diaphragm?
septum transversum (Ant.), mesoesophagus (Post., where everything come through), 2 membrana-pleuro peritonealis (Lat.)
what diaphragmatic abnormalities can take place (before birth?)?
diaphragmatic hernia (L>R, pulmonary hypoplasia (not enough cells), persistent pulmonary hypertension), eventration
at birth, what functional changes occur in the lung?
change from fluid secretion to fluid absorption, pulmonary vasodilation
what composes surfactant?
detergent (phospholipids and lipophilic proteins), SP (surfactant protein) appear 12-14 weeks
what produces surfactant?
type 2 pneumocytes (lamellar bodies)
is surfactant deficiency a prenatal or postnatal lung disease?
postnatal
what is the disease caused by surfactant deficiency called?
hyaline membrane disease (RDS)
how do you treat RDS?
antenatal glucocorticoids, surfactant replacement, oxygen, CPAP (continuous positive airway pressure, no closing of alveoli)), mechanical ventilation
which 2 chronic neonatal lung disease is there?
BPD and CLDP
