Flashcards in Lecture 18 - Lung Development and Surfactant Deck (15):
Embryonic period events?
Day 26 - wk7: ventral outpouching, series of branching forming lung bud up to segmental bronchi
Embryonic period risks?
Pseudoglandular Period Events?
5-17wk: continues branching up to terminal bronchioles
Canalicular period events?
16-25wk: alveolar duct formation,
Saccular Period Events?
24wk-postnatal: type II alveolar cells formed and produce surfactant
Late fetal -> 8yr: alveolar maturation and lining formation
Hydrophilic surfactant proteins?
SP-A (reduce surface tension) and D: synthesis and host defence
Hydrophobic surfactant proteins?
SP-B (myelin formation) and C: formation and stabiliation of the phospholipid monolayer
Phospholipid monolayer formation?
lamellar body degraded into tubular myelin by SPA SPA and Ca, SPA B and C form layer
Cells moderating phospholipid turnover?
type II cells, extracellular enzymes, macrophages
degree to which lung will distend per unit chang in pressure (change in V/ Palv-Pip)
Factors afecting compliance?
elasticity of lung tissue, surface tension of air liquid interface at alveoli
Law of Laplace?
r's are equal in sphere, therefor P=2T/r
surfactant reduces tendency for fluid to be sucked into airspace