Lecture 18 (SMH) Respiratory Distress Syndrome Flashcards
clinical presentation of RDS in neonates:
____ muscle use; ______, ____pnea, retractions, cyanosis
accessory, grunting, tachypnea
Pulmonary surfactant is a mixture of ____ and ____
lecithin, sphingomyelin
when does surfactant synthesis typically begin? When are mature levels typically achieved? What ratio of lecithin to sphingomyelin indicates maturity?
26 weeks, 35 weeks;
2.0
Besides prematurity, 2 risk factors mentioned in FA that increase risk:
mechanism of each:
maternal diabetes. fetal insulin inhibits surfactant production;
C-section: decreased glucocorticoids from fetus = decreased surfactant production
type 2 alveolar cells are present by ___ weeks
20
most important lecithin in surfactant:
phosphatidylcholine
surfactant is synthesied in the ______ of type 2 cells, packaged by the ____, and stored as ____
smooth ER, golgi, lamellar bodies
circulating ____ stimulate surfactant secretion during labor and birth. _____ after birth stimulates further secretion
catecholamines;
lung distension
surfactant reduces ____ by displacing ______ on the alveolar surface
surface tension, water molecules
Law of laplace:
collapsing pressure = (2*surface tension)/radius
are larger or smaller alveoli harder to keep open?
smaller
is respiratory disress syndrome a problem with synthesis or secretion of surfactant?
secretion
RDS is associated with development of ____ membranes due to leakage of ____
hyaline, protein
what does RDS look like on CXR?
alveolar collapse, ground glass appearance of lung fields
treatment:
maternal ____ before birth, _____ for the infant
steroids;
artificial surfactant
