NBME 22 Answers : Block 1 : #38 = A newborn born at 26 weeks' gestation has ...

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NBME 22 Answers

nbme22/Block 1/Question#38

A newborn born at 26 weeks' gestation has ...

Dipalmitoyl lecithin

+5 upvote downvote
submitted by atstillisafraud(93),

Premie has no surfactant

Angiotensin II - generated in hypovolemia

Dipalmitoyl lecithin aka dipalmitoylphosphatidylcholine lung surfactant

Phosphatidylinositol 4,5-bisphosphate aka PIP2 Gq receptor pathway

Phosphatidylserine -involved in intrinsic apoptosis when exposed on extracellular surfaces

Sphinogmyelin - composes myelin and also has roles in signal transduction, apoptosis. Lecithin: Sphingomyelin ratio >2 indicates mature fetal lungs.

endochondral1 how are we supposed to know that dipalmitoyl lecithin is the same thing as dipalmitorylphosphatidylcholine +3

qfever FA 2019 page 647 Pulmonary surfactant is a complex mix of lecithins, the most important of which is dipalmitoylphosphatidylcholine (DPPC). Also: Screening tests for fetal lung maturity: lecithin- sphingomyelin (L/S) ratio in amniotic fluid (≥ 2 is healthy; < 1.5 predictive of NRDS) +4

+3 upvote downvote
submitted by adong(28),

literally know every single name they can possibly call this

djtallahassee literally a new name every nbme +3

+1 upvote downvote
submitted by paperbackwriter(12),

I think the reason they are being such little turds and calling it dipalmitoyl lecithin instead of DPPC is because there's a thing called the lecithin-sphingomyelin ratio which needs to be high in order to indicate that the fetal lung has matured. Both lecithin (DPPC) and sphingomyelin are present in fetal lungs, but the amount of lecithin shoots way up towards the end of gestation, raising the L:S and indicating lung maturity.