Chapter 57: Umbilical Cord (Powerpoint)

vascular connection between the placenta and fetus

umbilical cord

the normal umbilical cord consists of…

two arteries and one vein

normal cord length is ___.

40-60 mm

what surrounds, covers, and protects the umbilical cord?

Wharton’s jelly

how does Wharton’s jelly appear on ultrasound?

hyperechoic

if Wharton’s jelly appears to be too thick, it may be due to…

maternal diabetes, edema secondary to fetal hydrops

how does the umbilical cord appear on ultrasound?

normal twists/coiling

the umbilical vein goes to the ___.

ductus venosus

the ductus venosus becomes the ___ after birth.

ligamentum venosum

where is the ligamentum venosum located?

between the left lobe and caudate lobe

where can you image the 3VC?

in the free floating cord or lateral aspect of the fetal bladder

an abnormally short umbilical cord predisposed to…

oligo, limited space, tethering by amniotic band, inadequate fetal descent, cord compression, fetal distress

a short UC length is related to…

amniotic fluid, oligo, amniotic bands, limited fetal movement

a long umbilical cord is associated with…

poly, nuchal cord, true cord knots, umb. cord compression, prolapse, stricture or torsion

are umbilical cord masses common?

not common

umbilical cord masses are usually…

cysts or an omphalocele

if an umbilical cord mass or cyst persists into the 2nd trimester it could be…

a fetal anomaly

an omphalocele occurs in ___ births.

1 in 5000 births

failure of the intestines to return to the abdomen

omphalocele

if an omphalocele is present, where does the umbilical cord insert?

into the base of the mass

omphalocele is associated with other anomalies, such as ____.

trisomy 13 and 18

trisomy 18 is also called ___.

edward syndrome

right paraumbilical cord defect; bowel loops are not covered

gastroschisis

gastroschisis causes an elevated ___.

AFP

if there is an elevated AFP and nothing wrong with the baby, what should be checked?

placenta

why is there an elevated AFP in cases of gastroschisis?

because the bowel is directly exposed to the amniotic fluid

bowel returns but then herniates pre- or post-natally

umbilical hernia

if there is a hematoma of the umbilical cord, trauma causes blood to seep into ___.

Wharton’s jelly

mass like effect seen within the umbilical cord

hematoma of the umbilical cord

true knots are associated with…

long UC or mono/mono twins

in umbilical cord knots, blood flow changes due to ___.

fetal movement

most common cord entanglement

nuchal cord

nuchal cord usually causes problems when…

the baby begins to descend

prolapse of the cord into the ___ and ___.

cervix and vagina

what are predisposing factors to prolapse of the cord?

abnormal fetal position, nonengagement, long umbilical cord, poly, fibroids, vasa previa, velamentous/marginal CI, incompetent cervix/PROM

atrophy of the umbilical arteries; associated with other anomalies

single umbilical artery/2VC

a 2VC has an increased risk for..

trisomy 13, 18, 21, IUGR, SGA

a 2VC has a high correlation to trisomy __.

21

2VC is associated with ___ and ___.

holoprosencephaly and ventriculomegaly

a normal lateral ventricle should measure ___.

less than 10 mm

dilated umbilical vein, has a swirling color appearance on color doppler

varix of the umbilical vein

the normal umbilical vein courses to the ___.

right (towards the liver)

determining normal UA doppler flow depends on ___.

gestational age

S/D ratio of ___ for an UA doppler is typically a good rule of thumb to go by.

less than 4 cm/s

abnormal UA doppler flow can be ___ or ___.

absent end diastolic flow (AEDF) or reversal flow