______ covers the umbilical cord and merges with fetal skin at umbilicus.
Amnion
Umbilical vein (1) carries ______ blood to fetus from placenta
oxygenated
Umbilical arteries (2) carries ______ blood from fetus to placenta
deoxygenated
The umbilical cord is seen with ultrasound around ___ weeks.
8
The umbilical cord is formed by merger of yolk stalk and _____
allantois
_________ surrounds vessels in umbilical cord
Wharton's jelly
Size of cord (diameter) is variable. Depends on amount of ______
Wharton's jelly
Arteries spiral around the cord. Lack of coiling implies lack of ______________
fetal movement
Cord needs to keep baby off wall of _______, elongates as pregnancy progresses. Average length towards the end of preg is 40-60 cm
uterus
After birth, umbilical arteries become _______ ligaments of bladder. Contain superior vesicle arteries.
Lateral
Umbilical vein heads to fetal liver. Ties into ___ portal vein. Ductus venosus transports most of blood to fetal IVC. Remainder will be used to feed liver.
Left
After birth, umbilical vein becomes _______ or the round ligament
ligamentum teres
A short cord is less than ___ cm. Length of cord believed to be determined by amount of amniotic fluid in 1st and 2nd trimester. Short cord is associated with
-oligohydramnios
-restricted space (multiples)
-fetal anomalies
-tethering of fetus by amniotic bands
-inadequate fetal descent
-cord compression
-fetal distress
35 cm
A long cord is more than ___ cm. Associated with
-polyhydramnios
-nuchal cord
-true knots: vascular compromise
-compression, prolapse, and presentation
-stricture or torsion
80
Cord diameter is variable. Seen with diabetes (____ Wharton's jelly), edema from fetal hydrops, Rh incompatibility, fetal demise
increased
Left twist (upper left to lower right) is preferable. This one is _____
normal
Right twist (upper right to lower left). Associated with _____
fetal anomalies
With ____ of umbilical cord, fetal abd connects directly to placenta. Omphalocele always present
agenesis
Cord ______ are not common. Small cysts may be seen, usually allantois in origin. Usually resolve by end of 1st trimester. If they persist usually associated with anomalies and aneuploidy.
masses
________- failure of intestines to return after 12 weeks. Covered by umbilical cord membrane. Seen in base.
With _______, bowels return to abd normally and end up protruding back out either pre or postnatally. Umbilicus is inadequately closed. Babies with "outies" are more prone to this.
umbilical herniation
With _________ cyst, dilated, residual remnant of a duct. Lined with epithelium of GI origin. Usually found near cord insertion site of baby's abd. May meas up to 6 cm. Associated with Meckel's diverticulum
-outpouching of bowel wall (terminal ileum)
-remnant of fetal yolk stalk
-may mimic appendicitis
omphalomesenteric cyst
________________ of cord arises from cells of the vessels, nodule surrounded by edema, Wharton's jelly disintegrates, size variable, may lead to nonimmune hydrops.
Hemangioma
__________ of cord caused by trauma to cord (cordocentesis), usually occurs near cord insertion of fetal abd, appearance is variable
-early on: anechoic
-later: more echogenic
-complex as liquefies to be absorbed
-anechoic
hematoma
______ of umbilical vessels- blood clot in an umbilical vessel (usually the vein), rate is higher in diabetic mother, may be primary or secondary
-torsion
-knots
-hematoma
-aneurysmal dilation of vessel leading up to clot. Hydrops sets in. Prognosis is poor
thrombosis
____ knots associated with long cords, polyhydramnios, IUGR, and monoamniotic twins. Single or multiples. Caused by dissipation of Wharton's jelly, venous congestion near the knot, thrombus can develop. Use color flow (decreased or absent flow). Assess cord in multiple locations.
true
______ knots- vessels are longer than the cord. They can fold over themselves creating illusion of knot. Flow may appear constricted but will be present
False
_______ cord- most common cord entanglement. During delivery, coils can tighten, fetal heart rate decreases, meconium staining of amniotic fluid (turns white on u/s), placenta may be difficult to visualize.
nuchal
_________ placenta, insertion off to side of placenta. Near os, bad.
Battledore
Membranous/velamentous placenta- exposed ______
vessels
With ________, cord sitting on os. Can hemorrhage
vasa previa
______ of cord, cord is beneath the presenting part. Occurs with abnormal fetal lie (Transverse, breech). Cord becomes compressed during delivery, cutting off blood supply to baby.
prolapse
________ prolapse- cord lies alongside presenting part. Seen with premature labor: baby can be too small to fill pelvis, multiples, obstetric procedures (external version).
occult
_________ is seen frequently in miscarriages and at autopsy. Seen also with marginal or velamentous insertion. Due to atrophy of one artery early in development. Associated with chromosomal abnormality, IUGR (small placenta), congenital anomalies. Congenital anomalies can affect multiple organ systems.
single umbilical artery
_________ umbilical artery- 2 arteries but one is 50% smaller than the other. Smaller artery will be higher resistance (may have no flow at end diastoole). If only one artery present, it will be larger in size.
hypoplastic
_______ of umbilical vein- dilation of umbilical vessels, usually intrabdominally, but extrahepatic. With color flow, it should be seen as continuous with umbilical vein.
Varix
Persistent intrahepatic right portal vein- earlyin development there are 2 umbilical veins. Left goes to left portal vein, right goes to right portal vein. Around ___ weeks gestation, right umbilical vein should regress. Due to issue on left umbilical vein. Associated with congenital anomalies.