M8: Fetal GI Flashcards
define anasarca
skin edema, sign of hydrops
the most sensitive measurement for growth of the fetus
AC
when doing an AC, where should the spine be on the screen
L or R,
anterior the spine shadows, posterior its hard to get the landmarks
of umbilical Artery and Vein
Artery: 2
Vain: 1
describe physiological norm gut herniation
occurs @ 8 wks… gut herniates out of the abdo and rotates 90 degrees, returns back to the abdo by ~12 wks
define an omphalocele
does it contain membranes
a defect at the base of the cord, causes abdo contents to herniate into the umbilical cord
yes, contents are covered by membranes - peritoneum and amnion
an omphalocele can contain which organs
bowel, stomach, liver
which lab value is increased w/ omphalocele
MS AFP
which type of omphalocele has a higher association w/ chromo abnormalities
small, containing bowel only
a large omphalocele is associated w/ which conditions
beckwith weidemann
pentalogy of cantrell
T18
or can be isolated
prognosis of omphalocele
depends on associated anomalies
which chromo abnormalities are most commonly associated w/ omphalocele
others
T18, T13
they can also occur w/ T21, Turners (45XO), triploidy
US investigation of omphalocele, what do we need to determine
- if there is a surrounding membrane
- if the cord is at the center of the abdo
- contents of the omphalocele/which organs
- if theres any ascities
- other anomalies
if a fetus has an omphalocele, how do we measure the AC
w/ omphalocele, which landmark cant we get for our AC
dont include the omphalocele in the measurement
umbilical vein going into portal vein
what does the presence of ascities indicate
fetus is going into failure
describe gastroschisis
does it contain membranes
a defect in the abdo wall to the RIGHT of the cord insertion, bowel is seen freely floating in the amniotic fluid
no membranes
is gastroschisis associated w/ other syndromes
not usually
which lab value is increased w/ gastroschisis
MS AFP
risk factors for gastroschisis
substance abuse
some medications
young maternal age
smokers
which abdo wall defect has a high still birth rate
gastroschisis
which fetal assessments are performed regularly if the fetus has gastroschisis
BPP and NST, regardless of BPP results
can the abdo wall defect that causes a gastroschisis affect blood supply to the herniated organs
yes
severe pulling of a gastroschisis can have what complications
ascities or perforation which can lead to meconium peritonitis
a ruptured omphalocele can mimic which other abdo wall pathology
What should you measure with a gastroschisis?
gastroschisis
Bowel wall diameter
describe a body stalk anomaly
an abnormality containing 2 of 3 anomalies:
myelomeningocele or caudal regression
thoracoabdominoschisis or abdominoschisis
limb defects
another name for body stalk anomaly
limb-body-wall complex
US appearance of body stalk anomaly
ectopic cordis or cardiac defects
facial clefts
low fluid
cord short or absent (most important)
describe a bladder exstrophy
what causes it
failure of closure of the bladder, lower urinary tract, symphysis pubis, rectus muscles and skin
defect in development of cloacal membrane
which lab value is increased w/ bladder exstrophy
MSAFP
US appearance of bladder exstrophy
absent bladder w/ soft tissue mass anteriorly (important)
low umbilical cord insertion
malformed genitals
a bladder exstrophy can be mistaken for which other abdo wall abnormality
omphalocele
describe cloacal exstrophy
syndrome that includes bladder exstrophy omphalocele imperforate anus spinal bifida
the rectum and urogenical sinus develops from whic primitive strucutre
cloaca
describe a duodenal atresia
US appearance
a common sm bowel obstruction
2 stomachs (stomach and duodenum) - double bubble sign polyhydramnios
what % of duodenal atresia is associated w/ other anomalies
what are those anomalies
50%
cardiovascular abnorm
T21
bowel anomalies
do low GI obstructions typically cause polyhydramnios
no, colon is not active, only collecting meconium
easy way to tell the sm and lrg bowel apart
sm bowel will peristalsis, larg wont
norm colon diameter of fetus at term
sm bowel diameter
colon: <18 mm
sm b: <12 mm
define volvulus
bowel twisting on its own blood supply
describe a meconium ileus
Us appearance
sm bowel obstruction that occurs almost exclusively w/ cystic fibrosis
echogenic bowel
how to assess echogenity of bowel
split screen, one w/ bone, one w/ echogenic bowl… turns the gains down until bone goes away.
if the bowel is still present than its echogenic.
when scanning for echogenic bowel, what probe frequency must we use
Less than or = to 5 MHz, if over this all bowel will look echogenic
echogenic bowel is associated w/ which abnormalities
cystic fibrosis
choromo abnormalities
TORCH infection
meconium peritonitis
describe meconium peritonitis
a bowel obstruction that can lead to perforation of bowel, leaking meconium into the peritoneum… cause inflammation of the peritoneum
US appearance of meconium peritonitis
echogenic reflectors in bowel
describe an umbilical vein varix
increases risk for what
dilation of umbilical vein after it enters the fetal abdo
thrombus in umbilical vein
what is a persistent umbilical vein
when the R umbilical vein formed during embryogenesis doesn’t disappear and instead travels along the right side of the GB wall and turns towards the stomach
3 causes of hepatic calcifications
TORCH
Emboli
Ischemic damage of liver tissue and necrosis
US appearance of hepatic calcification
Echogenic or hyper focus that may have shadowing
W/ an abdo cyst what is important to determine
Origin
Why is echogenic debris sometimes seen in the stomach
Often idiopathic and not concerning
Can be seen after amniocentesis if so blood leaked into the amniotic fluid and is swallowed by the fetus
Or w/ intrauterine bleeding
