Module 8: Fetal GI Flashcards Preview

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Flashcards in Module 8: Fetal GI Deck (61)
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1
Q

What anomalies does cloacal exstrophy include? (4)

A
  • Bladder exstrophy
  • Omphalocele
  • Imperforate anus
  • Spina bifida
2
Q

What fetal assessments are done in the presence of gastroschisis?

A

BPP and non-stress test (NST always done regardless of BPP results).

3
Q

What is body stalk associated with?

A
  • Limb defects (missing limbs or club feet)

- Short or absent cord

4
Q

What is gastroschisis?

A

A defect in the abdominal wall to the right of the umbilical insertion that allows bowel to float freely in the amniotic fluid due to no covering membrane.

5
Q

What type of omphalocele has a higher association of having a chromosomal abnormality?

A

A small omphalocele containing only bowel

6
Q

How do you assess echogenic bowel on US?

A

Turn down gains to see if the bone or bowel disappears first.

If bowel is still visible after bone disappears then it’s echogenic bowel.

7
Q

What is Esophageal Atresia associated with?

A
  • VACTERL
  • Trisomy’s
  • Heart defects
8
Q

How should bowel appear on US inutero?

A

As echogenic as bone.

9
Q

What complications can arise from gastrochisis?

A
  • Small hole can affect blood supply to herniated bowel

- Severe pulling may cause ascites or perforation (leading to meconium peritonitis).

10
Q

What is umbilical vein varix?

A

A dilation of the umbilical vein after it enters the fetal abdomen.

11
Q

What is meconium?

A

Fetal stool

12
Q

What lab value will be increased in the presence of an omphalocele or gastoschisis?

A

MS-AFP

13
Q

Is the fetal colon active inutero?

A

No

14
Q

What is esophageal atresia?

A

Absence of a segment of the esophagus

15
Q

What is an omphalocele?

A

A defect at the base of the cord allowing abd contents to herniate into the umbilical cord.

16
Q

What is echogenic bowel associated with? (4)

A
  • Cystic fibrosis
  • Chromosomal abnormalities
  • TORCH infections from the mother
  • Meconium peritonitis
17
Q

What is the etiology of Esophageal Atresia?

A

Unknown

18
Q

What is a persistent right umbilical vein?

A

During early embryogenesis there are two umbilical veins but only one remains(the left), abnormally the right umbilical vein may persist also.

19
Q

What increases the risk of thrombus in the umbilical vein?

A

Umbilical vein varix

20
Q

What is meconium peritonitis?

A

When a bowel obstruction perforates the bowel wall meconium can leak out and cause peritonitis (infection/inflammation of the peritoneum).

21
Q

What should the small bowel diameter of a term fetus be?

A

Less than 12 mm

22
Q

What should the colon diameter of a term fetus be?

A

Less than 18 mm

23
Q

What is the US appearance of hepatic calcification?

A

Echogenic or hyperechoic focus in the liver that may shadow.

24
Q

What is duodenal atresia?

A

Common small bowel obstruction

25
Q

What is malrotation of bowel?

A

A shortened mesenteric attachments obstructs the duodenal bends causing abnormal rotation and placement of the intestines.

26
Q

What may an Omphalocele contain?

A

Bowel, stomach and liver

27
Q

What Trisomy’s are most commonly associated with omphalocele and what other abnormalities does it appear with?

A

Most common = T18 and T13

Also:

  • T21
  • Turners
  • Triploidy
28
Q

What bowel has peristalsis?

A

Dilated small bowel

(dilated large bowel does not).

29
Q

Why may echogenic debris be seen in the stomach?

A

After amniocentesis, blood in the amniotic cavity may be swallowed by the fetus.

30
Q

What syndromes is gastoschisis associated with?

A

None

31
Q

What can a large omphalocele be associated with?

A
  • Beckwith Wiedemann (over-growth syndrome)
  • Pentalogy of Cantrell
  • Trisomy 18
32
Q

What is the US appearance of duodenal atresia?

A

Two stomachs = Stomach and 1st portion of duodenum

“Double bubble”

33
Q

How does the persistent right umbilical vein travel?

A

Along the right side of the GB and turns toward the stomach instead of away.

34
Q

What may mimic gastrochisis?

A

A ruptured Omphalocele

35
Q

How often is duodenal atresia associated with other anomalies and what are they? (4)

A

50%

  • Trisomy 21
  • Cardiovascular
  • Polyhydramnios
  • Other bowel abnormalities
36
Q

What so higher atresia (high blockages) usually present with?

A

Polyhydramnios

37
Q

What is the cloaca?

A

The rectum and urogenital sinus develop from a primitive structure called the cloaca

38
Q

What is Esophageal Atresia associated with?

A

Tracheoesophageal

fistula

39
Q

What is bladder extrophy caused by?

A

A sporadic defect in the development of cloacal membrane.

40
Q

What is important to document in the presence of an Omphalocele?

A
  • Membrane surrounding contents
  • Cord at centre of mass
  • What organs have herniated
  • Presence of ascites
41
Q

What is meconium ileus?

A

An obstruction of the small bowel with meconium almost exclusively due to cystic fibrosis.

42
Q

What may bladder exstrophy be mistaken for?

A

Omphalocele

43
Q

What is the function of the fetal colon?

A

To collect meconium

44
Q

How does Meconium peritonitis appear on US?

A

Appears as echogenic reflectors throughout the bowel.

45
Q

What is VERY important to be aware of when scanning bowel?

A

A transducer frequency of greater than or equal to 5 mhz will make bowel appear hyperechoic in a normal fetus.

46
Q

What is body stalk anomaly?

A

A fatal abdominal wall defect associated with multiple congenital abnormalities (herniations, ectopic cordis, etc).

47
Q

What increases the risk of gastrochisis?

A
  • Substance abuse
  • Some medications
  • Younger women
  • Smokers
48
Q

What is the US feature of meconium ileus?

A

Echogenic bowel

49
Q

What are the US features of bladder exstrophy? (3)

A
  • Absent bladder with a soft tissue anterior mass
  • Low cord insertion
  • Malformed genitalia
50
Q

Review images

A

….

51
Q

What is the current treatment of gastrochisis?

A

Water bag silo pushes bowel back into abdomen within 72 hrs (no surgery needed).

52
Q

What are the percentages of VACTERL anomalies?

A
  • Vertebral anomalies 60%
  • Anal atresia 60%
  • Cardiac anomalies 60%
  • Tracheoesophageal fistula 85%
  • Renal abnormalities 60%
  • Radial limb anomalies 65%
53
Q

What should be assessed when scanning a fetal abdomen? (7)

A
  • Intact abdominal wall
  • Normal situs
  • Normal cord insertion
  • Skin thickness
  • Fluid collections
  • Appropriate size for dates
  • Bowel echogenicity
54
Q

What are the abdominal contents covered by in an omphalocele?

A

Membrane: peritoneum and amnion

55
Q

What are the common origins of abdominal cysts?

A
  1. Mesenteric or omental
  2. Ovarian
  3. Choledochal cyst on fetal CBD
  4. Hepatic
56
Q

What is another name for body stock anomaly?

A

Limb-body-wall complex

57
Q

Why are fetal assessments performed regularly in the presence of gastrochisis?

A

High still birth rate = 12%

58
Q

What is hepatic calcification due to? (3)

A
  • TORCH (maternal CMV passed onto fetus)
  • Emboli
  • Ichemic damage of liver tissue and necrosis
59
Q

What happens to the fetal gut normally?

A

At 8 weeks it herniates, rotates 90 degrees and returns back to the abdomen by 12 weeks.

60
Q

What is volvulus?

A

When bowel twists around its own blood supply (SMA)

61
Q

What are the US features of Esophageal Atresia?

A
  • Small/absent stomach (depends if fistula is present connecting the esophagus through the trachea)
  • Polyhydramnios
  • Dilated prox esophagus
  • Fetal vomiting