omphalocele and gasroschisis

1. CONGENITAL
ABDOMINAL WALL
DEFECTS
By Biruk Ertiban(GSR 3)
Moderator:DrWendwesen(MD,GS,PS)

2. outline
• Introduction
• Embryology of abdominal wall
• Gastrischisis
• Omphalocele
• Procedures
• Summary
• Reference

8. 2nd week

9. 4th week

10. 6th week

11. Obliterated Rt umblical vein

12. EMBRYOLOGYAND ETIOLOGY
Omphalocele
• during the fourth week of gestation
• differential growth of the embryo
• Causes infolding in the craniocaudal and mediolateral
directions.
• During the sixth week, rapid intestinal and liver growth
leads to herniation of the midgut into the umbilical
cord.
• Elongation and rotation of the midgut occurs
over the ensuing four weeks.

13. …cont
• By week 10, the midgut returns to the abdominal cavity
• the first, second,and third portions of the duodenum and
the ascending and descending colon assume their fixed,
retroperitoneal positions

14. …cont
• The current understanding of the etiology for an
omphalocele
• not from a failure in body wall closure or migration
• Rather, since the umbilical cord is attached to the sac,
• omphalocele develops due to a failure of the viscera to
return to the abdominal cavity

15. …cont
• liver, bladder, stomach, ovary, and testis
can also be found in the omphalocele sac
• The sac consists of the covering layers of the umbilical
cord and includes amnion,Wharton’s jelly, and
peritoneum
• location of the defect is in the mid-abdominal or central
region, but may occur in the epigastric or hypogastric
regions as well

16. EMBRYOLOGYAND ETIOLOGY
(Gastroschisis)
• etiology for gastroschisis is less clear
• >>One theory suggests that gastroschisis results from
failure of the mesoderm to form in the anterior
abdominal wall
• >>Currently(most widely accepted), the ventral body folds
theory
• which suggests failure of migration of the lateral folds
(more frequent on the right side),

17. possible
causative factors
• Tobacco
• certain environmental exposures
• lower maternal age
• low socioeconomic status

18. GASTROSCHISIS
• 1 in 4,000 live births
• mothers younger than 21 years
• Preterm delivery (28% Vs 6%)
• maternal serum α-fetoprotein
(AFP) level (elevated in the presence of gastroschisis)
• ACHE

20. Diagnostic US by 20 wks
• bowel loops freely floating in the amniotic fluid
• defect in the abdominal wall to the right of a normal
umbilical cord
• Intrauterine growth retardation (IUGR)

21. ..cont

22. …cont
• Some authors advocate selective preterm delivery
based on the finding of bowel distention and thickening on
prenatal ultrasound
• Bowel dilitation from 7 to 25 mm is associated with fetal
distress and demise

23. …cont
• duration of amniotic fluid exposure is correlated with the
degree of the inflammatory peel and intestinal dysmotility
• bowel atresia is the most common associated
anomaly(6.9–28%)
• cardiac, pulmonary, nervous, musculoskeletal
genitourinary systems, as well as chromosomal
abnormalities

24. Perinatal Care(gastris…)
• both vaginal delivery and C-section are safe
• Preterm delivery is advocated
• dysmotility and malabsorption(Damage to the
pacemaker cells and nerve plexi )
• evidence does not support elective preterm delivery for
gastroschisis

25. Neonatal Resuscitation
and Management
• Appropriate IV access and fluid resuscitation initiated after
birth
• Nasogastric (NG) decompression
• The bowel should be wrapped in warm saline-soaked
gauze and placed in a central position on the abdominal
wall
• positioned on the right side(prevents kinking)

26. ..cont
• The bowel should be wrapped with plastic wrap or the
infant placed partially in a plastic bag
• gastroschisis >>>isolatedanomaly
• intestinal atresia, necrosis, or
perforation>>>complicated
• excess fluid resuscitation >>poor outcome

27. Surgical Management
• goal >>return the viscera to the abdominal cavity
• In minimizing the risk of damage due to
trauma or increased intra-abdominal pressure.
Two most commonly used treatment options
I. silo + serial reductions +delayed closure,
II. primary closure

28. …cont
• N.B>>inspection of the bowel for obstructing bands,
perforation, or atresia>>>> before silo application or
primary closure

29. Primary Closure
• in neonates in whom reduction of the herniated viscera
appears possible>> it has to be done
• Is in the operating room, but some advocates primary
closure at the bedside without general anesthesia
• close the skin only and leave the fascia separated

30. …cont
• Prosthetic options for primary closure
• preservation of the umbilicus has
been shown to lead to an excellent cosmetic
result(against the previous view)
• Intra-abdominal pressure approximated from either the
bladder pressure or stomach pressure

31. …cont
• Pressures >10–15 mmHg >>decreased renal and
intestinal perfusion>> apply silo or patch
• Pressures higher than 20 mmHg can lead to
renal failure and bowel ischemia
• CVP greater than 4 mmHg has been correlated with the
need for silo placement or patch closure
• Splanchnic perfusion pressure at least 44mmHg is
acceptable

32. Staged Closure
• Spring loaded silo>>> made it possible to insert the silo in
the delivery room or at the bedside

33. …cont
• takes 1 to 14 days with the majority being ready within a
week, depending on the condition of the bowel and the
infant

34. …cont
Definitive closure
• Small skin flaps around the fascia
• Closure of the fascia in vertical or horyzontal direction
• Closure of the skin in a transverse direction Vs vertical
direction(keyhole sign)

35. …cont
• purse-string skin closure around the umbilicus
• the umbilical cord is tailored to fill the gastroschisis defect
and is then covered with an adhesive dressing
• Residual ventral hernia rates are reported to be 60–84%

36. Primary vs staged closure
• Avoidance of ischemic injury
• Need for mechanical ventilator
• Early initiation of PO feeding to the foolest
• Oxygen requirement
• Vasopressor requirement
• Effect on UOP

37. CLOSING SKIN ONLY

38. Management of Associated
Intestinal Atresia
• Up to 10% of neonates with gastroschisis have an
associated atresia
• jejunal or ileal
• 5% small bowel atresia 5% and a large bowel atresia IS
2%

39. Management of atresia(gastr..)
Options
• Resection and primary anastomosis + primary closure
• Four to six weeks after the primary closure
• Stoma + primary anastomosis

40. complicated gastroschisis
Gastriscisis plus one of the following
• atresia,
• perforation,
• Necrosis
• Volvulus
Associated with poor prognosis

41. Postoperative Course
• abnormal intestinal motility and nutrient absorption,
gradually improve in most patients
• NGT decompression
• Parenteral nutrition
• Enteral feeding started when the bowel functions(wks)

42. …cont
• Early oral stimulation
• Prokinetic medication
•

43. Long-Term Outcomes
• Long-term outcomes for patients born with gastroschisis
are generally excellent( except complex disease)
• complex gastroschisis took a median of 21 days longer to
reach full enteral feedings

44. Poor prognostic factors(complex disease)
• 21 days longer to reach full enteral feedings,
• had a longer total parenteral nutrition (TPN)
use
• had almost 2 months longer length of hospitalization
twice as likely to develop intestinal failure
six times more likely to develop liver disease

45. …cont
• Intestinal transplantation(last resort)
• NEC (up to 18.5%)
• Most patients have some degree of intestinal nonrotation
• Cryptorchidism(15–30%)
• If the umbilicus is sacrificed ,up to 60% of children report
psychosocial stress

46. OMPHALOCELE
• Prenatal Diagnosis And Management
• Elevation of maternal serum AFP(not as much in
gastrisc…..)
• Dx by 2D US at 18wk
• Dx by 3D US at 1st TM
• The incidence of omphalocele seen at 14–18 weeks is as
high as 1 in 1,100
• incidence at birth drops to 1 in 4,000–6,000
• Implies the hidden fetal death

47. …cont
• isolated omphalocele has a survival rate of over 90%, but
is reduced with other defects
• only 14% of omphaloceles were truly isolated anomalies
• cardiac (14–47% incidence of anomalies)
• central nervous (3–33% anomalies) systems

48. postnatal morbidity and survival
• ratios between the greatest omphalocele diameter
compared to abdominal circumference (O/AC),
• The femur length (O/FL),
• head circumference (O/HC)
• the most useful may be the O/HC

49. Perinatal Care
• C/S Vs SVD

50. Ix
• echocardiographic evaluation.
• Renal abnormalities can be detected
by abdominal ultrasound.
• Neonatal hypoglycemia (Beckwith–
Weidemann syndrome)
• Blood samples for genetic evaluation should be obtained
as well

51. …cont
• Saline soaked gause dressung
• NGT decompression
Ruptured omphalocele
• Prenatally
• during delivery
• postnatally

53. Surgical Management
• Changing rapidly after 1940s
• defining a giant defect is variable as some
surgeons use size alone
• presence or absence of the liver,
• an estimate of the amount of intestinal contents
• others have used a combination of the amount of liver and
intestine in the sac

54. Immediate Primary Closure
• Treatment options in infants with omphalocele depend
• size of the defect
• the baby’s gestational age
• the presence of associated anomalies

55. …cont
• Less than 1.5 cm in diameter are referred to as hernia of
the cord
• repaired shortly after birth without any issues as long as
there are no associated anomalies
• Defects that are still easy to close without much
loss of abdominal domain can also be closed soon after
birth

56. …cont
• Primary closure consists of excision of the sac and
closure of the fascia and skin over the abdominal contents
• omphalomesenteric duct remnant could be found
associated with a small omphalocele

57. …cont
• When dealing with a medium-sized omphalocele, care
must be taken when excising the portion of the sac
covering the liver,
• because the hepatic veins are located
just under the epithelium/sac interface in the midline and
can be injured

58. …connt
• Closing a giant omphalocele immediately after birth is a
controversial issue despite good outcomes are present

62. Staged Neonatal Closure
• Staged closure in the neonatal period involves the use of
different techniques
• classified into methods that utilize the existing amnion sac
with serial inversion
• sac is excised and replaced with mesh and then closed
over time

63. …cont
• Methods involving primary repair with mesh require
removal of the amnion sac with the mesh used to bridge
the fascial gap followed by skin closure
• Vacuum closure>>novel

64. Delayed Staged Closure
• With this method, the omphalocele sac is excised
• Silastic sheeting is sewn to the rectus fascia.
• Alternatively, the silo can be sewn to the full thickness of
the abdominal wall

65. …CONT
• With this method, the omphalocele sac is excised and the
silastic sheeting is sewn to the rectus fascia
• Alternatively, the silo can be sewn to the full thickness of
the abdominal wall

68. …c ont
• the use of preformed spring-loaded
silos is usually unsuccessful in babies with
omphalocele(EASILY DISPLACED)

69. Scarification Treatment
• Nonoperative techniques >>allows an eschar to develop
over the intact amnion sac
• eschar epithelializes over time, leaving
a ventral hernia that will likely require repair later in life
• defect too large to allow for a safe primary repair, or
if the neonate has significant cardiac or respiratory
issues

70. …cont
• mercurochrome,
• Alcohol
• silver nitrate as the eschar-producing agents
• But are toxic and obsolate

71. …cont
• silver sulfadiazine
• povidone-iodine solution
• silver-impregnated dressings
• Neomycin
• polymixin/bacitracin ointments arte used this days
• The eschar and epithelialization may take 4-10 weeks

72. …cont
• eventually require closure of a ventral hernia between 1
and 5 Yrs of age
• By primary fascial closure, autologous repair with
component separation, or mesh repair
• Innoviative methods like use of tissue expanders

73. Postoperative Course
• If primary closure has been accomplished, the majority of
patients will require mechanical ventilation
• Feeding when the bowel is active
• Abcs for 48 hrs
• If a ventral hernia develops, repair may be possible after
age >1yr

74. Primary vs staged closure
• Same stay of hospital
• Primary closure>>>early enteral feeding
• Pressure relaped complications Hepatic
congestion,renal failure,bowel infarction >>are common in
primary closure(12%)
• Skin and fascia dehiscence are common in primary
closure(25%)

75. Giant omphalocele
• 75% or more of the liver in the sac
• Poor prognosis
• More than half of the survivors had associated anomalies,
• more than half had neurodevelopmental disability at 1
year of age
• three fourths had feeding problems

76. Long-Term Outcomes
• gastroesophageal reflux (GERD)(43%)
• pulmonary insufficiency(20%)
• recurrent lung infections or asthma,
• feedingdifficulty with failure to thrive(60% with giant
omphalocele)

77. UMBILICAL HERNIA
• After birth, closure of the umbilical ring is the result of
complex interactions of lateral body wall folding in a
medial direction,
• fusion of the rectus abdominis muscles into the linea alba,
• umbilical orifice contraction which is aided by elastic fibers
from the obliterated umbilical arteries

78. …cont
• Failure of these closure processes results in
umbilical hernia
• The actual fascial defect can range from several
millimeters to 5 cm or more in diameter
• incidence in African-American children from birth to 1-
year-old ranges from 25–58%,
• Caucasian children in the same age group have
an incidence of 2–18.5%

79. treatment
• observe the hernia until ages 3 to 4 years to allow closure
to occur
• spontaneous resolution rates of 83–95% by 6 years of
age
• defects greater than 1.5 cm are unlikely to close
• Incidence of incarceration and strangulation is incidence
of less than 0.2%

80. Operative procedure

81. summary
• Omphalocele and gastrischisis are the commonest
congenital abdominal wall defects
• The diseases do have embryological origin is The current
most accepted theory for omphalocele is failure of the
midgut to return back to the cavity
• And the current accepted theory for occurrence of
gastrischis is a mesothelial failure
• Primary closure or staged closure can be used by using
different criterias for both condition
• Umblical hernias are usually managed conservatively

82. Reference
1. ASCHCRAFT’S PEDIATRIC SURGERY,6TH ED.
2. PEDIATRIC SURGERY(ARNOLD G.CORAN),7TH ED.
3. OPERATIVE PEDIATRIC SURGERY,2ND ED
4. ATLAS OF PEDIATRIC SURGERY,2ND ED
5. UPTODATE 21.2

83. THANKYOU