new new TEGENE,JIMMA, ETHIOPIAN CONGENITAL ABDOMINAL WALL DEFECT
1. EMBRYOLOGY OF ABDOMINAL WALL
DEFECT
MODERATOR – DR. GERSAM
(ASSOCIATE PROF. OF PEDIATRIC SURGERY AND CONSULTANT GENERAL AND
PEDIATRIC SURGEON)
PRESENTER – DR. TEGENE .A (GSR1)
1
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Embryology of abdominal wall defect
3. INTRODUCTION …HISTORY
• Newborns with abdominal wall defects were reported since the first
century
• Omphalocele and gastroschisis are the two primary congenital abdominal
wall defects
• Pare provided the first description of an omphalocele in 1634
• The first successful repair of omphalocele was reported by Hey in 1802
• In 1873 Visick described the successful repair of gastroschisis
• Surgical repair of abdominal wall defects has evolved over many years
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Discover animal
ovum, blast cell
,germ layer
Aristotle- The Father of embryology
Karn Ernst - The Father of modern embryology
4. INTRODUCTION
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EMBRYO occur first disk like anteriorly attach with primitive steak
Migration –cephalocaudal and mediolateral
Germ cell layer -
Form
Heart
Form Bladder
Essential component of abdominal wall
embryology
Form Abdominal
wall
Umbilical cord
Allantois
Umbilical cord
Regress caudally (tail bud)
5. INTRODUCTION…
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Formation of body cavity at end 3rd wk –
Intraembryonic mesoderm differentiate in to
1. Paraxial mesoderm – skull & vertebral
2. Intermediate mesoderm –Genito urinary system
3. Lateral plate mesoderm –body cavity
6. INTRODUCTION…
Embryology Of Congenital Abdominal Wall Defect
• At 3rd and 4th week gestation trilaminar embryonic disc
1) Ectoderm – Dorsal layer neural tube form ( Brain & SC)
By neurulation process
2) Endoderm – ventral layer form =>Gut tube
3) Mesoderm – hold two layer together & lateral plate
mesoderm split in to
Visceral (splanchnic) layer - roll ventrally & connected to
gut tube
Parietal (somatic) layer – together to overlying ectoderm
form lateral body wall fold
space b/n called Primitive Body cavity
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7. INTRODUCTION…
Embryology Of Congenital Abdominal Wall Defect
At end of 3rd week of gestation
• Intraembryonic mesoderm differentiate
to
1) Paraxial mesoderm -> skull &
vertebral
2) Intermediate mesoderm ->urogenital
system
3) Lateral plate mesoderm ->body
cavity
• Solid mesoderm –parietal
(extraembryonic mesoderm)
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8. INTRODUCTION…
Embryology Of Congenital Abdominal Wall Defect
At end of 6th week of gestation
• Lateral body wall fold meet in midline
& fuse to close ventral body wall ,close
completely except connecting stalk
(future umbilical cord)
• Gut tube also closed completely except
vitelline (yolk sack)-connect midgut &
yolk sac.
Congenital Abdominal wall defect occur
interrupt process or defect-
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9. CONGENITAL ABDOMINAL WALL DEFECTS
Embryology of abdominal wall defect
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• It is an opening in the abdominal
wall through which abdominal
organs can protrude.
• The two most common abdominal
wall defects are omphalocele
&Gastroschisis
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12. INCIDENCE
Increase in
mother
younger than
1 in 4000 live birth
preterm more than
term ( 28% vs 6% )
Term likely SGA
Male> female
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13. ● During 4th week : Embryonic
folding
EMBRYOLOGY
● 6th week -> rapid intestinal and liver growth -> herniation
of midgut into umbilical cord
● 10th midgut return to abdominal cavity
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14. EMBRYOLOGY
○ Once believe failure of mesoderm to form
ant abd wall
○ Believe in failure of migration
of lateral fold
○ Develop early in gestation before
omphalocele might develop
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Currently, the ventral body folds theory
15. ● Failure of umbilical
coelom to develop
● Elongate intestine has no
space to expand ->
rupture out of body wall
● Rt side of umbilicus is
relatively unsupported due
to resorption of umbilical
vein at 4th weeks gestation
EMBRYOLOGY
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16. ● Bowel usually quite normal at birth
● After expose to air together with
mesenteric venous occlusion ->
edema and transudation of
proteinaceous fluid
● Bowel is usually thickened,
matted, edematous, covered
with fibrous peel
coran
EMBRYOLOGY
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18. PRESENTATION
● Content Only intestinal always no
sac
● Fascial defect right of the
normal umbilicus
● Umbilical cord attached to
umbilicus
● Skin bridge may be present b/n
cord & defect.
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19. COMPLEX AND SIMPLE
GASTROSCHISIS
• Complex gastroschisis
- 7-28% of cases
- One or more of the
following conditions
● Intestinal atresia
● Perforation
● Necrosis
Simple gastroschisis
● Without intestinal
complication
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20. DIAGNOSIS
• Elevated maternal alpha-fetoprotein level
(MSAFP) Significantly -
• Reliable but not specific
• Amniotic fluid AchE
• Diagnosed by 20 week gestation by u/s
• Bowel loop freely floating in amniotic fluid
• Defect in the abdominal wall to the right of normal
umbilical cord
• Prenatal predictor conditions –
• IUGR
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Gastroschisis are fetuses at risk
o Intra-abdominal bowel dilation
o Bowel wall thickening,
o Gastric dilation
o IUGR
o Polyhydramnios
o liver herniation, urinary bladder
herniation, and
o changes
in bowel dilation over the gestation
21. PRENATAL MANAGEMENT
Increased IL-6, IL-8, TNF –alpha
in amniotic fluid
abnormal collagen
disposition
inflammatory
thickening of
visceral bowel wall
“matted “
Intestinal loops
Intestinal dysmotility
& malabsorption
Decrease in interstitial
cell of Cajal
(ICCs)
Duration of amniotic
fluid expose to
bowel
Furosemide
Amniotic fluid
exchange
Lack of protective sac
E f f e ct o
f
fetal urine
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Implicating the role of the proinflammatory state in
utero.
By Induces fetal
22. Optimal Route Of Delivery
• Vaginal delivery -> injury or
increased risk for infection
and sepsis
• Review suggest both vaginal
delivery and C-section are
safe
• C-section reserved for
indication eg. Fetal distress
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23. Optimal time of delivery
exposure of
bowel to
amniotic
fluid
damage
pacemaker cell
and nerve plexus
Dysmotility
and
malabsorpti
on
Preter
m
deliver
y
• Cochrane review 2013,
• There was not enough
evidence to suggest
beneficial effect of preterm
delivery
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24. • Toronto
overlapping
report
• Early delivery
has higher
complication
rate
• Planning
induction at 37
weeks was better
than expectant
management
• Canadian
Pediatric
Surgery
Network
( CAPSNet)
• Longer GA
decrease bowel
matting,
• Strongly
advocated
delivery at 37 week
OPTIMAL TIME OF DELIVERY
• RCT from UK
• No benefit in
early delivery
• Birth weight less
than 2 kg
increase
morbidity
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26. POSTNATAL MANAGEMENT : NEONATAL
RESUSCITATION
• IV access
• Fluid resuscitation and maintenance of
euthermia
• 2-3 times normal
• Isotonic (10% DNS)
• Nasogastric tube
• Decompression of bowel
• ETT -> not necessary in routine
• Bowel protection
• Warm saline-soaked gauze
• Position -> Rt side up prevent kinking of
mesentery -> bowel ischemia
• Viscera -> cover with plastic bag ( bowel bag)
• Significant evaporative
water loss
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27. • Beware of excess fluid
resuscitation is harmful causes
• Edema
• Increase time to closure
• Increase abdominal compartment
syndrome
POSTNATAL MANAGEMENT : NEONATAL
RESUSCITATION
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28. RISK STRATIFICATION
• Some group of gastroschisis
has high risk of morbidity
and mortality
• Based on other complication
• Atresia
• Ischemia
• Perforation
• development of
necrotizing
enterocolitis (NEC)
Gastroschisis with intestinal atresia
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30. Patient with complex defect
require
• Multiple operative
intervention
• Prolong hospitalization
• Rates of sepsis
• Rates of prolonged
cholestasis
Gastroschisis with intestinal perforation
RISK STRATIFICATION
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31. SURGICAL MANAGEMENT
Primary goal
• Return the viscera to the abdominal cavity
• minimizing risk of damage due to intestinal injury or increased intra
abdominal pressure
Options
• Primary repair
• Delayed closure with use of temporary silo and serial reduction
• Bands should be lysed before placing silo or primary closure
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34. INCIDENCE
1 in 1100 at 14-18
week
1 in 4,000-6,000 at
birth
Termination of
omphalocele in
pregnancy were
Incidence and prevalence remain
stable
Associate anomality -50%
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35. ETIOLOGY
• Defect is not from failure in body wall closure or migration
• Failure of viscera to return to the abdominal cavity due
to umbilical cord is attached to the sac
• Defect in FGF, HOX, SHH pathway
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- Potent mitogen for cell .
37. Location : mid-abdominal or
central may occur at epigastric
or hypogastric
covering layer of umbilical
cord, amnion, Wharton jelly,
peritoneum
ETIOLOGY
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38. ETIOLOGY
Epigastric ; Pentalogy of Cantrell, Ectopia cordis thoracis
Hypogastric;- Bladder/Cloacal exstrophy
The heart is outside the chest
with no pericardial covering
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39. ASSOCIATED DEFECT
• Associated defect
• Chromosomal abnormalities
• trisomies 13, 18, 21, 45X
• Nonsyndromic organ system anomalies
• Beckwith-Weideman-hypoglycemia b/c
hyper insulinemia , risk cancer
• Pentalogy of Cantrell
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13- PATAU
SYNDROMES
18-EDWARD SYNDROMES
DS
40. PRENATAL DIAGNOSIS
• Elevation of maternal serum AFP (
not common as in gastroschisis)
• U/S normal by18 week
• Isolated omphalocele survival rate
90%
• With other defect is likely to survive
• U/S + karyotyping
• Identify 60-70% of postnatal
associated defect
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41. • Prenatal screening should evaluate for
• Cardiac anomalies 14-47%
• Central nervous anomalies 3-33%
• Severe defect -> termination of pregnancy
• Predict out come
• O/HC, O/AC have been studies to correlation of postnatal morbidity
and mortality – Increasing Ratio – Indicate poor out come.
• If omphalocele is suspected : amniocentesis, (cvs) chronic villus
sampling should be perform to evaluate ass chromosomal
abnormalities
PRENATAL DIAGNOSIS
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42. OMPHALOCELE
● Liver and bowel can be
herniate
● Sac always present
● Umbilical cord inserts into
sac
● Midline defect
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44. PERINATAL CARE
Route of delivery
• Obstetric consideration
• C-section did not show advantages
• Term and vaginal delivery is preferred
• Giant omphalocele tend to be delivered by C-section (fear of
liver injury )
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45. NEONATAL RESUSCITATION AND
MANAGEMENT
• Search for associated anomalies
• Echocardiogram
• U/S for renal abnormalities
• Blood for glucose , genetic evaluation
• Sac covered with saline soaked gauze and
impervious dressing
• NG tube placed with suction
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46. RISK ASSESSMENT AND STAGING
• Based on presence or absence of anomalies
• Isolated omphalocele have better prognosis
• Based on location on abdomen
• Hypogastric -> ass with cloacal exstrophy
• Central
• Epigastric -> ass cardiac anomalies , and
Pentalogy of Cantrell
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47. • Based on size
• Hernias of cord -> Defect less than 1.5 cm
• Small -> defect 2-3 cm
• Medium
• Large
• Giant -> defect > 5 cm , > 75% of liver in the sac
• Increasing size has worse outcome , but the definition of
exact size is lacking
RISK ASSESSMENT AND STAGING
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50. SUMMARY OF SEMINAR
• Essential component of abdominal wall embryology=
• Embryo first look like Disk & attach anteriorly with primitive
steak –Migration and germ cell layer differentiate –Lateral
migration form abdominal wall
• The Two commonest congenital abdominal wall defect
• Incidence – increasing vs stable, associate anomality
• Diagnosis – MSAFP & U/S
• Out come determined by bowel condition vs associate anomality
• Management –prenatal vs post natal (NBC,RISK.S & Surgical )
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Delivery - Route – Time
–
