Abdominal Wall Defects
(Omphalocele and Gastroschisis)
Omphalocele and gastroschisis
are congenital defects of an infant’s abdominal wall. In each
the anterior abdomen does not close properly, resulting in organs
that are normally located within the abdominal cavity remaining
outside.
While a baby is going
through early stages of development the intestines grow faster
than the abdominal cavity; they elongate in the umbilical sac,
which remains open through the first 3 months of gestation.
Toward the end of the first trimester, the intestines normally
return into the abdominal cavity and the sac closes, becoming
the umbilical cord. In omphalocele, the sac does not close
completely, resulting in protrusion of part of the liver or
intestines into the open sac. In gastroschisis, the sac closes,
but an opening develops next to the umbilical cord (usually
on the right) and the intestine remains partially outside the
abdomen. The abdominal cavity remains small and underdeveloped.
Omphalocele and gastroschisis
can often be detected with prenatal ultrasound. The ultrasonographer
usually can identify the omphalocele sac covering the intestines.
Omphalocele is frequently associated with other congenital anomalies
and additional information about the heart, kidneys, lungs,
and intestines can often be obtained during the ultrasound examination.
In gastroschisis no sac is present, and intestine can be seen
floating in the amniotic fluid.
In both conditions treatment
is by surgery soon after birth. Gastroschisis requires urgent
surgery since the intestines are outside the abdomen and predisposed
to injury and infection. Babies with an omphalocele may be
managed semi-urgently, taking time to evaluate the infant for
other possible abnormalities. In each condition the initial
goal of surgery is to close the abdomen; however, forcing the
intestines and other organs back into a small abdomen may result
in serious heart and lung problems. Many babies may require
application of an external covering, often referred to as a
"silo" because of its shape. Over a period of days
the intestines can be gently maneuvered back into the gradually
expanding abdomen. In 5-10 days the baby returns to the operating
room where the silo is removed and the abdomen is closed.
Should I have a Caesarian
section?
The presence of gastroschisis
or omphalocele by itself does not necessarily mean that a "C-section"
is necessary. However, there may be other factors that make
a C-section a better choice. This should be discussed with
your perinatologist and your obstetrician.
Where should I deliver?
Since the care of a newborn
with an abdominal wall defect is critical, especially with gastroschisis,
the safest situation is for the baby to be delivered at a tertiary
care center with special obstetrical and neonatal (newborn)
services. Prenatal consultation with a perinatologist and the
pediatric surgeon permits a team to be assembled ahead of time
to ensure optimal care of mother and baby both during and after
delivery.
What will happen when
the baby is born?
A neonatologist (newborn
specialist) examines the baby to assess the defect and look
for associated problems. If respiratory problems are present,
they are addressed first. The baby is warmed and cleansed.
A small tube is passed through the baby’s mouth into the stomach
to keep the intestines from filling up with air and fluid.
If exposed, the intestines are covered and warmed. An intravenous
line is placed to give fluid and antibiotics. The baby is then
transferred to a neonatal intensive care unit (NICU).
What can I expect after
surgery?
In both conditions (but
particularly in gastroschisis) the intestine takes time to begin
to function, often 2-3 weeks or more. Antibiotics will be continued,
and intravenous fluid, protein, and calories are given. Placement
of a long-term intravenous catheter may be required.
Will my child have a
"belly button"?
Most children with gastroschisis
will have a belly button once repaired. Some babies with omphalocele
will not have a natural belly button once the abdomen is closed,
but one may be fashioned by your pediatric surgeon after the
baby has recovered.
What outcome can I expect?
Overall, infants with few
or no associated anomalies usually do well. Problems with the
heart, lungs, kidneys, or possible genetic syndromes, generally
influence the outcome in omphalocele. Babies with gastroschisis
have other abnormalities less often, but twisting of the intestine
before birth can result in loss of portions of the intestine,
resulting in short gut. Strictures and adhesions may be late
consequences of inflammation that occurs when the intestine
is exposed to the amniotic fluid.
For further information
about abdominal wall defects or to schedule an appointment please
contact us by e-mail or call us at 212-305-0678.
