ABDOMINAL WALL DEFETCTSCONGENITAL UMBILICAL HERNIA

Definition-Fascial defect at the umbilicus is frequently present in the newborn, particularly in premature infants.

Pathology-The defect may have invagination of the intestines or omentum with an overlying skin covering-Its size may actually increase with increase in intra-abdominal pressure.-Protrusion of bowel through the umbilical defect rarely results in incarceration in childhood-most dangerous defects are less than 2cm.

Etiology-Unknown

Incidence-Incidence thus decreases with age as the natural tendency is to close spontaneously.-Is very common 1;1000 -Majority .50 % are small defects less than 1cm in size-belly button umbilical hernia in those < 2years.

Race-The incidence is highest in blacks.

Clinical presentation-Most asymptomatic.-Omentum trapped in the hernia causes reflex vomiting without intestinal obstruction.-Classical presentation is reducing mass in the umbilical area with or without vomiting associated with intermittent abdominal pain.-the hernia may become obstructed, strangulated and present as acute abdomen.

Course- In most children, the umbilical ring progressively diminishes in size and eventually closes. - -Fascial defects less than 1 cm in diameter close spontaneously by 5 years of age in 95% of cases. -When the fascial defect is greater than 1.5 cm in diameter, it seldom closes spontaneously.-Surgical repair is indicated when

1) The intestine becomes incarcerated2) Symptomatic hernia.3) when the fascial defect is greater than 1 cm, in girls over 2 years 4) All children over 4 years of age.5) Cosmesis

-In girls must be repaired because the defect may worsen in pregnancy.

-some patients with umbilical defects develop acquired umbilical hernia due to increase in abdominal pressure due to ascitis

Mortality/Morbidity-Intestinal obstruction and infection-2-12% recurrence after the corrective operation.

-- A central venous catheter is required to monitor central venous pressure and blood gases in anticipation of postoperative hypovolemia from third space losses and for TPN.-Without removing the amniotic sac, a silicone rubber sheet

OMPHALOCELEIntroduction-Omphalocele is a congenital defect of the peri-umbilical abdominal wall in which the coelomic cavity is covered only by peritoneum and amnion (membrane covering). -There are two kinds of omphalocele: fetal and embryonic.-Fetal omphalocele is a small abdominal defect (< 4 cm wide) with herniation of bowel into a sac of amnion that has the umbilical vessels located at the apex of the sac. This is due to failure in development n the periumbilical abdominal wall after the first 8 weeks of gestation. Other anomalies are present in less than 10% of these patients. About 15% of congenital abdominal wall defects are fetal omphaloceles.-Embryonic omphalocele is due to failure of abdominal wall closure in the embryonic stage of development (before the eighth week). -It is characterized by a wide abdominal wall defect, usually greater than 4 cm in width, in which the amnion does not protrude far beyond the abdomen, and the umbilical cord joins the abdominal wall at the perimeter of the defect rather than at the apex. -Liver as well as bowel is herniated. Multiple anomalies are present in 50% of these cases, such as

Congenital heart defects (20%) (tetralogy of Fallot; atrial septal defect) Trisomies 21, D, and E; Diaphragmatic hernia Renal anomalies. Pentalogy of Cantrell -omphalocele is is epigastric in position and there is a defect in the

diaphragm and pericardium, allowing pericardial herniation of bowel, a split or shortened lower sternum, ventricular septal defect, and diverticulum from the heart--and a small thorax which may result in pulmonary hypoplasia

Beckwith-Wiedemann syndrome, in which a midabdominal omphalocele is associated with a baby who is large for gestational age and who has macroglossia, visceromegaly of

-An umbilical artery catheter can be maintained without interfering with the repair. -A bladder catheter can be used to monitor intra-abdominal pressure. - Most large embryonic omphaloceles cannot be closed without staging the procedure which gradual reduction of the omphalocele contents into the abdominal cavity and a secondary closure.

the kidneys, adrenal glands, and pancreas, hypoglycemia in early infancy, and a high frequency of hepatoblastoma, Wilms' tumor, or adrenocortical carcinoma; and

Hypogastric omphalocele associated with cloacal exstrophy and spinal dysraphism.

Treatment-Omphaloceles with small abdominal defects can be treated by excising the omphalocele sac and reapproximating the linea alba and skin.Treatment & Prognosis-Small defects may be closed primarily after manually stretching the abdominal cavity. -Frequently, a staged approach is required. Initially, the bowel should be covered by forming a

tube from silicone-coated fabric and incorporating the protuberant bowel into the tube (silo). The end of the tube is tied off. As edema and shaggy membrane of the protuberant intestine are absorbed, the bowel will readily reduce into the abdominal cavity.-A gastrostomy is valuable in postoperative care of the baby, because gastrointestinal function is often slow to return.-The death rate for infants with gastroschisis has been

- Acute management of omphalocele involves covering the defect with a sterile dressing soaked with warm saline to prevent fluid loss.- A nasogastric tube should be placed on suction to minimize intestinal distention and allow decompression-Intravenous fluids and glucose, and antibiotics