Omphalocele and Gastroschisis

Which defect you have changes the workup - Gastroschisis is a bowel problem; omphalocele is a syndrome problem. Before an omphalocele goes to the OR, chase the associated anomalies: echocardiogram for the atrial septal defect or tetralogy of Fallot seen in 30% to 50% of cases, and a serum glucose in Beckwith-Wiedemann syndrome, where neonatal hypoglycemia is part of the phenotype.

An intact sac buys you time - There is no urgency to close an omphalocele while the membrane is intact. That interval is for completing the cardiac and renal evaluation and correcting electrolytes. Gastroschisis has no membrane, so the bowel is protected in the delivery room with saline dressings and a lower-body plastic bag that also lets you watch bowel perfusion.

Delay surgery until the neonate is optimized - Complete blood count and type and screen, a metabolic panel with electrolyte derangements corrected, and hold the case until hemodynamic and cardiopulmonary problems have been addressed.

Treat both as a full stomach - Aspiration risk is increased in gastroschisis and omphalocele alike. Nasogastric or orogastric suction to decompress the stomach, and a rapid intubation strategy. Position in slight reverse Trendelenburg on induction so the herniated contents fall away from the chest.

The apneic window is short - Pulmonary hypoplasia, incomplete alveolar maturation and increased oxygen demand all shorten the time to desaturation. Most omphalocele infants have a small thorax with some degree of pulmonary hypoplasia, and mechanical ventilation may be needed for weeks to months.

Heat and evaporative losses are the dominant fluid problem - Evaporative fluid loss through exposed bowel runs about 2.5 times that of a healthy newborn, so maintenance fluids are given at two to three times normal. Temperature monitoring is part of the standard monitors here, not an optional extra.

But do not over-resuscitate - Over-resuscitation causes bowel and total body edema, lengthens the time to abdominal wall closure and raises the risk of abdominal compartment syndrome. Titrate to urine output, blood pressure and surgical losses rather than to a fixed volume.

No nitrous oxide - N2O diffuses into and expands bowel gas, which works directly against a reduction that is already fighting for abdominal space.

Paralyze for the closure - Neuromuscular blockade helps both abdominal wall closure and ventilation.

Watch the pressure during reduction - Returning the viscera decreases diaphragmatic excursion, compresses the lungs and raises airway pressures. Rising peak inspiratory pressure is your early warning. Talk to the surgeon and follow measured intra-abdominal pressure — above 10 to 15 mmHg renal and intestinal perfusion fall off, and above 20 mmHg it correlates with organ dysfunction.

Lines - Enough IV access to resuscitate, an arterial catheter for beat-to-beat hemodynamics plus repeated gases and electrolytes, and consider a PICC or central line for fluid management and postoperative TPN.

Glucose and blood - Monitor glucose closely and correct as needed. Blood loss is usually minimal, but transfusion may be required for larger defects, so have the type and screen done.

Dusky bowel means malperfusion - If tachycardia, low blood pressure or a dusky bowel suggests vascular compromise in an omphalocele, position the infant left side down, right side up.

Disposition - These neonates go to the NICU, most of them still ventilated. Intra-abdominal pressure monitoring continues postoperatively; rising pressure shows up as respiratory insufficiency and falling bowel and organ perfusion.

Omphalocele and gastroschisis are congenital anterior abdominal wall defects that leave abdominal contents outside the newborn, but they are different problems with different risk profiles. Gastroschisis is a full-thickness paraumbilical defect, almost always to the right of an otherwise normal cord insertion, with no covering membrane — bowel has been sitting in amniotic fluid and emerges matted, dilated and coated in a fibrinous inflammatory rind. Associated anomalies are uncommon (about 10% to 20%, mostly intestinal atresia or stenosis) and survival exceeds 90%.

Omphalocele herniates through the base of the umbilical cord and is covered by a peritoneal membrane, with the cord inserting onto the sac. It carries a 50% to 70% rate of associated anomalies — cardiac defects in 30% to 50%, trisomies, Beckwith-Wiedemann syndrome — and survival is 40% to 70%. Exposed viscera drive heat and evaporative fluid loss; reducing them drives intra-abdominal pressure.