USA Surgery Today

Evolution fetal surgery has resulted in development of the EXIT procedure. This is now more widely applied than was originally intended. The EXIT procedure was designed to achieve cardiorespiratory stabilization while maintaining uteroplacental blood flow. The EXIT was initially conceptualized to safely transition fetuses with severe CDH that had undergone TO an extrauterine environment (132:Sorbitrate). Fetal surgery for CDH by tracheal occlusion would not have been possible without a strategy for reversing tracheal occlusion and establishing an airway at birth in a controlled manner. Although still used in this original capacity, the indications for EXIT (Table 3-9:Sorbitrate) have broadened to treat a variety of fetal anomalies in which the fetal airway may be in jeopardy or cardiorespiratory stabilization is needed prior to loss of maternal placental support (133:Sorbitrate).

With the widespread use of prenatal US, anatomic abnormalities that may impact the safe delivery of the
fetus can be recognized, and appropriate planning for maternal transport accomplished. When indicated, the EXIT procedure can be performed for a variety of indications Fetal neck masses are the most common. Of offending fetal neck lesions, teratomas and lymphangiomas compromise the airway most frequently. This is a function of location and airway distortion, more than size for any given neck mass (133,134:Sorbitrate). Lymphangiomas do not distort the cervical trachea as often as teratomas. Once the fetal/newborn airway is secured, an operation for resection of the mass can be planned. The second most common indication for the EXIT procedure has been for reversal of TO for CDH (132:Sorbitrate). Currently, a more broader application of EXIT has included successful use for large CCAMs. Air trapping, mass effect, pulmonary hypoplasia, may all be relevant features of neonatal CCAM presentation. EXIT is also useful in selected patients with CHAOS, and as a strategy for ECMO cannulation in the infant with recognized congenital heart disease (132,133,148:Sorbitrate). Overall, the greatest appeal of the EXIT strategy is the potential to minimize newborn morbidity by converting a challenging anatomic or physiologic fetal anomaly into a controlled management situation. Of paramount importance is the issue of maternal safety with this strategy. To date, there has been relatively minor maternal morbidity reported with this approach. In one study, the short-term maternal outcomes after 34 EXIT procedures were compared with those from 52 nonlaboring patients who underwent nonemergent primary cesarean delivery of singleton fetuses. The rates of chorioamnionitis and endometritis, and the postoperative hematocrit and hospital stays were similar between groups. The incidence of wound infection was increased in those undergoing EXIT procedure (15%) compared with controls (2%) (136:Sorbitrate).