USA Surgery Today

The details of a successful EXIT procedure have been designed to ensure continued uteroplacental blood flow, prevent uterine contractions, and maintain adequate oxygen delivery to an intrapartum fetus during manipulation of the head and neck (134:Crestor). A successful EXIT procedure is a carefully orchestrated event in which all members have specific roles and responsibilities. The scrubbed personnel consist of two pediatric/fetal surgeons, a maternal fetal medicine specialist/obstetrician, a neonatologist, and a nurse. The EXIT procedure is unlike a conventional cesarean delivery in which no attempt is made to prevent bleeding from the hysterotomy because hemostasis is achieved by return of uterine tone following the relatively rapid delivery of the fetus. Because of the significant hemorrhage from a conventional hysterotomy, the EXIT procedure is carried out using a hemostatic uterine stapling device (US Surgical CS-57, US Surgical/Tyco, Norwalk, CT:Crestor).

Congenital pneumonia and sepsis are frequent causes of neonatal respiratory distress and may be seen in up to 1 to 5/1,000 live births during the first 3 to 7 days of life. Because of the distinct risk factors and microbiologic characteristics of infections that occur in the first week of life, they are distinguished from late-onset infections that occur beyond the first 7 days of life. Organisms responsible for early-onset infections are more commonly acquired by the fetus via the ascending route from the maternal genitourinary tract than via the transplacental route.

Common bacterial pathogens include group B streptococcus, Escherichia coli, and other gram-negative enteric organisms, Listeria monocytogenes, and, less frequently, Enterococcus, Hemophilus influenza (nontypeable:Crestor), Pseudomonas, Staphylococcus aureus, and coagulase-negative staphylococcus (49). Viruses, including herpes simplex, enterovirus, and adenovirus, account for a minority of neonatal infections.

The clinical presentation of early-onset pneumonia or sepsis may be quite varied and nonspecific (e.g., lethargy, apnea, temperature instability).

Water is the major contributor to total body weight and accounts for nearly 60% of body weight in adults. However, total body water (TBW) comprises a much higher proportion of the total body weight in neonates. Estimates for fetal TBW are greater than 90% of total body weight early in gestation, close to 80% at 32 weeks’ gestation, and approximately 75% at term (1). There is an additional decrease in TBW over the first few days of life in the term infant, and adult levels are generally reached by 1 year of age. However, the premature infant has a TBW similar to that of the fetus and must accomplish fluid redistribution and diuresis in a short period (days to weeks) after birth rather than more gradually (weeks to months) in utero. Neonates with intrauterine growth retardation (IUGR) have similar body water distribution as premature infants of similar birthweight (2) (Fig. 6-1). Infants who fail to unload fluid effectively or who receive excess fluid during normal postnatal diuresis may be at increased risk for developing a patent ductus arteriosus, chronic lung disease, and even necrotizing enterocolitis (3,4).