Written by David Wilson, MS, RNC
Despite advances in neonatal surgery techniques, mechanical ventilation, and intrauterine diagnosis, congenital diaphragmatic hernia (CDH) continues to have a high death rate (50 to 80%) (Wilson and others, 1997; Azarow and others, 1997) possibly due to associated congenital anomalies in 44 to 66 percent of all cases (Thibeault and Singalet, 1998). The two major problems encountered in the management of CDH are pulmonary hypoplasia and persistent pulmonary hypertension.
The two primary methods for treating CDH in utero are (1) repair of the herniated diaphragm, and (2) ligation of the fetal trachea, with subsequent stimulation of lung growth (O'Toole and others, 1997). Intrauterine repair of the herniated diaphragm may only take place if the umbilical vein/ductus venosus is visualized by ultrasound to be below the diaphragm to avoid compromising fetal-placental blood flow; a herniated fetal liver also precludes intrauterine repair.
Despite initial expectations that intrauterine diaphragmatic repair would be successful, the results have been unfavorable with high mortality rates from extrapulmonary causes (Mychaliska, 1997). In another experience with intrauterine CDH repair, fetal surgery was successful. However, there was no significant difference between survival of infants treated postnatally for CDH and the fetal surgery group (Harrison and others, 1997). Intrauterine surgery for CDH is also associated with an increase in the onset of preterm labor.
Tracheal obstruction in fetal lambs with CDH has been shown to expand the lungs and push the abdominal contents back into the abdomen, thus producing large, functional lungs. PLUG (Plug the Lung Until it Grows) has been used in human fetuses to increase lung growth. At the time of delivery the fetal chest is delivered by cesarean section but the lower body remains in utero with functional placental circulation until the trachea has been cleared and effective airway established. This is referred to as the EXIT (ex utero intrapartum treatment) (Mychaliska and others, 1997). A concern with the PLUG procedure was that surfactant production by type II pneumocyte cells would be reduced, causing respiratory distress syndrome. A study by Flageole and others (1998) did demonstrate that surfactant-producing type II cells were decreased in fetal lambs whose trachea remained plugged until birth. Fetal lambs, however, that had temporary plugging for 15 days did not have abnormal type II cell growth; these studies have yet to be replicated in human fetus models.
Postnatal treatment and management of CDH has changed in recent years due to improved ventilatory techniques and a better understanding of the causes of neonatal pulmonary hypertension. In some centers it has become common practice to stabilize the infant with CDH for several days prior to surgical repair, using a combination of any or all of the following: low mean airway pressures, partial liquid ventilation, high frequency oscillation, surfactant replacement therapy, extracorporeal membrane oxygenation (ECMO), and inhaled nitric oxide for several days prior to surgical repair. These centers report increased success rates with preoperative stabilization of CDH infants (Frenckner and others, 1997; Thibeault and Sigalet, 1998). In one large multicenter trial inhaled nitric oxide was not effective in reducing pulmonary hypertension (Kinsella and others, 1997).
The nursing implications for the infant with CDH are numerous. The family with a prenatal diagnosis of a fetus with CDH must be assisted in making a knowledgeable decision regarding available treatment options and the potential outcomes. Family support and assistance with prenatal ultrasound evaluation is essential. A visit to the neonatal intensive care center may help allay some fears. Meeting other parents who have a child with CDH may also be helpful. A conference with the ECMO team coordinator, surgeons involved , and the ecmologist may be arranged to answer the parents' questions regarding the anticipated procedures (Thibeault and Sigalet, 1998). Postnatal management in the delivery room involves immediate endotracheal intubation (if respiratory distress is evident) and ventilatory support, radiographic examination of the defect, and placement of a central venous or arterial line(s) for fluid management. Despite the critical nature of the demands of stabilization of the infant with CDH, the nurse must keep the parents appraised of the infant's condition and expected plan of action.Once the infant is stabilized it is important to allow the parents and siblings (as appropriate) to visit the infant and explain all equipment. Since sedation or paralysis may be used with ventilatory support the lack of infant reactions to the parents should be explained. Positive aspects of the infant's appearance are emphasized in keeping with the reality of the infant's condition. During the first few critical days of stabilization, parents may fear leaving the infant's side. The provision of a sleep room in close proximity , extended family support, and a pager for rapid notification in the event of condition changes are options for caring for the family. If the mother had intentions of breast feeding she should be provided with appropriate instructions for storing expressed breast milk. A bilateral breast pump may be helpful after her milk has "come in" to reduce time in pumping and allow more time to visit her infant. Since infants with CDH are prone to long term complications such as chronic lung disease, hyperactive airway, gastroesophageal reflux, food aversion, and decreased intestinal motility , nursing will have an ongoing relationship not only with the child but the family as well. Follow- up and nurse-based home care into toddler years may be a part of the care required to foster optimal growth and development of the infant with CDH. Integration into early intervention and development is an essential component of the nursing care of the infant with CDH.
Azarow K and others: Congenital diaphragmatic hernia — a tale of two cities: the Toronto experience. J Pediatr Surg 32(3):395-400,1997.
Flageole H and others: The plug-unplug sequence: an important step to achieve typeII pneumocyte maturation in the fetal lamb model. J Pediatr Surg 33(2):299-303,1998.
Frenckner B and others: Improved results in patients who have congenital diaphragmatic hernia using preoperative stabilization, extracorporeal membrane oxygenation, and delayed surgery. J Pediatr Surg 32(8):1185-1189,1997.
Harrison MR and others: Correction of congenital diaphragmatic hernia in utero VII: a prospective trial. J Pediatr Surg 32(11):1637-1642,1997.
Kinsella JP and others: Randomized, multicenter trial of inhaled nitric oxide and high-frequency oscillatory ventilation in severe, persistent pulmonary hypertension of the newborn. J Pediatr 131(1 Part 1):55-62,1997.
Mychaliska GB and others: In utero management of congenital diaphragmatic hernia. Clin Perinatol 23(4):823-841,1996.
Mychaliska GB and others: Operating on placental support: the ex utero intrapartum treatment procedure. J Pediatr Surg 32(2):227-230,1997.
O'Toole SJ and others: Tracheal ligation: the dark side of in utero congenital diaphragmatic hernia repair. J Pediatr Surg 32(3):407-410,1997.
Thibeault DW and Sigalet DL: Congenital diaphragmatic hernia from the womb to childhood. Curr Prob Pediatr 28(1):5-25,1998.
Wilson J M and others: Congenital diaphragmatic hernia — a tale of two cities: the Boston experience. J Pediatr Surg 32(3):401-405,1997.
See Chapter 24 in Essentials of Pediatric Nursing, 5th edition.
See Chapter 110 in Nursing Care of Infants and Children, 5th and 6th editions.
March 15, 2002