Hello, I am Debra Neiman, RN BSN. I have worked in Neonatal Care, at Beauregard Memorial Hospital, DeRidder for over four years. My college experience at Louisiana State University at Alexandria, resulted in a great deal of research papers, which are gathering dust in my office. My curriculum at Northwestern State University also added to this wealth of information. I hereby begin this series to provide a way to get this information to those in the nursing field and any other person with a passing interest in these subjects. Feel free to reference of use this information in your practice. However, please respect my Copyright and do not "BORROW" for your HOMEWORK assignments.

LinkExchange Member

INDEX:

• HANDOUT
• Pathophysiology
• Predisposing Factors
• Assessment
• Prevention
• Management of Suspected NEC
• POST TEST
• References Cited

Necrotizing Enterocolitis (NEC) is acute inflammation of the bowel, characterized by ischemic necrosis of GI mucosa that may lead to perforation and peritonitis. ( Wong & Whaley, 1990). The ileum is most often affected, but the ascending colon, cecum, transverse colon, and rectosigmoid may also be involved (Byrne, 1984).

---

Pathophysiology

The etiology of NEC is unknown. Although risk factors are identifiable, prediction of which infants will develop NEC is not reliable. The best way to prevent NEC is to prevent premature birth (Pickler & Terrell, 1994). Premature infants account for 90% of the cases of NEC. Onset is usually between 4 to 10 days, however, NEC may appear as early as 4 hours or as late as 30 days. Term infants generally develop early onset of NEC. Infants less than 26 weeks gestation tend to have NEC at an older age and thus have a longer duration of risk (Vanderhoof, Zach, & Adrian, 1994). There are between 2,000 and 4,000 cases of NEC in the United States each year or about 1% to 10% of NICU patients. Early identification is a priority and long-term prognosis of survivors appears to be the same as for infants without NEC (Kanto, Stoll, Child, Cotsonis, & Bain, 1988).

Prematurity is the leading risk factor for NEC. This may be due in part to the multifactor association of prematurity with neonatal asphyxia or hypoxia and an immature immunological system. Prenatal stresses such as maternal vaginal bleeding, pregnancy-induced hypertension, or maternal cocaine use are associated with increased incidence of NEC (Coon, 1992).

Risk factors for newborns in the NICU have been associated with umbilical catheters, exchange transfusions, hyperosmolar formulas, and microbial agents
( Vanderhoof et al., 1994).

The earliest and most common sign of NEC is a distended abdomen which is especially tense or rigid with gastric retention. Other signs include increased gastric residuals (2 ml or more) before feedings, decreasing bowel sounds, and bile stained vomitus. Occult blood in stool (positive guaiac test) may be attributed to rectal fissures, although, about 25% of NEC cases will have bloody diarrhea. A taut abdomen with red or shiny skin is indicative of peritonitis. Non specific symptoms include thermal instability, apnea, bradycardia, metabolic acidosis, lethargy, poor feeding, vomiting, pallor or jaundice (Massoni, 1991).

The best prevention is to reduce prenatal complications and prevent premature labor. NEC has been associated with immaturity of the intestinal mucosal barrier in the premature newborn. After the newborn is delivered, aggressive treatment of hypoxia is necessary to prevent a "diving reflex" of shunting blood away from the intestine. It has been suggested that this mechanism may be responsible for the initial ischemia of the tissues of the gut in an infant with hypoxia (Vanderhoof et al., 1994).

Careful handling of the newborn, using nesting support in the incubator, protecting the thermal homeostasis, and reducing oxygen requirements may provide a degree of protection for the infant at risk (Pickler & Terrell, 1994).

Breastfeeding does not totally eliminate the risk of NEC, but it greatly reduces the incidence. This is attributed to the early milk, colostrum, which contains a high concentration of immunoglobulin A which directly protects the newborn gut from infection. Breastmilk has a low pH which inhibits growth of many organisms and also contains live macrophages to fight infection. Breastfeeding mothers may pump their breasts to feed their premature newborns in the special care area. Nurses should be aware of the need to feed the milk specimens in the order it was pumped. Also instruct the mother not to freeze or expose the milk to high heat. This will destroy helpful antibodies. Also, the milk should be stored in plastic containers only. Leukocytes in the milk will adhere to a glass container and not be provided to the newborn. Breastmilk may be refrigerated up to 48 hours ( Massoni, 1991).

Whaley & Wong recommends putting two drops of formula into the newborn's mouth and allowing pacifier use during gavage feedings to aid the development of suck-swallow coordination ( 1990). Recent research supports the use of a pacifier for nonnutritive sucking (NNS). Reduced incidence of NEC, improved oxygenation during gavage feeding, reduced heart rate, and improved weight gain have been strongly correlated to the use of NNS. Pacifier use provides the newborn a more rapid transition from gavage feedings to bottle feeding, with improved bottle feeding performance, and increased alertness before bottle feeding. This results in shorter hospital stays (Pickler & Terrell, 1994).

Research supports two suggestions for the reduction of incidence of NEC in infants supported with NNS. Vagus nerve stimulation by NNS is the first suggestion and is strongly supported by several studies. Vagal stimulation increases insulin secretion and may improve glucose utilization. Increased gastrin secretion is also reported, which stimulates acid secretion, gastric motility and growth of intestinal mucosa. Somatostatin secretion is also reported to be reduced with NSS during gavage feedings. This reduction results in increased gastric emptying (Pickler & Terrell, 1994).

Secondly, NNS during gavage feeding of the premature newborn is associated with helping achieve optimal behavior states, which provides for reduction in energy expenditures and improved neurobehavioral organization. When used before bottle feedings, NNS reduces restless states, increase quiet alert state and readiness to nurse. After bottle feeding, NNS promotes a more rapid transition to the quiescent behavior state (Pickler & Terrell, 1994).

Notify physician of observations and change in status. Abdominal circumferences should be documented. Assessment of abdominal bowel sounds, gastric residuals, changes in level of activity, muscle tone, color, and vomiting is essential. Infant should be held NPO and nasogastric tube open to air to reduce gastric distention. Maintain a safe environment, protecting temperature stability, and reducing oxygen requirements. Prevent pressure on abdomen and leave diaper off or loosely taped. Position the infant on the side or back, DO NOT PLACE PRONE. Promote asepsis and follow strict handwashing (Wong & Whaley, 1990).

Diagnosis is confirmed by abdominal anteroposterior and lateral x-ray. Implement specific therapy as ordered. Anticipate orders for NPO, gastric suction, IV fluids and antibiotics, and transfer to NICU. Share information with family, providing support and anticipatory guidance (Massoni, 1991).

1. Necrotizing enterocolitis may be associated with:


• a. Gestational Diabetes and hypoglycemia
• b. MgSO4 use in the mother during labor
• c. Umbilical line placement in a premature newborn

2. Reducing the risk of necrotizing enterocolitis may be accomplished by:


• a. Preventing premature labor
• b. Breastfeeding and nonnutritive sucking
• c. Rapid treatment of newborn asphyxia
• d. All of the above

3. The earliest sign of necrotizing enterocolitis is:


• a. Shiny red abdominal skin
• b. Bloody stools
• c. Abdominal distention with gastric retention

4. An infant suspected of having should NEC should be:


• a. Positioned Prone with diaper loose
• b. Positioned on Side or Back with diaper loose
• c. Positioned in Semi Fowlers with diaper loose

5. Treatment for necrotizing enterocolitis includes:


• a. Hyperosmolar formula, IV fluids, and antibiotics
• b. NPO, IV fluids, and antibiotics
• c. Parental fluids and feedings through umbilical line

6. An important factor in preventing NEC in the Newborn Unit is:


• a. Handwashing
• b. Maintaining NTE
• c. Careful handling of premature infants
• d. All of the above

KEY: c, d, c, b, b, d

Byrne, W. J. (1984). Disorders of the intestines and pancreas: Necrotizing

enterocolitis. In H. W. Taeusch, R. A. Ballard, & M. A. Avery (Eds.), Schaffer and

Avery's Diseases of the Newborn (6th ed.), pp. 686-689. Philadelphia: Saunders.

Coon, S. L. (1992). Neonatal necrotizing enterocolitis (NEC). AJN/MOSBY Nursing

Boards Review for the NCLEX-RN Examination (8th ed.), pp. 391-392.

St. Louis: Mosby.

Kanto, W., Stoll, B., Child, C., Cotsonis, G., & Bain, R. (1988). The cost of

necrotizing enterocolitis. Perinatrology-Neonatology, 12(1), 32-34.

Marquis, B. L. & Huston, C. J. (1992). Leadership Roles and Management

Functions in Nursing: Theory and Application. Philadelphia: Lippincott.

Massoni, M. (1991). Gastrointestinal care: Necrotizing enterocolitis. In Illustrated

Manual of Nursing Practice (pp. 734-735). Springhouse, Pennsylvania: Springhouse.

Pickler, R. H. & Terrell, B. V. (1994). Nonnutritive sucking and necrotizing

enterocolitis. Neonatal Network, 13(8), 15-18.

Vanderhoof, J., Zach, T., & Adrian, T. (1994). Abnormalities of the gastrointestinal

tract: Necrotizing enterocolitis. In G. B. Avery, M. A. Fletcher, & M. G.

the Newborn (4th ed.), pp. 614-615. Philadelphia: Lippincott.

Wong, D. L. & Whaley, L. F. (1990). Clinical Manual of Pediatric Nursing

(3rd ed.), p. 312. St. Louis: Mosby.

Copyright, ©1997 Debra Kay Neiman, RN BSN
E-Mail me at: crystalblue@usa.net