Anemia of Prematurity - Portal Neonatal

Indomethacin is used prophylactically at some institutions and is administered in the first 24 hours of
life to close a PDA in anticipation of the deleterious effects of a continued PDA in an ELBW infant.
Some evidence suggests that prophylactic use of indomethacin has led to decreased symptomatic
PDAs and PDA ligations in ELBW infants. Concerns regarding indomethacin and its effects on
cerebral and renal blood flow have led to the investigation of the role of intravenous ibuprofen as an
agent to close a PDA in preterm infants.
Infection
Infection remains a major contributing factor to the morbidity and mortality of ELBW infants and can
present at any point in the clinical course. Early infection that occurs during the first 3-4 days of life is
believed to result from maternal factors, particularly if chorioamnionitis was diagnosed prenatally.
Late nosocomial infections typically occur after the first week of life and result from endogenous
hospital flora. Signs of infection are myriad, may be nonspecific, and include temperature instability
(hypothermia or hyperthermia), tachycardia, decreased activity, poor perfusion, apnea, bradycardia,
feeding intolerance, increased need for oxygen or higher ventilatory settings, and metabolic acidosis.
Laboratory studies may include complete blood count with differential, blood culture, cerebrospinal
fluid culture, urine culture, and cultures from indwelling foreign bodies, such as central lines or
endotracheal tubes.
The most common causes of early sepsis in the immediate newborn period are group B streptococci
(GBS), Escherichia coli, and Listeria monocytogenes. Nosocomial sources of infection include
coagulase-negative staphylococci (CoNS), and Klebsiella and Pseudomonas species, which may
necessitate a different antibiotic regimen than antibiotics typically started after birth for suspected
sepsis. CoNS and fungi, most commonly Candida albicans, are causes of late-onset sepsis and may
manifest with the above-mentioned symptoms and with thrombocytopenia. Importantly, fulminant
late-onset clinical sepsis rarely is caused by CoNS and is more commonly secondary to gramnegative
organisms. Late-onset sepsis is especially common in ELBW infants who have indwelling
catheters, and it may occur in as many as 40% of these infants.
In most institutions, first-line therapy in infants with early sepsis is with ampicillin and gentamicin or a
third-generation cephalosporin. Vancomycin should be reserved for proven CoNS infections and
organisms resistant to other agents to prevent the emergence of resistant organisms. Vancomycin
and a third-generation cephalosporin often are used to treat late-onset sepsis. Therapy with
amphotericin commonly is initiated in infants with fungal infections. Cultures should dictate antibiotic
management whenever possible.
Necrotizing enterocolitis
NEC is a disease of the premature gastrointestinal tract that represents injury to the intestinal
mucosa and vasculature. Incidence of NEC is associated with decreasing gestational age, and it is a
dreaded complication of premature birth. NEC accounts for 7.5% of all neonatal deaths. Risk factors
include asphyxia or any ischemic insult to the gastrointestinal blood supply. The role of enteral
feeding is controversial. Breast milk may have a protective effect but has not been shown to prevent
NEC.
Presenting symptoms may be vague and include apnea, bradycardia, and abdominal distention.
These symptoms can quickly progress to indicators of increasing sepsis, such as large gastric
residuals, metabolic acidosis, and lethargy. Radiographic findings include stacked bowel loops,
pneumatosis intestinalis (presence of gas in the bowel wall), portal venous gas, and free air, which
indicates perforation of the bowel and is an ominous sign of impending deterioration. NEC usually
presents close to the time that the infant is taking full enteral feedings, usually between the second
and third weeks of life.