Pediatric emergency medicine trisk 366

present with bilious emesis, tenderness to palpation, irritability, and possibly
bloody stools if there has been significant intestinal ischemia. Hirschsprung
enterocolitis may present a history of difficulty passing meconium and with
similar symptoms due to a large bowel obstruction. There may be an explosive
release of stool on digital rectal exam. In all these conditions, fluid requirements
are significantly increased because of bowel wall edema. Plain films including
AP and left lateral decubitus views are indicated to evaluate for obstruction, and
contrast studies (upper GI series for volvulus, contrast enema for intussusception,
and Hirschsprung enterocolitis) may be required to make a definitive diagnosis if
the patient is stable.
Pyloric stenosis causes severe vomiting in the young infant. This is most often
seen in male infants 3 to 6 weeks old. An infant with pyloric stenosis may present
to the ED afebrile, with significant dehydration and lethargy. A careful history
reveals that increasingly projectile, nonbilious vomiting is the predominant
feature of the illness, and there may be a positive family history for pyloric
stenosis. The physical examination reveals the classic abdominal mass, or
“olive,” in less than half of the cases. Rarely, a peristaltic wave is noted to pass
over the epigastric area. Electrolytes typically show hypochloremia, hypokalemia,
and alkalosis. Ultrasound of the upper gastrointestinal tract confirms the
diagnosis.
Necrotizing enterocolitis (NEC) most often occurs in premature infants in the
first few weeks of life, but can also occur in term infants, usually within the first
10 days of life. A history of an anoxic episode at birth or other neonatal stresses
may precede NEC. These infants are quite ill, with lethargy, irritability, anorexia,
distended abdomen, and bloody stools. Radiographs of the abdomen may show
pneumatosis intestinalis caused by gas in the intestinal wall. Neonatal
appendicitis is another rare event, but several cases have been reported to closely
mimic sepsis. Rapid diagnosis is essential as mortality is high, and perforation
worsens the prognosis. The most common presenting signs are nonspecific and
can also be seen with SBO and NEC, including irritability, vomiting, and
abdominal distention. There may also be hypothermia, ashen color, and shock as

the condition progresses, as well as edema of the right abdominal wall and
possible erythema of the skin in that area. The WBC count may be elevated, with
a left shift, and there may be a metabolic acidosis as well as DIC. Ultrasound may
be unreliable in this age, and abdominal radiographs may show a paucity of gas in
the right lower quadrant, evidence of free peritoneal fluid, or a right abdominal
wall thickened by edema.

Neurologic Diseases


An unusual process that produces a sepsis-like picture is infant botulism (see
Chapter 94 Infectious Disease Emergencies ). The symptoms of this illness are
caused by neurotoxins elaborated by Clostridium botulinum. An infant with
botulism is afebrile with lethargy, a weak cry, and possibly dehydration. The
parents may note a gradual progression with this illness that is preceded by
constipation. The disease is associated with the ingestion of honey, breastfeeding,
a recent change in feeding practices, a rural environment, and/or nearby
construction. Infants are generally well perfused with normal cardiovascular
parameters (unlike sepsis), but notably hypotonic and hyporeflexic, and may have
increased secretions caused by bulbar muscle weakness. The presence of a facial
droop, ophthalmoplegia, and decreased gag reflex are consistent with botulism,
and are rare findings with sepsis. The diagnosis of infant botulism is usually made
clinically. A stool specimen that identifies toxins of C. botulinum is diagnostic,
but requires considerable time for identification. Electromyography will show
decreased muscle action potential with the “staircase” phenomenon in this
disease, but this is rarely performed.
A young baby with a ventriculoperitoneal shunt in place because of
hydrocephalus can develop serious complications that cause the baby to appear
extremely ill (see Chapter 122 Neurosurgical Emergencies ). Shunt infection
could present with fever and irritability. Abdominal tenderness may be found on

examination, as well as erythema or pus around the shunt itself. The definitive
diagnosis is made by shunt aspiration or lumbar puncture. Shunt obstruction may
result in increased intracranial pressure that causes a young infant to present with
lethargy or poor feeding. On examination, the baby may have bradycardia, apnea,
coma, opisthotonic posturing, bulging fontanel, or cranial nerve VI palsy. A CT
scan or fast MRI will demonstrate ventricle size and indicate the adequacy of
shunt function.

Child Abuse
Consider intracranial hemorrhage from child abuse in the very ill infant. (See
Chapter 87 Child Abuse/Assault and ED Clinical Pathway for
Evaluation/Treatment of Children with Physical Abuse Concerns;
/>).
Vigorous shaking of an infant or throwing the baby against a soft surface such as
a mattress or sofa can produce subdural or subarachnoid hemorrhages that may of
sufficient volume to cause shock. The history may or may not be helpful. A report
that the infant was well and is now suddenly in critical condition raises suspicion
of abuse. The parents may note that the child had respiratory distress at home;
only a few admit to shaking the infant. On examination, the infant may appear


gravely ill with apnea, bradycardia, hypothermia, bradypnea, or seizures.
However, a careful physical examination suggests abuse rather than sepsis.
Bruises may be present on the body, though more often, no external evidence of
trauma is present. Respiratory distress without stridor or lower airway sounds
may be due to central nervous system dysfunction. The head circumference is
often at or above the 90th percentile, and the fontanel may be full or bulging.
Retinal hemorrhages are often found and strongly suggest intracranial
hemorrhage from trauma. Some neurologic signs may be confused with
meningitis, such as nuchal rigidity, irritability, coma, seizures, or posturing.

Although the CBC often shows a leukocytosis and thus is confusing, the spinal
fluid from a shaken baby is usually bloody and fails to clear as the fluid is
collected. A noncontrast CT scan or magnetic resonance imaging (MRI) usually
demonstrates a small posterior, interhemispheric subdural hematoma. Such
shaken babies have a high incidence of serious morbidity and mortality.

EVALUATION AND DECISION
Presume that any infant who is critically ill in the first few weeks of life may be
septic. It is imperative to stabilize the baby rapidly ( Fig. 73.1 ) because this lifethreatening situation may respond to early treatment. Restore airway, breathing,
and circulation and obtain vascular access. Intraosseous access should be used if
IV access cannot be obtained rapidly, and the patient may require vigorous fluid
resuscitation. Perform rapid bedside testing for glucose. Unless another diagnosis
is immediately obvious, it is best to give intravenous antibiotics while pursuing
alternative diagnoses. If time permits, send cultures to the laboratory before
giving antibiotics. Administer prostaglandins if cardiogenic shock with PDA
closure is suspected.


FIGURE 73.1 Initial approach to the septic-appearing child. a Initial laboratory evaluation:
culture of blood, urine, usually cerebrospinal fluid, chest radiograph, complete blood cell count,
urinalysis, electrolytes, glucose, bicarbonate, and maybe arterial blood gas.