Shad Baab
This chapter covers common neonatal problems that my present to the emergency department (ED). For discussion of fever and/or sepsis in the neonate, see Chapter 68.
In general, the signs and symptoms of illness are vague and nonspecific in neonates (ie, infants in the first month of life).
Improved survival of premature infants has increased the number of infants whose corrected gestational age (chronological age since birth in weeks minus number of weeks of prematurity) makes them similar to neonates. Some of these children have multiple medical problems and may present frequently to the ED.
Common neonatal ED complaints ranging from benign to critical are summarized in Table 69-1.
TABLE 69-1 Common Pediatric Emergency Presenting Complaints
NORMAL VEGETATIVE FUNCTIONS
Bottle-fed infants generally feed 6 to 9 times per 24-hour period, with a relatively stable pattern developing by the end of the first month of life. Breast-fed infants typically feed every 1 to 3 hours.
Infants lose 5% to 10% of their birth weight during the first 3 to 7 days of life. After this time, they are expected to gain about 1 ounce per day (20 to 30 grams) for the first 3 months of life.
The number, color, and consistency of stools vary from day to day. Normal breast-fed infants may go 5 to 7 days without stooling or have up to 9 stools per day. Color has no significance unless blood is present or stools are acholic (white). Typical neonatal stool is yellow with a mustard-seed appearance.
Respiratory rates in newborns vary, with normal ranges from 30 to 60 breaths per minute. Periodic breathing (brief pauses in respiration from 3 to 10 seconds alternating with short periods of tachyp-nea) is normal but may be frightening to parents.
Normal newborns awaken at variable intervals that can range from every 20 minutes to 6 hours. Neonates and young infants tend to have no day–night differentiation until about 3 months of age.
ACUTE, UNEXPLAINED, EXCESSIVE CRYING (INCONSOLABILITY)
There are multiple causes of prolonged crying in infants (Table 69-2), which range from benign to life threatening. Acute onset of inconsolable crying represents a serious condition in the majority of infants and requires careful evaluation.
Neonates and infants who present with excessive crying but have a normal head-to-toe physical examination, normal temperature and vital signs, and return to baseline in the ED can safely be discharged without further invasive testing.
TABLE 69-2 Conditions Associated with Uncontrollable Crying, Irritability, and/or Lethargy in Neonates
INTESTINAL COLIC
Intestinal colic is defined as crying for 3 hours or more per day for 3 or more days per week over a 3-week period. It is the most common cause of excessive (but not inconsolable) crying.
The cause of colic is unknown and the incidence is about 13% of all neonates. Colic seldom lasts beyond 3 to 4 months of age but can produce significant stress in caregivers and is a risk factor for nonaccidental trauma. Colic is benign and reassurance is usually all that is required.
NONACCIDENTAL TRAUMA (CHILD ABUSE)
A battered child may present with unexplained bruises at varying ages, skull fractures, intracranial injuries, extremity and/or rib fractures, cigarette burns, retinal hemorrhages, or unexplained irritability, lethargy, or coma (see Chapter 189 for detailed discussion).
GASTROINTESTINAL SYMPTOMS
SURGICAL CONDITIONS
Surgically treated abdominal emergencies in neonates are uncommon, but may present with nonspecific symptomatology, and when suspected require prompt consultation with an experienced pediatric surgeon.
The most common signs and symptoms are nonspecific and include irritability and crying, poor feeding, vomiting, constipation, and abdominal disten-tion. Bilious vomiting is suggestive of malrotation with midgut volvulus and requires emergent surgical consultation and radiologic evaluation (upper GI contrast study) prior to ED discharge. A groin or scrotal mass may represent an incarcerated hernia or testicular torsion, and should be evaluated with ultrasound.
FEEDING DIFFICULTIES
Parents may present to the ED with the perception of inadequate oral intake. If the patient’s weight gain is appropriate and the infant appears satisfied after feeding, simple reassurance is appropriate. A successful trial of feeding in the ED can reassure parents, ED nurses, and physicians alike.
Anatomic abnormalities interfering with feeding or swallowing (eg, esophageal stenosis, esophageal stricture, laryngeal clefts, and compression of the esophagus or trachea by a double aortic arch) typically present with difficulty feeding from birth, choking or gagging with feeds, failure to thrive, and dehydration.
Infants with a recent and actual decrease in intake usually have acute disease, most commonly infection, and warrant further evaluation.
GASTROINTESTINAL REFLUX
Gastroesophageal reflux in neonates and infants is universal, although variable in severity, and caused by reduced lower esophageal sphincter pressure and relatively increased intragastric pressure.
Reflux of a small amount of feedings regurgitated through the mouth or nose is typically a self-limited condition; in the well-appearing and growing infant, reassurance alone is appropriate.
Although rare, reflux associated with poor weight gain, respiratory symptoms, fussiness, or feeding aversion requires a more thorough evaluation. If dehydration or persistent respiratory symptoms are present, inpatient evaluation should be considered.
VOMITING
Vomiting is differentiated from regurgitation by forceful contraction of the diaphragm and abdominal muscles. Vomiting has a variety of causes and is rarely an isolated symptom.
Vomiting from birth is usually due to an anatomic anomaly (eg, tracheoesophageal fistula, duodenal atresia, midgut malrotation) and often diagnosed prior to discharge from the nursery.
Vomiting is a nonspecific but serious symptom in neonates. Diverse etiologies include increased intracranial pressure (eg, shaken-baby syndrome), infections (eg, urinary tract infections [UTIs], sepsis, gastroenteritis, meningitis), hepatobiliary disease (usually accompanied by jaundice), and inborn errors of metabolism (usually accompanied by hypoglyc-emia or metabolic acidosis).
Pyloric stenosis most commonly presents between 6 weeks and 6 months of age with nonbilious, projectile vomiting after feeding in the hungry infant. Classically an olive-shaped mass can be palpated on abdominal examination, and measurement of electrolytes may reveal hypochloremic alkalosis, but these signs are present in less than 10% of cases in neonates at the time of diagnosis. Diagnosis is made with pyloric ultrasound or upper GI radiography. Treatment is surgical after correction of electrolyte abnormalities.
Bilious vomiting in a neonate should be considered a surgical emergency until proven otherwise.
DIARRHEA
The most common causes of blood in the stool in infants less than 6 months of age are cow’s milk intolerance and anal fissures. Breast-fed infants may have heme-positive stool from swallowed maternal blood due to bleeding nipples. Although bacterial enteritis is a cause of bloody diarrhea, it is rare in neonates.
Oral rehydration should be attempted if the patient is less than 5% dehydrated (see Chapter 75 for detailed discussion of dehydration in infants) with a total intake goal of 150 cc/kg/d.
Dehydrated neonates (and neonates with impending dehydration from rotavirus) should be admitted for rehydration. Although routine electrolyte measurement is not helpful in older children, infants <6 months of age have a higher incidence of sodium abnormalities and serum electrolytes may help guide therapy.
Necrotizing enterocolitis may present with bloody diarrhea, although usually with accompanying signs of serious illness (eg, jaundice, lethargy, fever, poor feeding, and abdominal distention). Abdominal radiography may demonstrate pneumatosis intestinalis, hepatic portal air, or free air. Treatment includes bowel rest and broad-spectrum antibiotics (clindamy-cin, cefotaxime, and ampicillin) and pediatric surgery consultation.
ABDOMINAL DISTENTION
Relatively large abdominal girth can be normal in the neonate and is usually due to lax abdominal muscles and relatively large intra-abdominal organs. In general, if the neonate appears comfortable and is feeding well, and the abdomen is soft, there is no need for concern.
CONSTIPATION
Infrequent bowel movements in neonates do not necessarily mean that the infant is constipated. Stool patterns are variable, with normal ranging from multiple bowel movements per day to intervals of up to a week. Painful, hard, or pencil-shaped infrequent stools, by contrast, are more likely to signal underlying abnormalities.
Normal newborns pass meconium in the first 24 hours of life; failure to stool in the first 2 days of life may be associated with intestinal stenosis or atresias, Hirschsprung’s disease, and meconium ileus or plug associated with cystic fibrosis. A perinatal stooling history should be obtained in all patients presenting to the ED for evaluation of constipation.
CARDIORESPIRATORY SYMPTOMS
BREATHING AND STRIDOR
Noisy breathing in a neonate is usually benign. Infectious causes of stridor seen commonly in older infants and young children (eg, croup) are rare in neonates.
Stridor in a neonate is often due to a congenital anomaly, most commonly laryngomalacia. Other causes include webs, cysts, atresias, stenoses, clefts, and hemangiomas.
Neonates are obligate nasal breathers and feed for relatively prolonged times, breathing only through their noses (having the bottle or breast occlude the mouth). Nasal congestion from upper respiratory tract infections can cause significant respiratory distress. The use of saline drops and frequent nasal bulb suc-tioning is often effective.
APNEA AND PERIODIC BREATHING
Periodic breathing is normal in neonates.
Apnea is the cessation of respiration for 20 seconds, or less when accompanied by bradycardia, cyanosis, or change in muscle tone. Apnea generally signifies critical illness or injury, and further investigation and admission for monitoring should be considered (see Apparent Life-Threatening Event below).
Apnea may be the first sign of bronchiolitis with respiratory syncytial virus (RSV) in neonates and often occurs before wheezing. Neonates and young infants with documented apnea and clinical bronchiolitis require admission to the hospital, even when other signs of disease are mild. Apnea is also associated with pertussis and chlamydia infections in young infants.
CYANOSIS AND BLUE SPELLS
Many disorders can present with cyanosis, and differentiating among them can be a challenge. However, some symptom patterns are helpful.
Rapid, unlabored respirations and cyanosis suggest cyanotic heart disease with right-to-left shunting (see Chapter 74, Pediatric Heart Disease).
Irregular, shallow breathing and cyanosis suggests sepsis, meningitis, cerebral edema, or intracranial hemorrhage.
Labored breathing with grunting and retractions is suggestive of pulmonary disease such as pneumonia, aspiration, or bronchiolitis.
All cyanotic neonates should be admitted to the hospital for monitoring, therapy, and further investigation.
BRONCHOPULMONARY DYSPLASIA
Premature infants who required prolonged mechanical ventilation in the neonatal intensive care unit (NICU) may have residual lung injury and bronchop-ulmonary dysplasia (BPD). Young infants with BPD may be on home oxygen, diuretics, bronchodilators, or steroids.
Infants with BPD can have respiratory deterioration due to acute illnesses, including bronchiolitis, pneumonia, dehydration, sepsis, gastroesophageal reflux with aspiration, and congestive heart failure.
The most common cause of acute respiratory deterioration in an infant with BPD is a lower respiratory tract infection. RSV infections are particularly common and may be quite severe.
Basic treatment for BPD exacerbations includes oxygenation and bronchodilators. Antibiotics, admission, and mechanical ventilation may be required based on the clinical presentation.
JAUNDICE
There are multiple causes of jaundice, and the likelihood of each is based on the age at which the patient first develops signs.
Jaundice that occurs within the first 24 hours of life is pathologic. The most likely causes include ABO or Rh incompatibility, congenital or acquired infections, or birth trauma that produces severe bruising or cephalohematoma.
Jaundice that develops during the second or third day of life is usually physiologic. Classically the bilirubin rise is slow with a peak less than 6 milligrams/dL. It is more common in breast-fed infants and rarely requires treatment.
Jaundice that develops after the third day of life is usually pathologic. Causes include sepsis, congenital or acquired infections (eg, UTI), congenital hemolytic anemias, breast-milk jaundice, hypothyroidism, and hepatobiliary disease.
Diagnostic evaluation includes direct and indirect bilirubin levels in well-appearing infants with suspected benign causes of jaundice. If other pathologic conditions are suspected, evaluation is guided by the suspected differential (septic workup, including a lumbar puncture, a peripheral blood smear and reticulocyte count, liver function tests). Empiric antibiotics should also be administered when sepsis is suspected.
Phototherapy and exchange transfusion treatment thresholds for hyperbilirubinemia are guided by nom-ograms from the AAP, which can be found online at http://aappolicy.aappublications.org/cgi/content/full/pediatrics;114/1/297.
ORAL THRUSH
Oral thrush may prompt a visit to the ED because the parent notices something white in the mouth or because the discomfort from extensive lesions interferes with feeding. Intraoral lesions due to candida are white, adherent, and may be noted on the tongue, lips, or buccal mucosa.
Treatment consists of the topical application of oral nystatin suspension.
APPARENT LIFE-THREATENING EVENTS
An apparent life-threatening event (ALTE) is defined as an episode that is frightening to the observer and involves any combination of apnea, color change (pallor, plethora, or cyanosis), change in muscle tone (limp or stiff), choking, or gagging.
An ALTE is a symptom (or constellation of symptoms) for which the emergency physician must look for an underlying diagnosis. Many of the symptoms in an ALTE can represent normal or expected infant phenomena (eg, periodic breathing, reflux, acrocya-nosis), but perilous etiologies are also possible.
A careful history and physical examination will help differentiate between benign and serious events. Particular attention should be paid to past history of prematurity, respiratory or feeding difficulties, infant siblings with unexplained death, stillbirths or miscarriage, as well as the duration of event, contemporaneous events (feeding, sleeping, vomiting, etc.), changes in color or motor tone, and infectious exposures.
The differential diagnosis for an ALTE is broad and listed in Table 69-3.
TABLE 69-3 Reported Final Diagnoses for Patients Presenting with Apparent Life-Threatening Event
Gastroesophageal reflux disease (GERD) is ubiquitous in infancy and usually represents a benign physiologic process in which gastric contents are regurgitated into the esophagus. In pathological cases, complications including severe discomfort, failure to thrive, and aspiration can occur. GERD is problematic in the evaluation of ALTE because it can produce symptoms that trigger an ED visit in both physiological and pathological forms.
The evaluation for an ALTE depends on the history of the event and the patient’s condition in the ED.
Stable patients with clear diagnoses (eg, witnessed seizure in ED that is identical to episode that prompted visit) can be managed according to etiology.
Unstable patients should be resuscitated according to Pediatric Advanced Life Support (PALS) guidelines and have a differential diagnosis and diagnostic workup similar to stable patients without a clear diagnosis (by far the largest group of patients).
Stable patients without a clear diagnosis are the largest group; screening labs (ABG, CBC, BMP, glucose, EKG, head CT, and fundoscopic examination) are directed by the history and physical examination, and can often be deferred to the inpatient team.
Admission is usually required for any infants less than 2 months of age. Infants greater than 2 months with a clear and benign diagnosis (eg, reflux with choking episode), strong social support, reliable parents, and close primary care follow-up can be considered for discharge if both the physician and the family are confident in the diagnosis and its benign nature.
Home apnea monitors have not been shown to affect outcomes and are not recommended.
SUDDEN INFANT DEATH SYNDROME
Sudden infant death syndrome (SIDS) is the unexpected death of an infant under 1 year of age for which no cause can be determined by history, physical examination, postmortem examination, or scene investigation.
Patients should be resuscitated per PALS guidelines with the exception of patients with rigor mortis, dependent livedo, initial serum pH <6, or significant hypothermia without explanatory environmental exposure.
If resuscitation is unsuccessful, the treating physician must report the death to the medical examiner, but should not sign the death certificate as the medical examiner will complete the certificate after autopsy. The physician should also strongly consider involving the primary care physician, chaplain, and social worker (after discussion with the family).
For further reading in Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 7th ed., see Chapter 111, “Neonatal Emergencies and Common Neonatal Problems,” by Quynh H. Doan and Niranjan Kisson.