Apnea
Thomas Mollen
INTRODUCTION
The 1986 Consensus Statement on Infantile Apnea and Home Monitoring from the National Institute of Health (NIH) describes an apparent life-threatening event (ALTE) as “an episode that is frightening to the observer and is characterized by some combination of apnea (central or occasionally obstructive), color change (usually cyanotic or pallid but occasionally erythematous or plethoric), marked change in muscle tone (usually marked limpness), choking, or gagging … [I]n some cases, the observer fears that the infant has died … [P]reviously used terminology such as ‘aborted crib death’ or ‘near-miss SIDS’ should be abandoned because it implies a possibly misleading close association between this type of spell and SIDS.”
DIFFERENTIAL DIAGNOSIS LISTInfectious Causes
Sepsis
Pneumonia
Respiratory syncytial virus (RSV) infection
Viral upper respiratory tract infections
Meningitis
Pertussis
Gastrointestinal Causes
Gastrointestinal reflux (gastroesophageal reflux disease [GRD])
Traumatic Causes
Intracranial hemorrhage (subdural, subarachnoid)
Munchausen by proxy syndrome
Child abuse
Cardiovascular Causes
Cardiac arrhythmias
Congenital heart disease
Cardiomyopathy
Vascular ring
Respiratory Causes
Reactive airway disease
Laryngomalacia
Other airway anomalies
Structural lung malformation
Neurologic Causes
Seizure
Intracranial mass
Cerebral dysgenesis
Structural or cerebrovascular anomalies
Metabolic Causes
Inborn errors of metabolism
Hypoglycemia
Electrolyte imbalance
DIFFERENTIAL DIAGNOSIS DISCUSSION
Infection
Clinical Features
Although apnea can be the only initial symptom of infection, untreated sepsis progresses rapidly and the infant develops other signs and symptoms that suggest this diagnosis. Pneumonia or bronchiolitis caused by RSV can be associated with life-threatening apnea and is a significant cause of infant mortality among premature infants after hospital discharge, especially during the winter months.
Evaluation
In an infant who presents with acute apnea, a careful history and physical examination should be performed in an attempt to elucidate the presence of an acute infection. Depending on the history and physical examination findings, appropriate tests should be ordered.
Treatment
Treatment depends on the underlying infection. Effective antibacterial therapies, as well as some antiviral therapies, are available. Prompt diagnosis and treatment are essential.
Obstructive Apnea
Etiology
Obstructive apnea is the inability to effectively oxygenate, ventilate, or both, despite adequate central respiratory drive. The most common causes include the following:
Gastrointestinal reflux (GRD). The most common cause of obstructive apnea is GRD; as many as 20% of premature infants with apnea have an obstructive component.
Prematurity. The incomplete development of cartilaginous structures in a premature infant’s airway can lead to kinking of the airway and obstructive apnea.
Laryngeal webs or laryngomalacia can also present as obstructive apnea.
Clinical Features
The parents describe that their baby regurgitate formula or milk, either during or after the feedings. Infants may have “awake apnea,” which is most commonly caused by GRD. Alternatively, infants may struggle during feeding, with exaggerated respiratory effort.
Evaluation
