• Lack of airflow secondary to cessation of breathing
• Absence of drive to breath from the central nervous system

• Lack of airflow secondary to airway obstruction
• Paradoxical chest-wall motion frequently seen
• Respiratory drive present

• Central and obstructive events occurring together

• Physiological
  • Prematurity or immature respiratory control center
• Infection
  • Meningitis
  • Viral meningoencephalitis
  • Respiratory syncytial virus (RSV)
  • Pertussis
• Gastrointestinal
  • Reflux
  • Aspiration
• Neurological
  • Asphyxia
  • Laryngeal chemoreflex
  • Seizure
  • CNS malformations
  • Cerebral or intraventricular hemorrhage
  • Masses and congenital central hypoventilation
• Pharmacological
  • Accidental drug ingestion
  • Ethanol
  • Sedatives
  • Narcotics
  • Toxins
• Metabolical
  • Hypoglycemia
  • Hypoxia
  • Hypocarbia
  • Overheating
• Anemia
  • Genetic/Familial Disorders
    • Werdnig-Hoffmann
    • Familial dysautonomia
  • Behavioral
    • Breath-holding spells
    • Excitement
    • Agitation
  • Epidemiology
    • Over 50% of premature infants will develop apnea.
    • Premature infants usually outgrow their apnea when they reach term age.
    • Some infants may exhibit apnea of over 20 seconds in duration without apparent adverse effects.
    • Pathological apnea in full-term infants not caused by gastroesophageal reflux (GER) is rare.
  • Complications
    • Apparent life-threatening events (ALTE) refer to apneic events that to the child’s caretaker appear life-threatening [incorrectly referred to as “near-miss” SIDS (sudden infant death syndrome) or “aborted SIDS” events]

• In general, good. Most infants outgrow apnea of prematurity/immaturity at term or within 1 to 2 months of age.
• Obstructive apnea is often cured with surgery (tonsil and adenoidectomy; uvulopharyngopalatoplasty)
• Resolution of apena otherwise dependent on its cause (i.e., GER, infection, etc.) and available treatment.
• Less than 10% of infants who die of SIDS had an ALTE prior to their death (SIDS by definition gives no warning).

• Periodic breathing: respiratory pattern in which three or more central apneas lasting 3 seconds in duration occur in a regularly repeating pattern within a 20-second period.
• Primary snoring: snoring whout associated apnea, hypoxemia, or hypoventilation.
• Central hypoventilation syndrome: decrease in central ventilatory drive leading to abnormal increase in carbon dioxide tension
• Obesity hypoventilation syndrome (Pickwickian syndrome): etiology is multifactorial; morbidly obese subjects who exhibit restrictive pulmonary disease, decreased central respiratory drive, with airway obstruction.
• Breath-holding spells

• Was the baby moving his or her chest with or without evidence of airflow?
• Was the motion paradoxical?
• Was the patient awake or asleep when the event occurred?
• Was there a color change (pale, cyanotic, red)?
• Was there a change in the patient’s muscle tone (floppy versus stiff)?
• Was the episode related to feeding or preceded by coughing, choking, gagging, vomiting, or crying?
• Was there a change in the patient’s mental status during or after the event?
• Was there any urinary or stool incontinence during the event?

• Evidence of infection (i.e., fever, rhinorrhea, nasal congestion, cough, diarrhea)?
• Gestational age (full-term or premature)
• Prior history of seizures or GER?
• Presence of snoring (snoring is never normal in a child)?
• Does the patient have headaches or daytime somnolence?
• Has there been a change in the patient’s school performance?

• Craniofacial abnormalities
  • Micrognathia
  • Macroglossia
  • Choanal atresia/stenosis
• Evidence of nasal obstruction
  • Congestion
  • Rhinorrhea
  • Foreign body
• Enlarged tonsils and adenoid tissue in toddlers/older children

• Heart rate
• Murmur
• Cyanosis

• Respiratory rate
• Chest mounts
• Quality of breath sounds

Finding: Was the child truly apneic?
Significance: Frequently, the parents see the child “not looking well” and assume the child is not breathing, rather than checking for respiratory effort.

Test: CBC with differential
Significance:

Test: Electrolytes
Significance: Bicarbonate, glucose

Test: Arterial blood gas
Significance: May be helpful in estimating significance of the event

Test: Polysomnography
Significance: Should be performed in any child with suspected obstructive or central sleep apnea

• O₂ saturation
• End-tidal CO₂ tension
• Respiratory movements (abdomen, chest)
• Airflow
• pH probe (if GER suspected)
• Record for minimum of 6 hours

Test: Chest radiography
Significance: Usually normal. Look for evidence of infection or aspiration.

Test: Lateral neck radiography
Significance:

Test: CT or MRI of head
Significance: Indicated if CNS pathology suspected as cause of central apnea

• NPO for 4 hours prior to pH probe study
• Make sure child does not take a nap prior to overnight study

• Caffeine
  • Loading dose: 10 mg/kg
  • Maintenance dose: 2.5 mg/kg/day
  • Therapeutic level: 5 to 20 mg/L
• Theophylline
  • Loading dose: 4 to 5 mg/kg
  • Maintenance dose: 3 to 5 mg/kg/d divided t.i.d.
  • Therapeutic level: 6 to 10 mg/L
• Supplemental O₂ is helpful for both obstructive and central apnea, especially if oxygen desaturation is occurring.

• Thickened feeds (1–3 teaspoons of rice cereal/oz of formula)
• Positioning (prone position for sleeping)
• Reglan (dose: 0.1 mg/kg/d given q.i.d.)
• Cisapride (dose: 0.3 mg/kg/d given q.i.d.)

• Continuous positive airway pressure (CPAP) to stint open the airways in obese patients with obstructive apnea.
• Bilevel positive airwary pressure (BiPAP) as mode of non-invasive ventilation is occasionally needed.

• Use is controversial.
• Monitoring technology now allows for the storing of information on a microchip, which can be downloaded for the physician to review.
• Indications
  • Any infant perceived to be at high risk for SIDS: severe ALTE (Note: no study has demonstrated efficiency of home monitoring therapy in preventing SIDS.)
  • One or more siblings who died of SIDS
  • Symptomatic premature infants
  • Central hypoventilation syndrome
  • Infants and young children who have tracheostomies

• Dependent on underlying cause of apnea
• Possible conflicts with other treatments
• GER may be exacerbated in patients requiring therapy with theophylline

• Dependent on underlying cause of apnea
• Premature infants usually outgrow apnea of prematurity by term to 4 weeks postgestational age.
• In obstructive apnea due to enlarged tonsils/adenoids, symptoms improve soon after surgery.

• In premature infants: excellent
• In children with enlarged tonsils/adenoids: excellent
• In obese patients: variable, due to difficulty in obtaining and maintaining weight loss

• Many false alarms with home monitors (stick-on electrodes have fewer false-positive alarms than electrodes attached to wraparound belts).
• Two-channel pneumography (heart rate and respirations) used to assess apnea in young infants can miss oxygen desaturation and obstructive apnea.

Q: When can monitoring be discontinued?
A: This is dependent on the underlying reason for monitoring. When the infant is no longer thought to be at increased risk of cardiorespiratory arrest or sudden death or when the infant has tolerated at least one respiratory infection without significant events, monitoring may be discontinued. Unfortunately, medicolegal issues also affect the decision to discontinue monitoring.

Q: Does monitoring prevent SIDS?
A: Monitoring can prevent death from other causes, but it has not been shown to decrease the incidence of SIDS.

Freed GE, Steinschneider A, Glassman M, et al. Sudden infant death syndrome prevention and an understanding of selected clinical issues. Pediatr Clin North Am 1994;41:967–990.

Keens TG, Davidson Ward SL. Apnea spells, sudden death, and the role of the apnea monitor. Pediatr Clin North Am 1993;40:897–911.

National Institute of Health Consensus Development Conference on Infantile Apnea and Home Monitoring. Pediatrics 1986;79:292–299.