Apparent Life-Threatening Events In Children

1. Definition
   1. Sudden, brief apnea and cyanosis in infant under age 1
2. Epidemiology
   1. Incidence: Up to 1 in 400 infants
   2. Occurs in infants under age 1, usually <10 weeks old
3. Risk Factors
   1. Male gender
   2. Feeding symptoms (rapid feeders, or feeding with cough)
   3. Premature Infants especially if accompanied by:
      1. Respiratory Syncytial Virus (RSV)
      2. General anesthesia history
4. Causes
   1. General
      1. ALTE after age 2 months predicts serious cause
      2. Idiopathic in 50% of cases
      3. No longer thought to be near-miss SIDS (older hypothesis)
   2. Gastrointestinal (50% of diagnosed cases)
      1. Pediatric Gastroesophageal Reflux
      2. Bowel disorder (Gastric volvulus, Intussusception)
   3. Neurologic (30% of diagnosed causes)
      1. Seizure Disorder (e.g. Febrile Seizures)
      2. Vasovagal reflex
      3. Structural (Budd-Chiari Syndrome, Hydrocephalus)
      4. CNS tumor or infection
   4. Respiratory (20% of diagnosed causes)
      1. Infection (RSV, Pertussis, Croup)
      2. Breath-Holding Spell
      3. Apnea of Prematurity
      4. Obstruction (Sleep Apnea, vocal cord, foreign body)
      5. Laryngotracheomalacia
   5. Cardiac (5% of diagnosed causes)
      1. Arrhythmia
      2. Congenital Heart Disease
   6. Metabolic (<5% of diagnosed causes)
      1. Inborn Errors of Metabolism
      2. Endocrine disorder
   7. Infection
      1. Urinary Tract Infection
      2. Sepsis
   8. Child Abuse (<5% of diagnosed causes)
      1. Smothering
      2. Munchausen by proxy
         1. Consider in repeat episodes seen by only 1 person
5. Symptoms
   1. Apnea
   2. Change in color (e.g. blue or cyanotic)
   3. Altered muscle tone (floppy or stiff)
   4. Coughing, Choking or gagging
6. History
   1. Event history
      1. Awake or asleep, prone or supine, and location?
      2. Occur with feeding, coughing, Choking, Vomiting?
      3. Respiratory effort? Skin Color? Muscle tone?
      4. Event duration?
      5. Interventions required (stimulation, CPR)?
   2. Recent illness
      1. Fever or rash
      2. Recent poor feeding or weight loss
      3. Irritable or Decreased Level of Consciousness
      4. Contagious contacts
   3. Medical history
      1. Prenatal and birth history
      2. Developmental Milestones met?
      3. Possible trauma
      4. Prior similar episodes
      5. Family History (SIDS, neurologic or cardiac disorder)
7. Diagnostic testing
   1. Individualize testing by history and exam
   2. High yield testing
      1. Complete Blood Count (CBC)
      2. Chemistry panel (Chem8)
         1. Serum electrolytes including calcium, Magnesium
         2. Serum bicarbonate
            1. Low level associated with more serious causes
            2. Consider checking serum lactate
      3. Urinalysis
      4. Chest XRay
      5. Pertussis nasal swab
      6. Respiratory Syncytial Virus (RSV) nasal swab
   3. Additional evaluation to consider
      1. Blood Culture
      2. Electrocardiogram
      3. MRI Brain
      4. Lumbar Puncture
      5. Liver Function Tests
8. Management
   1. Hospital observation and monitoring in most cases
   2. Consider home apnea monitor
   3. Treat specific cause if identified
   4. Consider empiric Pediatric GERD managemnt
9. Prognosis: Mortality risk
   1. Risk significantly increases with serious cause
      1. Central hypoventilation
      2. Seizure Disorders
      3. Cardiac arrhythmia
      4. Shannon (1992) Clin Perinatol 19:861-9
10. References
    1. Davies (2002) Emerg Med J 19:11-6
    2. Hall (2005) Am Fam Physician 71:2301-8