1. Apparent Life- Threatening Event K. Myra Lalas, MD 7/1

2. Definition Marked by a combination of the following features:  Apnea — usually no respiratory effort (central) or sometimes effort with difficulty (obstructive)  Color change — usually cyanotic or pallid but occasionally erythematous or plethoric  Marked change in muscle tone (usually limpness or rarely rigidity)  Choking or gagging Is a manifestation, not a diagnosis

3. Etiology  0.6 to 2.46 per 1,000 live births and representing 0.6% to 0.8% of all emergency visits for children younger than 1 year of age.  Average age of infants experiencing an ALTE is approximately 8 weeks.  Boys= girls Those at increased risk:  Premature infants  premature infants with RSV infections  premature infants who undergo general anesthesia  Infants who choke during feeding also are at increased risk

4. Diagnosis  HISTORY AND PHYSICAL EXAM  The most important diagnostic tool is a detailed description of the event and intervention obtained from the caretaker who witnessed the episode and any emergency personnel involved in the case.

5. Birth History, information about the pregnancy Infant's usual behavior, sleep and feeding habits Family history (including a history of siblings with ALTE, early deaths, genetic, metabolic, cardiac, and neurologic problems)

6. Social history (including the presence of smoking, alcohol or substance use in the home, and a list of medications in the home) Possibility of accidental or intentional administration of poisons or medications, including over-the-counter cold preparations

7. When the episode is assessed to be truly life-threatening and an explanation for the ALTE is not apparent based on the H & P, the initial laboratory evaluation may include:  CBC  Urinalysis  BMP, Mg  EKG  If the infant has a change in sensorium: consider toxicology screen

9. Differential Diagnosis Cardiovascular System  Anemia  Cardiomyopathy  Congenital heart disease  Dysrhythmia (prolonged QT syndrome, Wolff-Parkinson- White syndrome)  Myocarditis  Vascular rings and slings

10. Central Nervous System  Apnea of prematurity  Congenital brain malformation  Head trauma (child abuse)  Idiopathic central apnea  Increased intracranial pressure (congenital hydrocephalus, tumor)  Meningitis/encephalitis  Seizure Respiratory System  Breath-holding spell  Bronchiolitis (RSV)  Congenital malformation (choanal atresia, laryngeal cleft, tracheoesophageal fistula)  Foreign body  Laryngomalacia/tracheomalaci a  Laryngospasm (choking spell, gastroesophageal reflux)  Periodic breathing of infancy  Pertussis  Pneumonia  Smothering (intentional or unintentional)  Upper airway obstruction (nasal congestion)

11. Metabolic  Dehydration  Electrolyte abnormality (hyponatremia, hypocalcemia, congenital adrenal hyperplasia)  Hypoglycemia  Inborn errors of metabolism Systemic/ Others Hypothermia Sepsis Factitious (Munchausen's syndrome by proxy) Toxins/drugs

12. Home Monitors  Based on strong research evidence, home cardiorespiratory monitors should be used only for preterm infants or children who are either dependent on technology, have unstable airways, have medical conditions that involve disordered respiratory control, or have symptomatic chronic lung disease.

14. References Corwin Michael J, "Chapter 119. Apparent Life-Threatening Events and SIDS" (Chapter). Colin D. Rudolph, Abraham M. Rudolph, George E. Lister, Lewis R. First, Anne A. Gershon: Rudolph's Pediatrics, 22e. Fu, Linda and R. Moon. Apparent Life-threatening Events (ALTEs) and the Role of Home Monitors. Pediatr. Rev. 2007;28;203-208 Hall, K. Evaluation and Management of Apparent Life- Threatening Events in Children. Am Fam Physician. 2005 Jun 15;71(12):2301-2308. www.uptodate.com