Abbreviation: BRUE
BRUE was formerly known as Apparent life-threatening<unk>  (ALTE)
BRUE definition has a strict age limit (<1 y/o) and should only be considered if no other likely explanation
Peak incidence: 1 wk - 2 mo
BRUE is a symptom and requires evaluation for the actual diagnosis causing the<unk> 
Only 10% have repeat<unk> s
BRUE is not related to SIDS
BRUE diagnosis is only made by a clinician based on the features and is not based on the caregiver's perception of what happened. BRUE is an<unk>  occurring in an infant <1 year of age  when an observer reports a sudden,<unk>  ( <1 minute but typically <20–30 seconds), and now<unk>  episode of ≥1 of the following:
Cyanosis or pallor
Absent, decreased, or irregular breathing
Marked change in tone (hyper or hypotonia)
Altered level of responsiveness
Must have returned to baseline
A BRUE should only be diagnosed when there is no alternative explanation for a the<unk>  after completing full history and physical.
BRUE has a strict age limit < 1yo
There must be no other explanation for the<unk>  (not something as simple as nasal congestion, choking, viral infection or vomiting)
Caregiver's perception of a BRUE does not make an<unk>  a BRUE without clinical suspicion
Altered responsiveness is a new criteria
RSV infection
Prematurity
Recent anesthesia
GERD
Airway/maxillofacial anomalies
Age < 10 wks
History of apnea
Pallor, cyanosis, feeding difficulties
Family hx of sudden cardiac death
Brief resolved unexplained event
The differential diagnosis is extensive, and although a broad workup is often started in the ED including evaluation for sepsis, occult infection, and metabolic disorders, a cause is infrequently found[2]
Deterioration after intubation
Idiopathic 
Headache during pregnancy
GERD
Acute chest pain
Seizure