What is the recommended emergency department workup for an infant (<12 months) presenting with a brief resolved unexplained event (BRUE) in the pediatric emergency setting?

ED Workup for BRUE in Pediatrics

For lower-risk BRUE infants, minimal to no diagnostic testing is recommended—the workup is primarily a thorough history and physical examination, with selective testing only when specific concerns arise. 1

Risk Stratification is the Critical First Step

The 2016 AAP guideline fundamentally changed the approach to these events by introducing risk-based management. Your primary task is determining whether the infant meets lower-risk or higher-risk criteria 1.

Lower-Risk BRUE Criteria (ALL must be met):

• Age >60 days
• Gestational age ≥32 weeks AND postconceptional age ≥45 weeks
• First-ever event (no prior BRUE, not occurring in clusters)
• Event duration <1 minute
• No CPR by trained medical provider required
• No concerning historical features
• No concerning physical examination findings

1, 2

If even ONE criterion is not met, the infant is higher-risk and requires individualized evaluation beyond this guideline's scope.

History: What Actually Matters

Focus your history on these specific elements 2:

Event characteristics:

• Witness reliability and consistency of story
• Infant's state before event (awake/asleep, position, feeding)
• Specific symptoms during event: true cyanosis/pallor (NOT redness), absent or irregular breathing, marked tone changes (hyper/hypotonia), altered responsiveness
• How event resolved (spontaneously vs. intervention required)
• Exact duration (must be <1 minute for lower-risk)

Red flags for child abuse:

• Multiple or changing versions of history
• History inconsistent with developmental stage
• Unexplained bruising
• Negative caregiver attributions toward infant

Medical history exclusions:

• Fever, respiratory symptoms, nasal congestion = NOT a BRUE
• Choking after vomiting suggests GER = NOT a BRUE
• Any explanation for the event = NOT a BRUE

2

Physical Examination: The Diagnostic Foundation

A normal physical examination is REQUIRED for lower-risk classification 1. Examine systematically:

• Vital signs: Temperature, pulse, respiratory rate, BP, oxygen saturation
• General appearance: Age-appropriate responsiveness, craniofacial abnormalities
• Skin: Color, perfusion, bruising or injury
• Head: Fontanelles, signs of trauma
• Eyes: Extraocular movements, pupillary response, conjunctival hemorrhage
• Cardiovascular and respiratory: Murmurs, abnormal breath sounds
• Neurologic: Tone, reflexes, developmental appropriateness

2

Any abnormal findings automatically classify the infant as higher-risk.

Diagnostic Testing for Lower-Risk BRUE

The guideline explicitly recommends AGAINST routine testing 2:

What NOT to do:

• Do NOT obtain CBC, blood culture, CSF analysis/culture (Grade B, Strong Recommendation) 2

  • Serious bacterial infections in lower-risk BRUE are exceedingly rare
  • Infants with meningitis/sepsis have abnormal exams and don't meet lower-risk criteria

• Do NOT routinely obtain urinalysis (Grade C, Weak Recommendation) 2

  • If UTI concern exists, urinalysis can be obtained but only culture if UA is positive
  • Bag specimens are particularly prone to contamination

• Do NOT obtain chest radiograph (Grade B, Moderate Recommendation) 2

  • Pulmonary infections present with respiratory symptoms, excluding BRUE diagnosis

Selective Testing Considerations:

The guideline allows for selective testing based on specific historical or examination concerns, but emphasizes this should be the exception, not the rule. The framework prioritizes avoiding unnecessary testing, radiation exposure, pain, and false-positive results that lead to cascading interventions 2.

Common Pitfalls to Avoid

1. Over-testing due to caregiver anxiety: The frightening nature of these events often drives unnecessary workups. Education and reassurance are key 1.

2. Misclassifying age: An infant must be >60 days old. A 59-day-old is higher-risk by definition 2. Recent research suggests age may be over-weighted as a risk factor 3, but the current guideline stands.

3. Confusing redness with cyanosis: Rubor/redness is common in healthy infants and does NOT qualify as a BRUE 2.

4. Missing the "unexplained" requirement: If you identify ANY explanation (viral URI, GER, etc.), it's not a BRUE 2.

5. Applying lower-risk recommendations to higher-risk infants: The guideline provides NO recommendations for higher-risk patients—they require individualized evaluation 1, 4.

Management of Lower-Risk BRUE

While the question focuses on workup, management is minimal for truly lower-risk infants:

• Brief observation period (1-4 hours) may be reasonable
• Caregiver education about normal infant physiology
• CPR training for caregivers
• Close outpatient follow-up

Admission is generally not required for lower-risk BRUE 1, though recent data shows high admission rates persist (85-91%) 5, suggesting ongoing practice variation.

Higher-Risk BRUE

For infants not meeting all lower-risk criteria, a tiered evaluation approach prioritizes time-sensitive diagnoses 4:

Primary evaluation (time-sensitive):

• Child maltreatment assessment
• Cardiac arrhythmias (ECG, consider Holter)
• Serious infections
• Congenital abnormalities
• Metabolic disorders (consider if recurrent events) 6

Secondary evaluation (less time-sensitive):

• Dysphagia/feeding problems
• Airway obstruction
• Seizure disorders

This requires multidisciplinary coordination and often hospitalization 4.

The evidence strongly supports that well-appearing infants meeting all lower-risk criteria have excellent outcomes with minimal intervention 1, 3, making the thorough history and physical examination your most important diagnostic tools.