What is the appropriate evaluation and management for a Brief Resolved Unexplained Event (BRUE)?

Evaluation and Management of Brief Resolved Unexplained Events (BRUE)

Definition and Diagnostic Criteria

BRUE is a diagnosis of exclusion in infants <1 year old, characterized by a sudden, brief (<1 minute, typically 20-30 seconds), completely resolved episode of at least one of the following: cyanosis or pallor, absent/decreased/irregular breathing, marked tone change (hyper- or hypotonia), or altered responsiveness—with no identifiable cause after thorough history and physical examination. 1

Critical Exclusions That Preclude BRUE Diagnosis:

• Fever, respiratory symptoms, or nasal congestion 1
• Choking after vomiting or feeding (suggests gastroesophageal reflux) 1, 2
• Any explanation found on history or physical examination 1
• Events with rubor or redness (common in healthy infants) 1

Risk Stratification: Lower-Risk vs Higher-Risk

Lower-Risk BRUE Criteria (ALL must be met): 1

• Age >60 days
• Gestational age ≥32 weeks AND postconceptional age ≥45 weeks
• First event (no prior episodes)
• Event duration <1 minute
• No CPR required by trained medical provider
• Normal history and physical examination

Any infant not meeting ALL these criteria is classified as higher-risk and requires more extensive evaluation 1.

Essential History Components

Event Characterization: 1

• Exact duration (objective measurement if available)
• Witness reliability and number of observers
• Infant's state before event (awake/asleep, position, feeding status)
• Specific color change: cyanosis vs pallor (NOT rubor)
• Breathing pattern: absent, decreased, or irregular
• Tone changes: marked hypertonia or hypotonia
• Responsiveness: loss of consciousness, altered mental status, lethargy
• Interventions required to terminate event

Red Flags for Seizure Activity: 2

• Tonic eye deviation or nystagmus
• Tonic-clonic movements or infantile spasms
• Post-ictal phase (may be mistaken for event resolution)

Red Flags for Child Abuse: 1

• Multiple or changing versions of history
• History inconsistent with developmental stage
• Unexplained bruising, subconjunctival hemorrhage, bleeding from nose/mouth
• Rapid head enlargement or head circumference >95th percentile
• Previous child protective services involvement

Family History: 1, 2

• Sudden unexplained death in first- or second-degree relatives before age 35 (especially in infancy)
• Long QT syndrome or arrhythmias
• Prior BRUE/ALTE in siblings

Physical Examination Priorities

Mandatory Findings to Document: 1

• Anterior fontanel: size, fullness, bulging
• Scalp: bruising or bogginess
• Eyes: subconjunctival hemorrhage
• Oropharynx: frenula damage
• Skin: bruising or petechiae (especially trunk, face, ears)
• Neurologic: tone, responsiveness, developmental appropriateness
• Craniofacial abnormalities affecting airway

A normal physical examination does NOT rule out abusive head trauma. 1

Management of Lower-Risk BRUE

Testing NOT Recommended (Strong/Moderate Recommendations):

Do NOT obtain the following in lower-risk BRUE patients: 1

• Neuroimaging (CT, MRI, ultrasound) - Grade C, Moderate recommendation 1
• EEG - Grade C, Moderate recommendation 1
• White blood cell count, blood culture, or CSF analysis/culture - Grade B, Strong recommendation 1
• Chest radiograph - Grade B, Moderate recommendation 1
• Urinalysis - Grade C, Weak recommendation (may obtain if UTI suspected, but only culture if urinalysis positive) 1

Rationale for Minimal Testing:

The benefits of reducing unnecessary testing, radiation exposure, sedation, false-positive results, and caregiver anxiety outweigh the rare missed diagnostic opportunity, as serious underlying diagnoses occur in <5% of lower-risk BRUE cases 1, 3.

Optional Considerations for Lower-Risk BRUE:

• Brief observation period (duration not specified in guidelines) 3
• Electrocardiogram if family history of cardiac arrhythmia or Long QT syndrome 2
• Pertussis testing if exposure history or paroxysmal cough 1

Social Assessment Required: 1

Obtain assessment of social risk factors including:

• Negative attributions to child or unrealistic expectations
• Mental health problems, domestic violence
• Social service or law enforcement involvement
• Substance abuse
• Connect families with support resources

Management of Higher-Risk BRUE

Higher-risk patients require individualized evaluation based on specific risk factors identified. 1

When to Obtain Neuroimaging: 1

Brain imaging is indicated when abnormal history or physical examination raises concern for:

• Abusive head trauma (bruising, subconjunctival hemorrhage, bleeding, large/bulging fontanel, scalp findings)
• Structural brain abnormalities
• Intracranial pathology

Admission Considerations:

Most lower-risk BRUE patients do NOT require admission 3. Higher-risk patients may benefit from hospitalization for monitoring and evaluation based on specific concerning features 4.

Critical Pitfalls to Avoid

• Do NOT diagnose BRUE if vomiting or feeding-related choking occurred (suggests GER, not BRUE) 1, 2
• Do NOT be falsely reassured by normal imaging when clinical history suggests foreign body aspiration 2
• Do NOT perform blind finger sweeps 2
• Do NOT classify events with fever or respiratory symptoms as BRUE 1
• Do NOT rely solely on caregiver's perception that event was "life-threatening" - use objective clinical characterization 1
• Do NOT assume normal physical examination rules out child abuse 1

Follow-Up

Ensure timely outpatient follow-up with primary care provider for surveillance and caregiver education, including basic life support training 1. Consider subspecialty referral (neurology, cardiology, gastroenterology) based on specific concerning features identified during evaluation 1.

Note: Recent data (2022) suggest infants >60 days may actually be MORE likely to have serious underlying diagnoses (OR 1.43), contrasting with AAP criteria 4, highlighting the need for clinical judgment even in "lower-risk" patients.