Brief Resolved Unexplained Events in infants
Brief Resolved Unexplained Events (BRUEs) are a recent paediatric term used to describe a specific type of event in infants. The previous term, Acute Life-Threatening Event (ALTE), was replaced because it was broad and often led to unnecessary and costly investigations. The BRUE designation allows for a more precise, risk-stratified approach to management.
BRUE Criteria and Definition
A BRUE is a diagnosis of exclusion that can only be made after a thorough clinical assessment. An event in an infant younger than 12 months is classified as a BRUE if it is:
Brief: The event lasts less than 1 minute (typically under 20-30 seconds).
Resolved: The infant has returned to their baseline state of health.
Unexplained: A thorough history and physical examination reveal no identifiable medical cause.
The event itself must involve one or more of the following features:
Central cyanosis or pallor.
Absent, decreased, or irregular breathing.
Marked change in muscle tone (hypertonia or hypotonia).
Altered level of consciousness.
Assessment: History and Examination
The assessment is a detailed search for a possible cause, and a structured history is essential to determine if the event was a true BRUE.
History
Witness Account: Obtain a detailed, third-party account of the event. What exactly did the baby look like? What was their colour? What were they doing before and after the event?
Event Characteristics: Was the baby awake or asleep? What was their body position? Was it a single episode or part of a cluster?
Feeding History: A key area to explore is whether the event was related to a feed. Ask about feeding technique, volume, and any signs of reflux, choking, or aspiration.
Perinatal and Past Medical History: Review the birth history (prematurity is a key risk factor), and ask about any similar previous episodes.
Social History: Assess for any social factors that may suggest non-accidental injury (NAI).
Examination
Vital Signs: A full set of vital signs (heart rate, respiratory rate, oxygen saturation, and temperature) is essential.
Systemic Review: A thorough top-to-toe examination should be performed to look for any signs of an underlying condition (e.g., murmurs, abnormal neurological signs, signs of infection, or rash).
Head and Neck: Check for any signs of trauma, measure head circumference, and palpate the fontanelle.
Risk Stratification and Management
The key to managing a BRUE is risk stratification. The clinician must determine if the event was a low-risk or high-risk BRUE based on the child’s characteristics.
Low-Risk BRUE
An infant has a low-risk BRUE if they meet all of the following criteria:
Age > 60 days.
Gestational age at birth ≥ 32 weeks and post-conception age ≥ 45 weeks.
It was the first event.
The duration of the event was less than 1 minute.
There was no CPR required by a trained professional.
No concerning features on history or examination.
Management for Low-Risk BRUE:
No Investigation Required: The UK’s NICE guidelines and the American Academy of Pediatrics (AAP) recommend that these infants require no investigations.
Observation: They may be observed for a short period (1-4 hours) but can be discharged home after a clear discussion with the parents.
Safety Netting: Provide the parents with clear safety netting advice, including when to return to hospital and information on infant life support (ILSC) training.
High-Risk BRUE
An infant is considered high-risk if they do not meet all of the low-risk criteria. This includes infants who are younger than 60 days, have a history of prematurity, or have had a previous BRUE.
Management for High-Risk BRUE:
Admission: These infants should be admitted for a period of observation, which should include continuous cardiorespiratory and oxygen saturation monitoring.
Investigations: Investigations should be guided by a thorough clinical assessment. This may include:
Blood tests: Full blood count, electrolytes, glucose, and CRP.
Urine analysis: For a possible urinary tract infection (UTI).
ECG: To rule out a cardiac arrhythmia.
CXR: If a respiratory cause is suspected.
Referral: Discussion with a senior paediatrician is mandatory. In some cases, a subspecialty review (e.g., cardiology, neurology) may be necessary.