Get CMEBrief Resolved Unexplained EventsWe have previously explored some issues with one of my “favorite” topics: Apparent Life Threatening Events (See ALTE and Never Trust a Neonate).  Recently, it has been recommended that the term “Apparent Life Threatening Event / ALTE” be removed from our medical lexicons.  Since we like to always stay in style and remain “hip and with it” (said in the voice of Dr. Evil), let’s review what the cool kids will be referring to in the future: Brief Resolved Unexplained Event / BRUE.


BRUE: What’s in a name?

  • We have known that the definition of an ALTE is imprecise at best.
    • This leads to challenges in studying the entity as a whole.
    • This also leads to many challenges with its evaluation and management.
    • “Life Threatening” also seems to generate confusion when the family is then told “everything is ok.”
  • Brief Resolved Unexplained Events” is the term now recommended to be used.
    • It aims to be more precise (at least it has age limits).
    • It highlights the reassuring qualities of the “typical” episode: Brief and Resolved.
    • The clinical practice guideline also defines “Lower Risk” patients.


BRUE: What is it?

  • BRUE describes an event that:
    • Occurs in a child younger than 1 year of age,
    • Lasts less than 1 minute (typically 20-30 seconds),
    • Has one or more of the following:
      • Central Cyanosis or Pallor 
        • Discoloration of face, gums and/or trunk.
        • Not acrocyanosis or only peri-oral cyanosis
        • Not rubor / redness
      • Absent, Decreased, or Irregular breathing
      • Marked change in tone (hypertonia or hypotonia)
      • Altered level of responsiveness
    • Resolves and patient returns to baseline, and
    • Has a reassuring history, physical exam, and vital signs during ED evaluation.
  • BRUE is used only when another condition cannot be discerned as the etiology of the event.
    • BRUE is still a constellation of symptoms that, in the end, may be attributed to a more specific diagnosis, but if you can be more specific at the outset, then do not label as BRUE.
      • For example, if a child has bronchiolitis and had an apneic event, that is not a BRUE… it is apnea associated with bronchiolitis.
      • Additionally, if the child a choking event, this is not a BRUE either. Maybe it is a T-E fistula…
    • A good goal is to attempt to use the H+P to determine a more precise Ddx rather than BRUE.


BRUE: Low Risk?

  • There are characteristics of patients at Lower Risk for having a serious underlying condition.
  • Lower Risk criteria:
    • Older than 60 days
    • Gestational Age 32 weeks or greater and a Postconceptional Age of 45 weeks or greater.
    • First BRUE (no previous BRUE ever and not occurring in clusters)
    • Not requiring CPR by a trained medical provider
    • NO concerning historic features 
      • See Guideline’s Table 2 for long list of features to consider [Tieder, 2016]
      • Some features not to overlook:
        • History concerning for potential Abuse.
        • Family history of sudden death in first degree relatives.
        • Social and Environmental issues
          • House mold problems (yes… mold is listed as a concerning feature)
          • Previous Child Protective Services or Law Enforcement involvement
          • Current level of concern/anxiety of family
    • NO concerning physical examination findings
      • Obviously, these children need a thorough physical exam… use your super sleuth skills.
      • Don’t overlook skin and genital exam.
  • If the patient does not meet Lower Risk criteria, then she/he is High Risk by default!


BRUE: What to do?

  • This is similar to what we would have done for ALTE.
  • There is a nice diagram in the Guideline’s… [Tieder, 2016]
  • But I’m simple so…
  • Medical Stabilization! 
    • Don’t forget, little neonates can be tricky and deceptive. Check capillary refill!
    • Check a glucose early! (I say this mostly so I don’t forget!)
  • History and Physical
    • The foundation upon which we build all medical decisions
    • Abnormal vital signs? H+P consistent with a specific diagnosis? – NOT a BRUE.
    • H+P meets BRUE criteria? No other explanation? – It’s a BRUE! (yeah)
      • Even if BRUE, consider the broad Ddx that exists
      • Try to narrow down the most likely culprits to help guide evaluation and work-up.
        • Cardiac vs Pulmonary
        • Neuro vs GI
        • Zebras vs Horses
  • Risk Stratify BRUE
    • This is simple… does the patient fit Lower Risk criteria?
      • Yes! = Lower Risk
      • No! = High Risk
    • Realize that Lower Risk does not equate to “No Risk.”
  • Disposition
    • High Risk
      • Hospitalize.
      • Base initial evaluation upon your assessment of most likely culprits on DDx.
        • Neonate doing weird things? –> LP and start antibiotics
        • “Funny” story that changes? –> Head CT and evaluate for NAT
      • We know that indiscriminate, broad work-ups are not useful.
    • Lower Risk
      • Avoid:
        • Indiscriminate labs and imaging studies – not helpful in this group either.
        • Empirically prescription of GI meds (ex, acid suppression medications) -unless you are diagnosing the episode was GER… in which case it is not a BRUE.
        • Admission solely for CardioPulmonary monitoring.
      • Do:
        • It is reasonable to obtain 12 Lead ECG.
        • Some advocate for pertussis testing.
        • Monitor the child in the ED and perform serial exams [Tieder, 2016]
          • 1-4 hours seems “reasonable” – no solid evidence
          • Establish stability of vital signs and exam.
          • May witness another event that assists in the diagnosis.
        • Educate family
          • Discuss BRUE.
          • Discuss CPR training for families.
          • Engage in shared decision making.
        • If, and only if, the stars align and the child can be discharged safely and the family is comfortable, ensure ability to be re-evaluated within the next 12-24 hours.


BRUE: What’s new?

Admittedly, this is my humble opinion (feel free to gently disagree with me… my feelings are fragile).

  • Essentially, I do not see this change in terminology as a huge alteration in my current practice.
    • I like the term BRUE as it accentuates the Brief and Resolved nature, but fear that that may also diminish provider’s vigilance.
    • “BRUE” should not equate to no concern, even though it does offer a pathway to actually discharge some.
    • Remember, being vigilant most often only requires a thorough H+P.
  • First and foremost: NEVER TRUST A NEONATE!
    • Similar to what we worried about with ALTE, BRUE in a neonate is concerning for badness!
    • Neonates are, by definition, High Risk kids in BRUE criteria.
  • Use your super sleuth skills for the history and exam – Is this a BRUE or something else that is Brewing (get it?).
  • Don’t order a million tests. Direct initial evaluation toward what your super sleuth skills have determined to be the most likely etiology of the event.
  • What’s new is the fact that there is now a guideline that supports the potential discharge of a LOWER RISK patient who has had a BRUE.
    • This does not mean all lower risk kids get to go home.
    • Part of the lower risk characteristics is the family’s perspective of the event.  It may be counterproductive to argue with a family that their CPR was not necessary and the kid is safe at home. (Yes, CPR provided by untrained personnel (ex, family) would still qualify as being Lower Risk potentially).
    • Often, the story and exam evolves… many times before your eyes… use observation in the ED in cases where you are unsure.


FOR ANOTHER PERSPECTIVE, See Dr. May’s post on St. Emlyns.



Tieder JS, Bonkowsky JL, Etzel RA, Franklin WH, Gremse DA, Herman B, Katz ES, Krilov LR, Merritt JL 2nd, Norlin C, Percelay J, Sapién RE, Shiffman RN, Smith MB; SUBCOMMITTEE ON APPARENT LIFE THREATENING EVENTS. Brief Resolved Unexplained Events (Formerly Apparent Life-Threatening Events) and Evaluation of Lower-Risk Infants. Pediatrics. 2016 May;137(5). PMID: 27244835. [PubMed] [Read by QxMD]

Tieder JS, Bonkowsky JL, Etzel RA, Franklin WH, Gremse DA, Herman B, Katz ES, Krilov LR, Merritt JL 2nd, Norlin C, Percelay J, Sapién RE, Shiffman RN, Smith MB; SUBCOMMITTEE ON APPARENT LIFE THREATENING EVENTS. Brief Resolved Unexplained Events (Formerly Apparent Life-Threatening Events) and Evaluation of Lower-Risk Infants: Executive Summary. Pediatrics. 2016 May;137(5). PMID: 27244836. [PubMed] [Read by QxMD]


Sean M. Fox
Sean M. Fox
Articles: 583


  1. When explaining BRUE (or ALTE for that matter) to a family in person or in their discharge instructions, how do we explain “event”? Some caregivers may not grasp the meaning of the word in this context. I medically edit patient education articles and instructions and need to be mindful of health literacy. Any ideas welcome.

  2. hi mr sean i find out that your topic is so interesting keep it up sir you’re helping a lot of people .. hope this will go broad so that other people will be aware of “BRUE” in fact my daughter she is 9months old had suffer this kind of situation and its so heartbreaking to me as a parent seeing your princess in pain after the first event the temperature of my daughter rise to 38.5 ‘C and followed up by 2nd event then 3rd in one day with a time interval of 2-3 hours. what should I do mr sean? im so puzzled right please help me.

    • I’m sorry to hear your daughter isn’t doing well!

      I, naturally, cannot give out personal medical advice via this venue, but it would be reasonable to bring your child to her medical provider to be evaluated in person.

      I wish you all of the best,

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