Brief Resolved Unexplained Event

The electricity had gone off on that hot July day. The mother’s phone kept dinging with texts from the power company with an estimated fix time, which kept growing longer and longer. Meanwhile, the temperature in the house kept climbing, and the three small children grew more upset. After an hour, the mother decided it was time to go find air conditioning at her parents’ house. She laid the irritable, tiny baby in the playpen in the living room while she got the other two children ready to leave. The baby was four months old, but because he had been born at 28 weeks gestation, he was only the size of a newborn. His NICU stay had been unremarkable, and he’d come home before his due date, which, the mother realized suddenly, was today.

The two-year-old had to go to the potty, and the four-year-old wanted to gather his blanket and stuffed animals. Several minutes before they stood by the door, ready to go. The mother turned around to pick up the baby out of the playpen. He’d been silent, probably asleep, when the mother reached into the playpen. He felt… “wrong.” He was limp, his limbs dangling as she held him. The mother noticed all the things at once; his blue lips, closed eyes, the lack of rise and fall of his chest. She laid him on the floor and checked for a pulse. It was there, very faint, but there. She opened his airway and swept out some mucus, but the baby did not take a breath. In a panic, the mother called 911 and, in a justifiably hysterical tone, told the voice on the other end that the baby is not breathing.

This mother was me. (Just so you know, the baby is now a happy, healthy seven-year-old who wants to be a firefighter and farmer when he grows up!)

Let’s go back to that day for a moment. When he had come home from the NICU, they included a neonatal bag valve mask in the take-home bag for us, knowing that both his dad and I are paramedics. Luckily, on the day of the incident, it was in the living room, and while calling 911 on my cellphone’s speaker phone, I was able to start ventilations with the BVM. The volunteer fire department, which my husband was the assistant chief of, and I had been a member of for many years, was dispatched to an infant cardiac arrest and made the best response time they’d ever had. Fortunately, by the time they had arrived, my baby was breathing on his own again and responding normally.

After a hospital stay, my baby was diagnosed with a brief, resolved, unexplained event. This describes an event of apnea, color changing, cyanosis, and muscle tone change in an infant with no underlying explanation (Kondamudi, 2022). Formerly known as a near-miss sudden infant death syndrome event or apparent life-threatening event, the American Academy of Pediatrics changed the name to Brief Resolved Unexplained Event, or “BRUE,” in 2016. This diagnosis can only be made after an observed event, and all other etiologies are ruled out. Seizures, metabolic disorders, cardiac dysrhythmias, and respiratory infections can mimic a BRUE and must be ruled out before the diagnosis.

While any infant can have a BRUE, some infants are at a higher risk than others. Infants who were born at less than 32 weeks gestation, current postconceptional age of fewer than 45 weeks, and current age of fewer than 60 days are considered to be at higher risk than older infants and infants born at term (Ramgopal, 202022). BRUE accounts for less than 1% of all emergency room visits; one Italian study showed 4.1 cases in 1000 births (Monti, 2017). It is likely that emergency service providers will encounter a patient who has had a brief unresolved unexplained event during their career, whether it is treating the patient in the field or transferring the infant to a higher level of pediatric care. The infant will likely be asymptomatic when EMS professionals arrive on the scene, so it is important to do a thorough history and physical assessment. During the physical assessment, clinicians should remember that infant presentation can be misleading.

Assessment should begin with the Pediatric Assessment Triangle of noting appearance, work of breathing, and color, though it is likely that this will all be normal at the time of patient contact. Check the infant’s airway for any blockages, including mucus or vomit, and evaluate the rhythm and rate of breathing. Capillary refill and blood glucose should be checked, as well as a complete set of vital signs with SpO2, capnography, and cardiac rhythm. As with all assessments, any life-threatening findings should be immediately corrected or treated.

History taking should include the patient’s gestational age at birth, any medical diagnoses, recent fevers or vomiting, history of choking or gagging, and history of other unexplained life-threatening events, along with how the patient presented at the time of the BRUE. Ask about the length of the event and any skin color changes that the parent noted. As mentioned above, it is likely that the infant will be completely asymptomatic at the time of the assessment, but it is important to transport the patient for a full evaluation. Parents may believe that they overreacted or that the patient does not need evaluation at the Emergency Room, but EMS needs to assure parents that they did the correct thing by calling 911 and that the infant should be transported for a complete evaluation and to rule out any serious causes of this event.

While incredibly frightening events, almost all infants who have a BRUE will be discharged from the hospital and go on to have a healthy childhood. EMS providers should have a solid understanding of these events and perform a thorough assessment and history on the patient, despite the infant being asymptomatic at the time of encounter. Many things can appear to be a Brief, Resolved, Unexplained Event, such as a seizure, and paramedics should have a high index of suspicion for other explanations as well. All patients who present with a history of apnea, color changes, and altered mental status should always be transported to the emergency room for further evaluation.

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References

Kondamudi NP, Virji M. Brief Resolved Unexplained Event. [Updated 2022 Aug 14]. In:StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK441897/

Monti MC, Borrelli P, Nosetti L, Tajè S, Perotti M, Bonarrigo D, Stramba Badiale M, Montomoli C. Incidence of apparent life-threatening events and post-neonatal risk factors. Acta Paediatr. 2017 Feb;106(2):204-210. doi: 10.1111/apa.13391. Epub 2016 Apr 22. PMID: 26946490.

Ramgopal, S., Colgan, J.Y., Roland, D. et al. Brief resolved unexplained events: a new diagnosis, with implications for evaluation and management. Eur J Pediatr 181, 463–470 (2022). https://doi.org/10.1007/s00431-021-04234-5

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