What is a common characteristic of a BRUE?

A BRUE, or Brief Resolved Unexplained Event, is characterized by an episode that typically involves a sudden change in behavior or responsiveness in an infant, which may include apnea. Apnea is a cessation of breathing for more than 20 seconds and can be a central or obstructive form. This is significant because it reflects one of the primary concerns during an episode for infants, given that they can have prolonged episodes of not breathing that result in decreased oxygen levels.

The importance of recognizing apnea in this context is that it can be alarming and requires assessment to determine the cause and ensure the safety of the infant. Other options listed involve symptoms that are more indicative of different medical conditions rather than the characteristic nature of a BRUE, making them less relevant in this specific context.