Final answer:
The term for a newborn with a heart rate less than 100 bpm while breathing is 'bradycardia.' It is critical to monitor for symptoms indicating insufficient oxygenated blood to tissues and to treat based on the underlying cause of bradycardia.
Step-by-step explanation:
The term for a newborn that is breathing but has a heart rate less than 100 beats per minute (bradycardic) is 'bradycardia.' An adult's resting heart rate (HR) typically falls between 60-100 bpm, but for newborns, a HR below 100 bpm is considered bradycardia. While bradycardia in a newborn isn't always indicative of a serious condition, it's crucial to monitor for associated symptoms such as weakness, fatigue, dizziness, and cyanosis, which might suggest that the newborn's tissues are not receiving sufficient oxygenated blood. In such cases, immediate medical attention may be necessary to ensure the well-being of the newborn. Treatment would focus on identifying the underlying cause, whether it be related to the heart directly, such as an SA or AV node issue, or external factors such as metabolic or endocrine disorders.