Chapter 7: Crying Infant

High-Yield Facts

• The infant cry may signal hunger, an unmet need for attention, a diaper change, or distress or pain.

• An infant not interacting with the parents appropriately or with a high pitched cry should be considered as having a serious medical condition until proven otherwise.

• It is important to observe the infant for at least 1 to 2 hours if one has not identified the cause. If after this period of observation, the crying abates, the infant may be sent home after close follow-up is established with the primary care physician. If the crying persists, the clinician should proceed with a more complete workup.

• Common pitfalls in assessing the crying infant include not undressing the infant, not examining the oropharynx, failing to consider abuse, and failing to establish close follow-up.

Overview

The assessment of the acutely crying infant in the emergency department (ED) is challenging and the clinician must resist the urge to rush through the history and physical examination. Instead, the clinician must be deliberate in the search for the cause, since the clues to the diagnosis may be subtle. The clinician should perform serial observations and examinations until the cause is found or the infant returns to normal behavior. Fortunately, with a thorough history, a meticulous physical examination, limited diagnostic tests, and a period of observation in the ED, most of the diagnoses of the crying, irritable infant are identified.¹

Normal Crying Patterns In Infancy and Colic

To unravel the cause of acute, unexplained crying, it is important to know what normal infant crying encompasses and the definition of colic. Crying is part of normal psychomotor and psychosocial development and is the infant's source of communication. The infant cry may signal hunger, an unmet need for attention, a diaper change, or distress or pain.

The normal crying pattern in the first year of life has been described.² There is a progressive increase in crying, which peaks in the second month of life and then gradually decreases.^2,3 The peak crying time may be as much as 2 to 3 hours per day at 6 weeks of life.⁴ The daily crying time decreases when the infant has other ways to communicate, such as interacting with a social smile. Infant crying time has been reported to usually decrease to 1 hour a day by 14 weeks of age (3.5 months).³

Colic is a chronic crying syndrome that occurs in the first 3 months of life. The etiology of colic is unknown. Colic typically begins at 3 weeks of age in an otherwise healthy infant. The infant with colic cries more than 3 hours per day, more than 3 days per week, and at least 3 weeks in duration (the rule of 3s).⁵ During a colic episode, infants flex their legs, their faces turn red, and ...