Scope of the problem
Small children cry and cry and cry. In part, this is due to the limited repertoire of communication skills they possess. They cry because crying is remarkably effective; there is no other infant behavior that elicits an adult's attention and response more reliably than the cry. At 2 weeks of age, the average crying time of a normal infant is 2 hours per day. By age 6 weeks, that increases to nearly 3 hours per day. Fortunately, it decreases to about 1 hour per day by 12 weeks of age.
Inconsolable crying is a very challenging presentation for several reasons: the child (usually under 2 years of age) may have nonspecific symptoms (or no symptoms at all except for the crying), and the associated diseases can range from benign to life-threatening. Inconsolable crying is also very challenging for parents. The primary focus of the emergency practitioner should be to search for and rule out serious causes of crying and irritability. Benign etiologies, although more common, should be established only after first considering the serious etiologies.
Crying is one of the only ways by which an infant communicates discomfort or distress. In that sense, it is a nonspecific form of communication. However, the infant's cry is probably more than a distress signal. Studies of the acoustic qualities of infant cries indicate that the cry probably contains “encoded” messages about the state of early neurologic development.