Diagnostic Certainty and Setting
Infantile colic is a diagnosis that is made retrospectively in the setting of an otherwise healthy infant who is growing and developing appropriately, and whose excessive crying ultimately resolves without medical intervention. Since colic is difficult to diagnose from any single medical encounter in the ED, it must be a diagnosis reached after excluding other possible causes.
Soothing the Colicky Infant
Extensive parental reassurance is required prior to discharging a colicky infant home—with the understanding that by the time of presentation in the ED, most parents have already exhausted their parental soothing abilities and personal coping mechanisms. Moreover, the typical physician’s promise that “this too, shall pass” is just not a sufficient addition to the parental armamentarium to manage their baby’s colic. Parents instead must be given effective techniques to calm colicky infants. Karp enumerates the following alliterative “5 Ss” guideline for soothing and calming fussy infants:
(1) Swaddling;
(2) Side/Stomach position (not while sleeping);
(3)“Shhhhhing” to provide a soothing sound that recalls the womb;
(4) Swinging the baby rhythmically in parents’ arms; and
(5) Sucking, either a pacifier or the mother’s breast.1
Equally important guidance prior to discharge from the ED is to inform parents that if they become overwhelmed by the baby’s fussing, it is always better to place an infant in the crib and let him or her cry alone for some time rather than allowing frustration to build with the baby in one's arms and increasing the potential of unintentionally harming the infant.
The “Don’t Miss” Differential Diagnoses
Whereas, as much as 43% of the infant population may experience excessive crying, only approximately 5% of infants with colic have underlying organic disease.8 The emergency physician (EP) is responsible for identifying this 5% when these infants present to the ED. A useful way to focus the initial evaluation of excessive crying is to determine the chronicity of the infant’s symptoms. To begin with, it is important to identify those babies who are in the ED merely because they have finally overwhelmed their parents with recurrent, intermittent bouts of prolonged crying despite being otherwise healthy and maintaining eating and sleeping patterns largely unaffected by crying. These are the infants who, after a thorough physical examination revealing none of the causes described below, should be swaddled, “shhhhhh’ed,” swung, suckled, and discharged with parental reassurance.
The EP, however, must be able to differentiate the classically colicky infant described above from the baby who has acutely developed unexplained crying and is at higher risk of serious disease or condition. In a study of afebrile infants experiencing an acute episode of excessive, prolonged crying, approximately 60% had an underlying disease process requiring management.9 Fortunately, many of these diagnoses can be made by an astute physical examination. In addition to evaluating infants for the most typical causes of new, prolonged crying, such as otitis media and anal fissures, the following common diagnoses should be clinically excluded in all infants presenting to the ED with acute, unexplained crying.
Corneal Abrasion
Performing a comprehensive eye examination on an inconsolable infant is not an easy task. However, corneal abrasions and foreign bodies in the eye are notorious causes of acute, excessive crying in infants—ones that are not always accompanied by conspicuous signs such as lacrimation or conjunctival injection.10
Fluorescein staining of both corneas should be performed to evaluate for a corneal abrasion. The infant’s eyelids should also be everted to look for retained foreign bodies, especially when vertical corneal abrasions have been visualized with fluorescein staining. Administering a topical ophthalmic anesthetic prior to fluorescein staining is advisable; this can be both therapeutic and diagnostic since resolution of crying after numbing the infant’s affected eye supports the diagnosis of corneal abrasion or foreign body.
Infants with corneal abrasions can be managed with a topical antibiotic ointment and 24-hour follow-up. Of note, recent studies indicate that asymptomatic corneal abrasions are extremely common in the infant period, suggesting that physicians should be careful to consider and exclude other potential causes of acute, excessive crying before attributing the symptoms to a corneal abrasion identified on examination.11
Hair Tourniquet Syndrome
Also referred to as hair thread tourniquet syndrome, the circumferential constriction of an infant’s appendage with hair, thread, or another fine material may present with the chief complaint of crying. Hair tourniquets most often involve the toes, followed by the fingers and external genitalia, and, if unrecognized or untreated, will lead to ischemia and necrosis of the distal tissue. Sleepwear that encloses the feet is a strong